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Regulation of transcription | Biomolecules | MCAT | Khan Academy
 
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Created by Tracy Kim Kovach. Watch the next lesson: https://www.khanacademy.org/test-prep/mcat/biomolecules/gene-control/v/post-translational-regulation?utm_source=YT&utm_medium=Desc&utm_campaign=mcat Missed the previous lesson? https://www.khanacademy.org/test-prep/mcat/biomolecules/gene-control/v/dna-and-chromatin-regulation?utm_source=YT&utm_medium=Desc&utm_campaign=mcat MCAT on Khan Academy: Go ahead and practice some passage-based questions! About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s MCAT channel: https://www.youtube.com/channel/UCDkK5wqSuwDlJ3_nl3rgdiQ?sub_confirmation=1 Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
Views: 280264 khanacademymedicine
Gene Regulation
 
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031 - Gene Regulation Paul Andersen explains how genes are regulated in both prokaryotes and eukaryotes. He begins with a description of the lac and trp operon and how they are used by bacteria in both positive and negative response. He also explains the importance of transcription factors in eukaryotic gene expression. Do you speak another language? Help me translate my videos: http://www.bozemanscience.com/translations/ All of the images are licensed under creative commons and public domain licensing: Bioinformatik, English: Jawahar Swaminathan and MSD staff at the European Bioinformatics InstituteDeutsch: Jawahar Swaminathan und MSD Mitarbeiter am Europäischen Institut für BioinformatikPlattdüütsch: Jawahar Swaminathan un de Lüüd von MSD an dat Europääsche Institut för. English: Cartoon Representation of the Molecular Structure of Protein Registered with 2nvw Code., [object HTMLTableCellElement]. English: http://www.ebi.ac.uk/pdbe-srv/view/images/entry/2nvw600.png, displayed on http://www.ebi.ac.uk/pdbe-srv/view/entry/2nvw/summary. http://commons.wikimedia.org/wiki/File:PDB_2nvw_EBI.jpg. DNA, n.d. http://openclipart.org/detail/58543/dna-by-kumar35885. "File:E Coli at 10000x, Original.jpg." Wikipedia, the Free Encyclopedia, November 13, 2013. http://en.wikipedia.org/w/index.php?title=File:E_coli_at_10000x,_original.jpg&oldid=478393073. "File:Glass of Milk on Tablecloth.jpg." Wikipedia, the Free Encyclopedia. Accessed December 1, 2013. http://en.wikipedia.org/wiki/File:Glass_of_milk_on_tablecloth.jpg. "File:Lac operon1.png." Wikipedia, the Free Encyclopedia. Accessed December 1, 2013. http://en.wikipedia.org/wiki/File:Lac_operon1.png. "File:Protein TBP PDB 1c9b.png." Wikipedia, the Free Encyclopedia. Accessed December 1, 2013. http://en.wikipedia.org/wiki/File:Protein_TBP_PDB_1c9b.png. "File:Ribosome mRNA Translation En.svg." Wikipedia, the Free Encyclopedia. Accessed December 1, 2013. http://en.wikipedia.org/wiki/File:Ribosome_mRNA_translation_en.svg. Forluvoft. Simple Cartoon of Transcription Termination, October 9, 2007. Own work. http://commons.wikimedia.org/wiki/File:Simple_transcription_termination1.svg. Intro Music Atribution Title: I4dsong_loop_main.wav Artist: CosmicD Link to sound: http://www.freesound.org/people/CosmicD/sounds/72556/ Creative Commons Atribution License
Views: 1251533 Bozeman Science
Regulation of Gene Expression: Operons, Epigenetics, and Transcription Factors
 
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We learned about gene expression in biochemistry, which is comprised of transcription and translation, and referred to as the "central dogma" of molecular biology. But how is this process regulated? How does a cell know which genes to express and when? Well it's pretty complicated, but let's just get our feet wet by looking at operons, epigenetics, and transcription factors! To support this channel and keep up on STEM news at the same time, click on the link below and subscribe to this FREE newsletter: http://www.jdoqocy.com/click-9021241-13591026 Subscribe: http://bit.ly/ProfDaveSubscribe [email protected] http://patreon.com/ProfessorDaveExplains http://professordaveexplains.com http://facebook.com/ProfessorDaveExpl... http://twitter.com/DaveExplains Biology Tutorials: http://bit.ly/ProfDaveBio Biochemistry Tutorials: http://bit.ly/ProfDaveBiochem General Chemistry Tutorials: http://bit.ly/ProfDaveGenChem Organic Chemistry Tutorials: http://bit.ly/ProfDaveOrgChem Classical Physics Tutorials: http://bit.ly/ProfDavePhysics1 Modern Physics Tutorials: http://bit.ly/ProfDavePhysics2 Mathematics Tutorials: http://bit.ly/ProfDaveMaths American History Tutorials: http://bit.ly/ProfDaveAmericanHistory
Views: 163486 Professor Dave Explains
Up and down regulation. (Chapter 17)
 
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Explanation of up and down regulation in the endocrine system according to chapter 17 anatomy and physiology
Views: 28375 Withbothmyeyes
Gene Regulation and the Order of the Operon
 
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Explore gene expression with the Amoeba Sisters, including the fascinating Lac Operon found in bacteria! Learn how genes can be turned "on" and "off" and why this is essential for cellular function. Check out our FREE video handouts on http://www.amoebasisters.com/handouts! Support us on Patreon! http://www.patreon.com/amoebasisters Our FREE resources: GIFs: http://www.amoebasisters.com/gifs.html Handouts: http://www.amoebasisters.com/handouts.html Comics: http://www.amoebasisters.com/parameciumparlorcomics Connect with us! Website: http://www.AmoebaSisters.com Twitter: http://www.twitter.com/AmoebaSisters Facebook: http://www.facebook.com/AmoebaSisters Tumblr: http://www.amoebasisters.tumblr.com Pinterest: http://www.pinterest.com/AmoebaSister­s Instagram: https://www.instagram.com/amoebasistersofficial/ Visit our Redbubble store at http://www.amoebasisters.com/store.html The Amoeba Sisters videos demystify science with humor and relevance. The videos center on Pinky's certification and experience in teaching science at the high school level. Pinky's teacher certification is in grades 4-8 science and 8-12 composite science (encompassing biology, chemistry, and physics). Amoeba Sisters videos only cover concepts that Pinky is certified to teach, and they focus on her specialty: secondary life science. For more information about The Amoeba Sisters, visit: http://www.amoebasisters.com/about-us.html We cover the basics in biology concepts at the secondary level. If you are looking to discover more about biology and go into depth beyond these basics, our recommended reference is the FREE, peer reviewed, open source OpenStax biology textbook: https://openstax.org/details/books/biology We take pride in our AWESOME community, and we welcome feedback and discussion. However, please remember that this is an education channel. See YouTube's community guidelines https://www.youtube.com/yt/policyandsafety/communityguidelines.html and YouTube's policy center https://support.google.com/youtube/topic/2676378?hl=en&ref_topic=6151248. We also reserve the right to remove comments with vulgar language. Music is this video is listed free to use/no attribution required from the YouTube audio library https://www.youtube.com/audiolibrary/music?feature=blog We have YouTube's community contributed subtitles feature on to allow translations for different languages. YouTube automatically credits the different language contributors below (unless the contributor had opted out of being credited). We are thankful for those that contribute different languages. If you have a concern about community contributed contributions, please contact us.
Views: 671361 Amoeba Sisters
up regulation or down regulation of receptors to hormone availability in different situations
 
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General concepts of the Physiology-Receptor up/down regulation Hormone (1 st messenger ) → binds to receptor→ activation of some mediators (2 nd messenger ) → Physiologic response
Downregulation and upregulation
 
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Downregulation is the process by which a cell decreases the quantity of a cellular component, such as RNA or protein, in response to an external variable. An increase of a cellular component is called upregulation. An example of downregulation is the cellular decrease in the number of receptors to a molecule, such as a hormone or neurotransmitter, which reduces the cell's sensitivity to the molecule. This phenomenon is an example of a locally acting negative feedback mechanism. This video is targeted to blind users. Attribution: Article text available under CC-BY-SA Creative Commons image source in video
Views: 29171 Audiopedia
1672: Transcription Modulation or Receptor Down Regulation
 
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USMLE Step 1 Questions at http://www.latisom.com Life and Times in Schools of Medicine Inc. LATISOM offers a video streaming question bank for USMLE Step 1 and second year of medical school course work. Endocrinology questions
Views: 26 latisom
Communication 6- Receptor down- and up-regulation
 
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Part 6 in a 9 part lecture on CELLULAR COMMUNICATION in a flipped Human Physiology course taught by Wendy Riggs. CC-BY. Watch the whole lecture (all 9 videos) by going to the PLAYLIST: http://www.youtube.com/playlist?list=PL5GRRRmaGVqXs1wZIDZkAabn5yShU7iMb
Views: 16310 Wendy Riggs
How Intra-cellular Receptors Regulate Gene Transcription.
 
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Video is an animated explanation of How Intra-cellular Receptors Regulate Gene Transcription.
Views: 1287 EDGE
Gene Silencing by microRNAs
 
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MicroRNAs are a class of small, non-coding RNA molecules that regulate gene expression and have a big impact on many biological processes. This medical 3D animation shows the biogenesis and function of microRNAs within the cell. The goal of the project was to arouse interest by presenting the topic of gene silencing in a simplified and visually appealing way. It was part of my master`s graduation project where I had the opportunity to combine my two different studies Information Design and Molecular Biology. For schools and universities: If you want to embed the video on your site, please write my website http://www.katharinapetsche.com as a credit under the video. Thank you! Companies: If you want to use this video commercially, please get in contact: [email protected] CREDITS: Concept, Design, Animation: Katharina Petsche http://www.katharinapetsche.com Narrator: Steve Crilley Music: "Mutations" by Small Collin www.smallcolin.com
Views: 280382 Katharina Petsche
Mike Levine (UC Berkeley) Part 1: Transcriptional Precision: Enhancers
 
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https://www.ibiology.org/development-and-stem-cells/enhancers/ Levine discusses the important role of precisely regulating gene expression during animal development. The Drosophila embryo provides a model system because during early embryogenesis a syncytium with about 6000 synchronously dividing nuclei is formed before membranes are laid down to separate the nuclei and areas of regulated gene expression are created. These regions of specific gene expression ultimately determine the body plan of the organism. In Part 1 of his lecture, Levine emphasizes the importance of enhancers in regulating localized gene expression. Enhancers are elements located up or downstream from the transcription start site of a gene and they bind activators and repressors of gene expression. By integrating the effect of activators and repressors, enhancers produce sharp on/off boundaries of gene expression.
Views: 17321 iBiology
RNA interference (RNAi): by Nature Video
 
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RNA interference (RNAi) is an important process, used by many different organisms to regulate the activity of genes. This animation explains how RNAi works and introduces the two main players: small interfering RNAs (siRNAs) and microRNAs (miRNAs). We take you on an audio-visual journey, diving into a cell to show how genes are transcribed to make messenger RNA (mRNA) and how RNAi can silence specific mRNAs to stop them from making proteins. The animation is based on the latest research, to give you an up-to-date view. If you'd like to know more about the structures and processes you see in this video, check out the accompanying slideshow: http://www.nature.com/nrg/multimedia/rnai/animation/index.html Sponsor message (May 2014): Dharmacon RNAi products are now part of GE Healthcare. Learn more at http://www.GELifeSciences.com/Dharmacon
Views: 939364 nature video
Receptor Regulation, Pharmacology receptors desensitization and sensitization. Receptor upregulation
 
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Playlist of different topics on Pharmacology https://www.youtube.com/playlist?list=PLO7zfj2Ym5-YylSQ_ieOOSt5gXWKjPNAx receptor regulation pharmacology receptor regulation theory receptor regulation mechanism regulation receptor activity receptor regulation brain cell receptor regulation receptor down regulation receptor down regulation drug tolerance receptor density regulation receptor down regulation phosphorylation receptor dependent regulation receptor regulation in pharmacology receptor in regulation ligand receptor regulation receptor down regulation mechanism receptor regulation of receptor regulation physiology #IntroductiontoPharmacology, #GeneralPharmacology lectures Receptor Regulations, upregulation of receptor, down regulation of Receptor, receptor sensitisation receptor a desensitization, signal transduction, receptor regulation pharmacology mechanism of drug action, what is receptor, pharmacology of receptor, receptor pharmacology, receptor pharmacology in hindi. It is short video on Receptor regulation due to time limit. Various facts have not been included if this topic. However I tried my best to clearify fundamentals of receptor regulation Pharmacology. GPAT Discussion signal transduction, receptor regulation pharmacology Pharmacology Receptor. Receptor regulation is increase or decrease in number of Receptors. That is upregulation and down regulation. Addiction tolerance withdrawal syndrome or habit forming effect of drug is due to this receptor regulation. Solution pharmacy GPAT Discussion #NCLEXpharmacology NAPLX Pharmacology signal transduction,receptor regulation pharmacology
Views: 387 alok bains
Lac operon
 
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Overview of gene regulation in the Lac operon. Discussion of CAP, cAMP, lac repressor and allolactose in regulation of lac operon.
Views: 395037 Khan Academy
Gene structure: upstream-Downstream....Promoter..TATA box..!!!
 
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Basic of structural elements of a gene!!!!
Views: 12923 Kawshik Academy
DNA, Hot Pockets, & The Longest Word Ever: Crash Course Biology #11
 
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Hank imagines himself breaking into the Hot Pockets factory to steal their secret recipes and instruction manuals in order to help us understand how the processes known as DNA transcription and translation allow our cells to build proteins. Crash Course Biology is now available on DVD! http://dftba.com/product/1av/CrashCourse-Biology-The-Complete-Series-DVD-Set Like CrashCourse on Facebook! http://www.facebook.com/YouTubeCrashCourse Follow CrashCourse on Twitter! http://www.twitter.com/TheCrashCourse Table of Contents: 1) Transcription 2:12 A) Transcription Unit 3:00 B) Promoter 3:10 C) TATA Box 3:32 D) RNA Polymerase 4:12 E) mRNA 4:15 F) Termination signal 5:21 G) 5' Cap & Poly-A Tail 5:34 2) RNA Splicing 6:08 A) SNuRPs & Spliceosome 6:26 B) Exons & Introns 6:56 3) Translation 7:28 A) mRNA & tRNA 8:01 B) Triplet Codons & Anticodons 8:39 4) Folding & Protein Structure 10:51 A) Primary Structure 11:11 B) Secondary Structure 11:23 C) Tertiary Structure 11:58 D) Quaternary Structure 12:44 Links to episodes referenced in the video: DNA structure episode: http://www.youtube.com/watch?v=8kK2zwjRV0M Animal cells episode: http://www.youtube.com/watch?v=cj8dDTHGJBY Fold-it SciShow episode: http://www.youtube.com/watch?v=JdBcpdH_ptA REFERENCES for this video can be found in the Google document here: http://dft.ba/-2mxX This video contains the following sounds from Freesound.org: "IMPresora.wav" by melack "swishes.wav" by pogotron tags: crashcourse, science, biology, DNA, titin, hot pocket, transcription, translation, gene, RNA, enzyme, transcription unit, adenine, thymine, cytosine, guanine, TATA box, DNA strand, mRNA, messenger RNA, RNA polymerase, uracil, termination signal, RNA splicing, SNuRPs, spliceosome, exons, introns, ribosome, tRNA, transfer RNA, amino acid, nitrogenous base, codon, anticodon, polypeptide chain, folding, helix, pleated sheets, protein biosynthesis, gene expression Support CrashCourse on Subbable: http://subbable.com/crashcourse
Views: 3826327 CrashCourse
Transcription Termination in Prokaryotes
 
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Two classes of transcription terminators, Rho-dependent and Rho-independent, have been identified throughout prokaryotic genomes. These widely distributed sequences are responsible for triggering the end of transcription upon normal completion of gene or operon transcription, mediating early termination of transcripts as a means of regulation such as that observed in transcriptional attenuation, and to ensure the termination of runaway transcriptional complexes that manage to escape earlier terminators by chance, which prevents unnecessary energy expenditure for the cell. Rho-dependent terminators Rho-dependent transcription terminators require a protein called Rho factor, which exhibits RNA helicase activity, to disrupt the mRNA-DNA-RNA polymerase transcriptional complex. Rho-dependent terminators are found in bacteria and phage. The Rho-dependent terminator occurs downstream of translational stop codons and consists of an unstructured, cytosine-rich sequence on the mRNA known as a Rho utilization site (rut) for which a consensus sequence has not been identified, and a downstream transcription stop point (tsp). The rut serves as a mRNA loading site and as an activator for Rho; activation enables Rho to efficiently hydrolyze ATP and translocate down the mRNA while it maintains contact with the rut site. Rho is able to catch up with the RNA polymerase, which is stalled at the downstream tsp sites.[1] Contact between Rho and the RNA polymerase complex stimulates dissociation of the transcriptional complex through a mechanism involving allosteric effects of Rho on RNA polymerase. Rho Dependent Intrinsic transcription terminators or Rho-independent terminators require the formation of a self-annealing hairpin structure on the elongating transcript, which results in the disruption of the mRNA-DNA-RNA polymerase ternary complex. The terminator sequence in DNA contains a 20 basepair GC-rich region of dyad symmetry followed by a short poly-T tract or "T stretch" which is transcribed to form the terminating hairpin and a 7–9 nucleotide "U tract" respectively. The hairpin formation causes RNA polymerase stalling and destabilisation, leading to a greater likelihood that dissociation of the complex will occur at that location due to an increased time spent paused at that site and reduced stability of the complex.
Views: 913 Hussain Biology
Lac Operon
 
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NDSU Virtual Cell Animations Project animation 'Lac Operon'. For more information please see http://vcell.ndsu.edu/animations The Lac Operon is an example of an inducible system of gene expression. Its default state is to be inactive. Only when the right catalyst is added to the system, in this case the sugar lactose, is the process activated, allowing the genes in question to be expressed.
Views: 1388452 ndsuvirtualcell
How Intracellular Receptors Regulate Gene Transcription - medical animation
 
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MEDVIZZ - USMLE , PLAB , AMC , MCCQE , COMLEX , SLE , MRCP INSTITUTE FOR MEDICAL EDUCATION Live and online Training for all licensing Exams with Qbanks and study material .
Downregulation Meaning
 
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Video shows what downregulation means. The process, in the regulation of gene expression, in which the number, or activity of receptors decreases in order to decrease sensitivity. Downregulation Meaning. How to pronounce, definition audio dictionary. How to say downregulation. Powered by MaryTTS, Wiktionary
Views: 1391 ADictionary
Mod-04 Lec-13 Regulation of RNA Pol I transcription
 
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Eukaryotic Gene Expression:Basics & Benefits by Prof.P N RANGARAJAN,Department of Biochemistry,IISC Bangalore. For more details on NPTEL visit http://nptel.iitm.ac.in
Views: 1836 nptelhrd
Post-Transcriptional Modification of mRNA
 
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Biology Professor (Twitter: @DrWhitneyHolden) teaches about post-transcriptional modification of mRNA, including the addition of a 5' cap, a 3' poly-A tail, and splicing.
Views: 10615 Biology Professor
Operon
 
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PhET Simulation Gene Machine: The Lac Operon http://phet.colorado.edu/en/simulation/gene-machine-lac-operon In this video Paul Andersen describes the elements of an operon. The promoter allows the RNA polymerase to transcribe the required genes. The operator and repressor regulate the expression of the genes by blocking the RNA polymerase. The genes for a specific task are all located in sequence so that they can all be transcribed at once. He starts be describing how the lac operon can be initiated to break down lactose. He then explains how the trp operon can be activated to create tryptophan. He ends with a simulation of the lac operon. Intro Music Atribution Title: I4dsong_loop_main.wav Artist: CosmicD Link to sound: http://www.freesound.org/people/CosmicD/sounds/72556/ Creative Commons Atribution License All images are either Public Domain or Creative Commons Attribution Licenses: "File:André Lwoff Nobel.jpg." Wikipedia, the Free Encyclopedia. Accessed February 4, 2013. http://en.wikipedia.org/wiki/File:Andr%C3%A9_Lwoff_nobel.jpg. kumar35885. Simple DNA for Illustrations, n.d. http://openclipart.org/detail/58543/dna-by-kumar35885. "File:François Jacob Nobel.jpg." Wikipedia, the Free Encyclopedia. Accessed February 4, 2013. http://en.wikipedia.org/wiki/File:Fran%C3%A7ois_Jacob_nobel.jpg. "File:Jacques Monod Nobel.jpg." Wikipedia, the Free Encyclopedia. Accessed February 4, 2013. http://en.wikipedia.org/wiki/File:Jacques_Monod_nobel.jpg. "Gene Machine: The Lac Operon." PhET. Accessed February 4, 2013. http://phet.colorado.edu/en/simulation/gene-machine-lac-operon.
Views: 668874 Bozeman Science
Operons and gene regulation in bacteria
 
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Looking at how regulatory DNA sequences can repress or promote gene transcription (particularly in bacteria operons).
Views: 177714 Khan Academy
Epigenetics
 
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Hank & his clone Circus Hank explain the power of epigenetics, which studies the factors that determine how much or whether some genes are expressed in your body. Like SciShow on Facebook! http://www.facebook.com/scishow Follow SciShow on Twitter! http://www.twitter.com/scishow More SciShow! Solar Energy - http://youtu.be/4uPVZUTLAvA Foldit Gamers FTW - http://youtu.be/JdBcpdH_ptA
Views: 1941336 SciShow
Protein Synthesis (Updated)
 
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Explore the steps of transcription and translation in protein synthesis! This video explains several reasons why proteins are so important before explaining the roles of mRNA, rRNA, and tRNA in the steps of protein synthesis! Expand details for contents and resources. 👇Video handouts and resources on http://www.amoebasisters.com/handouts. This video replaces our old protein synthesis video: https://youtu.be/h5mJbP23Buo Table of Contents: 0:46 Why are proteins important? 1:48 Introduction to RNA 2:22 Steps of Protein Synthesis 2:43 Transcription 3:54 Translation 6:08 Introduction to mRNA Codon Chart 7:51 Quick Summary Image Vocabulary in this video includes DNA, mRNA, rRNA, and tRNA. This video mentions that proteins can be made of 1 or more polypeptide chains and that proteins typically experience folding and other modifications (to be functional proteins.) Codons and the amino acids they code for is represented by standard charts can be found in the public domain. While the rectangle chart is the common format, there may be other ways to represent the information. P.S. If learning about mutations, check out this cool codon chart that includes mutations(!!) in the public domain: https://commons.wikimedia.org/wiki/File:Notable_mutations.svg Our videos are designed to introduce basic concepts and hopefully to inspire students to stay curious about the content. We simply cannot include all of the exceptions and minute details in a video under 10 minutes, and this is why we so frequently remind people of this in our videos. We want students to go beyond our videos to explore the depth of the material. P.S. On our website, we emphasize that our videos contain science comics- not scientific illustrations. In real life, amoebas don't look like our characters. Our illustrated cell cartoons are definitely not to scale. Nitrogen and carbon don't tap dance. DNA is right-handed (but there are exceptions- worth a google) and doesn't have eyes...a face...or a top hat... Learn more about the purpose of our videos here: http://www.amoebasisters.com/our-videos.html Support us on Patreon! http://www.patreon.com/amoebasisters Our FREE resources: GIFs: http://www.amoebasisters.com/gifs.html Handouts: http://www.amoebasisters.com/handouts.html Comics: http://www.amoebasisters.com/parameciumparlorcomics Connect with us! Website: http://www.AmoebaSisters.com Twitter: http://www.twitter.com/AmoebaSisters Facebook: http://www.facebook.com/AmoebaSisters Tumblr: http://www.amoebasisters.tumblr.com Pinterest: http://www.pinterest.com/AmoebaSister­s Instagram: https://www.instagram.com/amoebasistersofficial/ Visit our Redbubble store at http://www.amoebasisters.com/store.html The Amoeba Sisters videos demystify science with humor and relevance. The videos center on Pinky's certification and experience in teaching science at the high school level. Pinky's teacher certification is in grades 4-8 science and 8-12 composite science (encompassing biology, chemistry, and physics). Amoeba Sisters videos only cover concepts that Pinky is certified to teach, and they focus on her specialty: secondary life science. For more information about The Amoeba Sisters, visit: http://www.amoebasisters.com/about-us.html We cover the basics in biology concepts at the secondary level. If you are looking to discover more about biology and go into depth beyond these basics, our recommended reference is the FREE, peer reviewed, open source OpenStax biology textbook: https://openstax.org/details/books/biology We take pride in our AWESOME community, and we welcome feedback and discussion. However, please remember that this is an education channel. See YouTube's community guidelines https://www.youtube.com/yt/policyandsafety/communityguidelines.html and YouTube's policy center https://support.google.com/youtube/topic/2676378?hl=en&ref_topic=6151248. We also reserve the right to remove comments with vulgar language. Music is this video is listed free to use/no attribution required from the YouTube audio library https://www.youtube.com/audiolibrary/music?feature=blog We have YouTube's community contributed subtitles feature on to allow translations for different languages, and we are thankful for those that contribute different languages! YouTube automatically credits the different language contributors below (unless the contributor had opted out of being credited). We are not affiliated with any of the translated subtitle credits that YouTube may place below. If you have a concern about community contributed contributions, please contact us.
Views: 1113300 Amoeba Sisters
Diallyl disulfide from garlic oil inhibits Pseudomonas aeruginosa virulence factors by inactivating
 
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Medicine by Alexandros G. Sfakianakis,Anapafseos 5 Agios Nikolaos 72100 Crete Greece,00302841026182,00306932607174,[email protected], https://plus.google.com/communities/115462130054650919641?sqinv=VFJWaER0c2NCRl9ERzRjZWhxQmhzY09kVV84cjRn , ,https://plus.google.com/u/0/+AlexandrosGSfakianakis , https://www.youtube.com/channel/UCQH21WX8Qn5YSTKrlJ3OrmQ , https://www.youtube.com/channel/UCTREJHxB6yt4Gaqs4-mLzDA , https://twitter.com/g_orl?lang=el, https://www.instagram.com/alexandrossfakianakis/, Diallyl disulfide from garlic oil inhibits Pseudomonas aeruginosa virulence factors by inactivating key quorum sensing genes via Latest Results for Applied Microbiology and Biotechnology Abstract Garlic oil can disrupt the quorum sensing (QS) pathways of the opportunistic pathogen Pseudomonas aeruginosa; however, the underlying mechanisms for this effect are unclear. Diallyl disulfide (DADS) is one of the most abundant sulfur-containing compounds in garlic oil. This study investigated the effects of DADS on the growth, virulence factor production (elastase, pyocyanin, biofilm, and swarming motility), and essential gene expression of P. aeruginosa PAO1, particularly as they apply to QS and virulence. DADS at 1.28 mg/mL did not affect P. aeruginosa PAO1 growth, although it decreased elastase and pyocyanin production, biofilm formation, and swarming motility. Each of these phenomena is regulated by the three QS systems of P. aeruginosa PAO1 (las, rhl, and pqs). Real-time q-PCR revealed that DADS down-regulated the transcription levels of several important QS genes (lasI, lasR, rhlI, rhlR, pqsA, and pqsR) in the three systems. Furthermore, the transcription levels of QS-regulated virulence genes were also down-regulated. The lasB gene, encoding LasB elastase, is co-regulated by the las, rhl, and pqs systems, and thus the down-regulation of genes across the three systems further down-regulated lasB. Additionally, phzM (encoding pyocyanin), pslB (responsible for the production of a biofilm matrix polysaccharide), and chiC (encoding chitinase) were positively activated by LasR, and a decrease in lasR transcription further down-regulated the transcription of phzM, pslB, and chiC. Hence, DADS inhibits P. aeruginosa PAO1 virulence factors by inactivating the transcription of key genes across three different QS systems. Add tags (Currently: Infectious Diseases, # Ola by Sfakianakis G. Alexandros)
Protein Synthesis
 
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Learn about the steps of protein synthesis in this video! I'll break down transcription, translation and the key players in the process of making protein.
Views: 1138069 Teacher's Pet
DNA Translation Made Easy
 
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Download Marrow Free : http://marrow.roundsapp.org/install Cells need translation to stay alive, and understanding how it works (so we can shut it down with antibiotics) can save us from bacterial infections. Let's take a closer look at how translation happens, from the first step to the final product. The genetic code In an mRNA, the instructions for building a polypeptide come in groups of three nucleotides called codons. Here are some key features of codons to keep in mind as we move forward: There are 616161 different codons for amino acids Three “stop” codons mark the polypeptide as finished One codon, AUG, is a “start” signal to kick off translation (it also specifies the amino acid methionine) These relationships between mRNA codons and amino acids are known as the genetic code (which you can explore further in the genetic code article). In translation, the codons of an mRNA are read in order (from the 5' end to the 3' end) by molecules called transfer RNAs, or tRNAs. Each tRNA has an anticodon, a set of three nucleotides that binds to a matching mRNA codon through base pairing. The other end of the tRNA carries the amino acid that's specified by the codon. Translation: Beginning, middle, and end A book or movie has three basic parts: a beginning, middle, and end. Translation has pretty much the same three parts, but they have fancier names: initiation, elongation, and termination. Initiation ("beginning"): in this stage, the ribosome gets together with the mRNA and the first tRNA so translation can begin. Elongation ("middle"): in this stage, amino acids are brought to the ribosome by tRNAs and linked together to form a chain. Termination ("end"): in the last stage, the finished polypeptide is released to go and do its job in the cell. Our polypeptide now has all its amino acids—does that mean it's ready to to its job in the cell? Not necessarily. Polypeptides often need some "edits." During and after translation, amino acids may be chemically altered or removed. The new polypeptide will also fold into a distinct 3D structure, and may join with other polypeptides to make a multi-part protein. Many proteins are good at folding on their own, but some need helpers ("chaperones") to keep them from sticking together incorrectly during the complex process of folding. Some proteins also contain special amino acid sequences that direct them to certain parts of the cell. These sequences, often found close to the N- or C-terminus, can be thought of as the protein’s “train ticket” to its final destination. For more about how this works, see the article on protein targeting.
Views: 83815 MEDSimplified
Regulation Of Lac Operon Animation
 
04:40
Regulation Of Lac Operon Animation - This video lecture explains about the regulation of lactose operon in animation format. Lac operon is explained in this animation video. Bacterial adapt to changes in their surroundings by using regulatory proteins to train groups of genes on and off in response to various environmental signals François Jacques are and Jack will now receive the Nobel Prize further experiments which increased our basic understanding of how the lactose metabolising genes are regulated in E. coli there are three structural protein coding genes involved in lactose metabolism in E. coli history -like genes are organised into the lack of and Ron is a cluster of genes along with an adjacent promoter and operator that control the transcription of those genes when the structural genes and in our piranha transcribed a single mRNA is produced mRNA is said to be partly systematic because it carries the information from more than one type of protein is a plus encoded by galactosidase which breaks down lactose into glucose and galactose plus encoded writers protease which transport lactose into the cell pass in current strands a sunrise function is not fully understood operator lack of class is a short region of DNA that lies partially within the promoter and relax with the regulatory proteins that controls the transcription of the operon the regulatory gene lack I pass produces an mRNA from which is synthesised repressor proteins that bind to the operator of the Mac operon the general term for the product of a regulatory gene is regulatory proteins regulatory proteins called a repressor because it keeps RNA polymerase from transcribing the structural genes in the absence of lactose -like repressor binds to the operator and RNA polymerase from transcribing the Mac genes when matters is present Manson are converted to an isomer called Alan lactose which acts as an inducement to turn on the lack of genes genes are expressed because Allah lactose binds to the lack repressor protein changing its shape so they cannot bind to the lack operator RNA polymerase can then bind to the promoter and transcribe the lack genes which are carbon nano produced mutations in the lack operon to show how they may affect the regulation of gene expression produced a mutation in the lack I gene lack minus such that in active repressor proteins are synthesised these proteins cannot bind to the operator result is that the structural genes are expressed constitutively that is in the presence or absence of lactose mutations in the operator can't constitute a lack OC DNA-based power to race and is in the operator region make this sequence and recognisable to the repressor protein. Repressor cannot bind the structural genes are always expressed in the absence or presence of lactose and a mutation in the lack I gene called black eye as super repressor showed no synthesis of the lack enzymes and the presence or absence of lactose this may repressor protein binds to the operator is unable to recognise Allah lactose therefore the lack repressor binds to the operator even in the presence of our lactose and transcription does not occur, Brian is one example of how bacteria can turn on or turn of genes in response to environmental conditions the presence of lactose induces the synthesis of enzymes necessary to convert lactose into glucose mutations in this operon demonstrate how the different regions of control. Thank You for watching our videos from Biology Animation Videos channel. This channel is created to compile animated biology lectures and videos from different animation sources. None of these videos are created by us. we just organize them and place them in YouTube for your understanding so If you want to know details about these animation please see the credit section for knowing the original content developer and please convey privilege and gratitude to them. Thank You. Title- Regulation of lac operon Our website- https://www.biologyanimationvideos.weebly.com Thank you for watching the lecture on lac operon regulation.
14.2.4 - trp Operon regulation, regulation of eukaryotic transcription
 
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Biology 122 Week14.Lecture2.Part4: trp Operon regulation, regulation of eukaryotic transcription
Views: 4796 dmflyboy
DNA replication and RNA transcription and translation | Khan Academy
 
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Watch the next lesson: https://www.khanacademy.org/science/biology/macromolecules/nucleic-acids/v/molecular-structure-of-dna?utm_source=YT&utm_medium=Desc&utm_campaign=biology Missed the previous lesson? https://www.khanacademy.org/science/biology/macromolecules/nucleic-acids/v/dna-deoxyribonucleic-acid?utm_source=YT&utm_medium=Desc&utm_campaign=biology Biology on Khan Academy: Life is beautiful! From atoms to cells, from genes to proteins, from populations to ecosystems, biology is the study of the fascinating and intricate systems that make life possible. Dive in to learn more about the many branches of biology and why they are exciting and important. Covers topics seen in a high school or first-year college biology course. About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy's Biology channel: https://www.youtube.com/channel/UC82qE46vcTn7lP4tK_RHhdg?sub_confirmation=1 Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
Views: 1839837 Khan Academy
Transcription elongation in prokaryotes | prokaryotic transcription lecture 3
 
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Transcription elongation in prokaryotes – This lecture explains about the prokaryotic transcription elongation. The elongation segment of transcription refers back to the system via which nucleotides are delivered to the developing RNA chain. As the RNA polymerase strikes down the DNA template strand, the open complicated bubble moves also. The bubble is of a constant quantity of nucleotides, meaning that at the main finish of the bubble the DNA helix is being unwound, while at its trailing end the single strands are being rejoined. Whereas separation of the DNA helix is everlasting in replication, it is just temporary in transcription. Depicts the opening steps in transcription up to elongation and the relative positions of the bubble and the polymerase holoenzyme. Because the figure indicates, within the open problematic bubble the DNA and RNA type a hybrid or joint tricky. The special size of this region is unknown, however it is notion to be between 3 and 12 base pairs lengthy and is located on the growing 3' end of the RNA. The figure also illustrates how the 5' tail finish of the RNA chain is separate from, versus base paired to, the DNA template strand. That is an additional difference between DNA replication and DNA transcription; in replication, the newly synthesized DNA strand remains bound in a helix to the strand with which it has base paired. After the preliminary stretch of roughly 8 base pairs has been synthesized, the sigma unit, which is dependable for awareness and binding to the promoter neighborhood, is released. The core enzyme is left to polymerize the developing RNA chain alone. This leads to the continuous extrusion of the 5' end of the RNA from the enzyme intricate. At ordinary room temperature, the price of transcription in prokaryotes is 40 nucleotides per second. For more information, log on to- http://www.shomusbiology.com/ Get Shomu's Biology DVD set here- http://www.shomusbiology.com/dvd-store/ Download the study materials here- http://shomusbiology.com/bio-materials.html Remember Shomu’s Biology is created to spread the knowledge of life science and biology by sharing all this free biology lectures video and animation presented by Suman Bhattacharjee in YouTube. All these tutorials are brought to you for free. Please subscribe to our channel so that we can grow together. You can check for any of the following services from Shomu’s Biology- Buy Shomu’s Biology lecture DVD set- www.shomusbiology.com/dvd-store Shomu’s Biology assignment services – www.shomusbiology.com/assignment -help Join Online coaching for CSIR NET exam – www.shomusbiology.com/net-coaching We are social. Find us on different sites here- Our Website – www.shomusbiology.com Facebook page- https://www.facebook.com/ShomusBiology/ Twitter - https://twitter.com/shomusbiology SlideShare- www.slideshare.net/shomusbiology Google plus- https://plus.google.com/113648584982732129198 LinkedIn - https://www.linkedin.com/in/suman-bhattacharjee-2a051661 Youtube- https://www.youtube.com/user/TheFunsuman Thank you for watching
Views: 117313 Shomu's Biology
Lac Operon
 
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Lac Operon A group of genes under the control of the same regulatory mechanism and are expressed at the same time. E. coli bacterium respires glucose but uses lactose if glucose is not available. An operon is a section of DNA that contains a regulatory gene that codes for an activator or repressor. A promoter is a DNA sequence located before the structural genes. An operator is another DNA sequence that allows a transcription factor to bind to the promoter and structural genes that code for functional proteins called enzymes. The regulatory gene codes for a protein known as a transcription factor. It can repress or activate the operator. When Lactose is not present The regulatory gene is called Lac 1. It is next to the promoter and operator respectfully. Attached to them are structural genes Lac Z, Lac Y and Lac A. Lac 1 causes the synthesis of a protein known as a transcription factor that can repress or activate the operator. Lac 1 is Lac repressor. It binds to the operator site and blocks RNA polymerase binding to the promoter. As a consequence no transcription will occur.no galactosidase, Lactose permease or transacetylase are produced. This is called Down regulation. When Lactose is present The regulatory gene Lac 1, promoter, operator and structural genes are present in the Lac Operon as before. Lac 1, the repressor transcription factor is still bind to the operator when glucose is present. But in the presence of Lactose, the lactose binds to the repressor and changes the shape of the Lac Repressor. As a result the repressor is released from the operator allowing the mRNA to bind to the promoter to start the process of transcription. Lactase permease, galactosidase and transacetylase are produced. Lactose is metabolised to produce glucose for the bacteria to respire. Research resources: OCR A A-Level Biology cgp books (2015) A Level Biology for OCR. Oxford University Press (2015)
Views: 55 Brian Caesar
Downregulate Meaning
 
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Video shows what downregulate means. To decrease the number of cell receptors by using downregulation. Downregulate Meaning. How to pronounce, definition audio dictionary. How to say downregulate. Powered by MaryTTS, Wiktionary
Views: 190 ADictionary
Gene expression
 
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In this video, the different ways that genes can be turned "on" or "off," "up" or "down" will be described. In addition, gene expression in operons will be described.
Views: 452 BiologyMonk
Gene Regulation - Introduction to Biology - 8.8
 
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Visit: http://academyofone.org AoO Prime: http://www.academyofone.org/register-2/ Royalty free music licensed by http://www.stockmusic.net Royalty free photos licensed by http://www.bigstockphoto.com Script: Genes are what make you you. They're what make me me. Genes are the thing that makes us human and genes are a great thing. There is, however, too much of a good thing in this world. And if your genes start to get out of hand then it will be a disaster for all of us. What’s going on everybody! My name is Jack Jenkins and this is Academy of One. Today we are talking about gene regulation. Gene regulation is very important and without it you will die. For example, without gene regulation you would create too much insulin. Insulin is a substance that is released from your cells. The purpose of insulin is to turn glucose into energy that you can use. Without gene regulation your cells will constantly release insulin into your bloodstream. With too much insulin, all the glucose in your blood will be taken and you will get something called hypoglycemia. Side effects of hypoglycemia are seizures, brain damage and death. This is why gene regulation is so important. Without gene regulation your body will produce way too much chemicals. Gene regulation is what is keeping you alive. The first thing you should know is that gene regulation is a huge topic and a lot of it is outside the scope of this course. Gene regulation will be covered at its extreme depth in a full length genetics course. For now the basics must subdue. Eukaryotes and prokaryotes regulate genes a little bit differently, in this video we will be covering prokaryotes more! Finally, it’s bacteria’s time to shine. All Prokaryotic DNA and some Eukaryotic DNA is organized in something called operons. An operon is a unit of functional DNA. An operon consist of four different parts. The first part of an operon is the promoter region. A promoter is a sequence of nucleotides that allows the gene to be transcribed. We already talked about the promoter region at nausea in video 8.5 and 8.6. Re Watch those videos for more information. The sort of second part is a regulator gene. A regulator gene is responsible for creating repressor proteins that slow down gene transcription. Repressor proteins is one of the response elements I talked about in the previous video. Now you may have noticed that I called the regulator gene a sort of second part of an operon. This is because it technically isn't part of the operon. It’s its own separate unit but for simplicity sakes scientist count it as part of an operon. The third part of an operon is the operator. The operator is the landing stage that physically contain the response elements. Let’s say the cell is under stress and we want to stop transcription. The regulator gene will create a repressor protein that will attach to the operator and stop the RNA polymerase from transcribing. The operator is usually between the promoter region and the gene but it can vary from cell to cell. The last part of an operon is a structural gene. A structural gene is a gene that codes for something that doesn't have to do with regulation. For instance, a lot of time the structural gene will code for a protein that will help with maintaining structure of the cell. In the end, all prokaryotes and most eukaryotes will use operons to stop or promote Transcription. This is how our genes are regulated. Well that’s it for this brief video about gene regulation. The next topic is an interesting one and is one I can’t wait to get into... Biotechnology. In the meantime, like, share and favorites this video. Visit Academyofone.org for more awesome videos, the full course, an awesome article and more. Follow us on twitter @academyofone. Lastly, have an amazing day everyone.
Views: 116 Academy of One
BIOLOGY GENE: EXPRESSION AND REGULATION NEET,AIIMS ,GATE ,GSCE ,BSC ,IIT JEE -MAINS,ADVANCED ,WBJEE
 
02:43
BIOLOGY GENE: EXPRESSION AND REGULATION NEET,AIIMS ,GATE ,GSCE ,BSC ,IIT JEE -MAINS,ADVANCED ,WBJEE VISIT OUR WEBSITE https://www.souravsirclasses.com/ FOR COMPLETE LECTURES / STUDY MATERIALS /NOTES /GUIDENCE / PAST YEAR SOLVED +SAMPLE PAPAERS /TRICKS /MCQ / SHORT CUT/ VIDEO LECTURES /LIVE + ONLINE CLASSES GIVE US A CALL / WHAST APP AT 9836793076 Also find us at…. BLOGSPOT http://souravdas3366.blogspot.com/ SLIDES ON COURSES https://www.slideshare.net/Souravdas31 TWITTER https://twitter.com/souravdas3366 FACEBOOK https://www.facebook.com/Sourav-Sirs-... LINKED IN https://www.linkedin.com/in/sourav-da... GOOGLE PLUS https://plus.google.com/+souravdassou... Regulation of gene expression includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products (protein or RNA), and is informally termed gene regulation. Sophisticated programs of gene expression are widely observed in biology, for example to trigger developmental pathways, respond to environmental stimuli, or adapt to new food sources. Virtually any step of gene expression can be modulated, from transcriptional initiation, to RNA processing, and to the post-translational modification of a protein. Often, one gene regulator controls another, and so on, in a gene regulatory network. Gene regulation is essential for viruses, prokaryotes and eukaryotes as it increases the versatility and adaptability of an organism by allowing the cell to express protein when needed. Although as early as 1951, Barbara McClintock showed interaction between two genetic loci, Activator (Ac) and Dissociator (Ds), in the color formation of maize seeds, the first discovery of a gene regulation system is widely considered to be the identification in 1961 of the lac operon, discovered by François Jacob and Jacques Monod, in which some enzymes involved in lactose metabolism are expressed by E. coli only in the presence of lactose and absence of glucose. In multicellular organisms, gene regulation drives cellular differentiation and morphogenesis in the embryo, leading to the creation of different cell types that possess different gene expression profiles from the same genome sequence. This explains how evolution actually works at a molecular level, and is central to the science of evolutionary developmental biology The initiating event leading to a change in gene expression includes activation or deactivation of receptors. Regulated stages of gene expression Any step of gene expression may be modulated, from the DNA-RNA transcription step to post-translational modification of a protein. The following is a list of stages where gene expression is regulated, the most extensively utilised point is Transcription Initiation: Chromatin domains Transcription Post-transcriptional modification RNA transport Translation mRNA degradation Modification of DNA In eukaryotes, the accessibility of large regions of DNA can depend on its chromatin structure, which can be altered as a result of histone modifications directed by DNA methylation, ncRNA, or DNA-binding protein. Hence these modifications may up or down regulate the expression of a gene. Some of these modifications that regulate gene expression are inheritable and are referred to as epigenetic regulation. Structural Transcription of DNA is dictated by its structure. In general, the density of its packing is indicative of the frequency of transcription. Octameric protein complexes called nucleosomes are responsible for the amount of supercoiling of DNA, and these complexes can be temporarily modified by processes such as phosphorylation or more permanently modified by processes such as methylation. Such modifications are considered to be responsible for more or less permanent changes in gene expression levels. Chemical Methylation of DNA is a common method of gene silencing. DNA is typically methylated by methyltransferase enzymes on cytosine nucleotides in a CpG dinucleotide sequence (also called "CpG islands" when densely clustered). Analysis of the pattern of methylation in a given region of DNA (which can be a promoter) can be achieved through a method called bisulfite mapping. Methylated cytosine residues are unchanged by the treatment, whereas unmethylated ones are changed to uracil. The differences are analyzed by DNA sequencing or by methods developed to quantify SNPs, such as Pyrosequencing (Biotage) or MassArray (Sequenom), measuring the relative amounts of C/T at the CG dinucleotide. Abnormal methylation patterns are thought to be involved in oncogenesis. Histone acetylation is also an important process in transcription. Histone acetyltransferase enzymes (HATs) such as CREB-binding protein also dissociate the DNA from the histone complex, allowing transcription to proceed. Often, DNA methylation and histone deacetylation work together in gene silencing. The combination of the two seems to be a signal for DNA to be packed more densely.
Chromatin remodelling and antisense-mediated up-regulation of the developmental switch gene
 
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Chromatin remodelling and antisense-mediated up-regulation of the developmental switch gene eud-1 control predatory feeding plasticity. Vahan Serobyan et al (2016). Nature Communications http://dx.doi.org/10.1038/ncomms12337 Phenotypic plasticity has been suggested to act through developmental switches, but little is known about associated molecular mechanisms. In the nematode Pristionchus pacificus, the sulfatase eud-1 was identified as part of a developmental switch controlling mouth-form plasticity governing a predatory versus bacteriovorous mouth-form decision. Here we show that mutations in the conserved histone-acetyltransferase Ppa-lsy-12 and the methyl-binding-protein Ppa-mbd-2 mimic the eud-1 phenotype, resulting in the absence of one mouth-form. Mutations in both genes cause histone modification defects and reduced eud-1 expression. Surprisingly, Ppa-lsy-12 mutants also result in the down-regulation of an antisense-eud-1 RNA. eud-1 and antisense-eud-1 are co-expressed and further experiments suggest that antisense-eud-1 acts through eud-1 itself. Indeed, overexpression of the antisense-eud-1 RNA increases the eud-1-sensitive mouth-form and extends eud-1 expression. In contrast, this effect is absent in eud-1 mutants indicating that antisense-eud-1 positively regulates eud-1. Thus, chromatin remodelling and antisense-mediated up-regulation of eud-1 control feeding plasticity in Pristionchus.
Views: 6760 ScienceVio
Transcription and mRNA processing | Biomolecules | MCAT | Khan Academy
 
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Introduction to transcription including the role of RNA polymerase, promoters, terminators, introns and exons. Watch the next lesson: https://www.khanacademy.org/test-prep/mcat/biomolecules/dna/v/speed-and-precision-of-dna-replication?utm_source=YT&utm_medium=Desc&utm_campaign=mcat Missed the previous lesson? https://www.khanacademy.org/test-prep/mcat/biomolecules/dna/v/leading-and-lagging-strands-in-dna-replication?utm_source=YT&utm_medium=Desc&utm_campaign=mcat MCAT on Khan Academy: Go ahead and practice some passage-based questions! About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s MCAT channel: https://www.youtube.com/channel/UCDkK5wqSuwDlJ3_nl3rgdiQ?sub_confirmation=1 Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
Views: 669252 Khan Academy
Gene Expression III - Kevin Ahern's BB 451 Lecture #50 2017
 
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Contact me at [email protected] Friend me on Facebook at kevin.g.ahern Highlights Gene Expression (continued) 1. Modifications to the chromatin can include acetylation/deacetylation, methylation/demethylation, phosphorylation/dephorphorylation, and ubiquitination. Chemical modification of histones changes their interactions with the DNA and consequently affect transcription of genes adjacent to the modifications. 2. Chemical modifications to histones can be transmitted from parent to offspring and result in changes in gene expression that are inherited without changing DNA sequences. This changes are known as epigenetic changes. 3. Calorie deprivation is a documented life extender in many organisms and proteins called sirtuins (see below) may play roles in that process. It is thought that organisms have built-in responses to calorie deprivatoin that result in changing body processes to facilitate survival long enough to reproduce. 4. A Swedish study known as the Överkalix study tracked families for over 100 years. During this time some members of the study experienced famine and the responses to it appear to have been transmitted across generations. The food supply of grandmothers had an effect on the mortaility risk of their granddaughters, but not their grandsons. Similarly, the food supply of grandfathers had an effect on the mortaility risk of their grandsons, but not their granddaughters. 5. Chemical changes to chromatin that "loosen" it and faciltate trasncription convert it into the form referred to as euchromatin. Changes that make chromatin more compact do not favor transcription and are created a form of chromatin known as heterochromatin. 6. Acetylation tends to favor loosening of chromatin whereas deacetylation of chromatin has the opposite effect. Histone deacetylases are known as HDACs and a good example is the family of proteins known as the sirtuins. 7. Sirtuins are down-regulated in insulin resistance and increased expression of them in some systems (mice, for example) appears to play a role in longevity. 8. In addition to histones, DNA bases can also be modified chemically and these effects appear to operate on the ability of proteins that recognize those sequences to bind to them. Cytosine is the base modified in eukaryotes and this can (but doesn't have to) occur in the sequence CpG. If this sequence is located close to a gene, it may prevent transcription of the gene and this chemical modification (and change in transcription) can be transmitted across generations (epigenetic). 9. Enhancer sequences are targets for transcriptional activators made in specific tissues to specifically activate (or in some cases inhibit) transcription of genes under their control in those specific tissues. 10. Transcriptional activators work by binding enhancers and with bending of the DNA, the activator can be brought into close proximity of a promoter sequence adjacent to a gene where it can help facilitate construction of the transcription complex. 11. Insulator sequences (also called silencers) are sequences that are much like enhancers, but operate instead to inhibit formation of the transcription complex. They can be bound by a protein called CTCF and its binding is inhibited by CpG methylation as well. 12. In eukaryotic cells, the ferritin mRNA has a region of it called an iron response element (IRE) that can be bound by a protein called IRE-BP (iron response element binding protein). IRE-BP binds the iron response element when iron is absent.When iron is absent, the IRE is not bound by the IRE-BP and translation proceeds because the ribosome is not blocked by the IRE-BP. 13. When iron is abundant, IRE-BP binds to iron and can't bind to the IRE. If IRP-BP is NOT bound to the iron response element (high iron conditions), ferritin is made because the IRP does not block the ribosome from translating the mRNA. Thus, when iron concentration is high, ferritin is synthesized to hold it. When IRP is bound to the iron response element (low iron conditions), ferritin is not made. Thus when iron is not available, ferritin is not made. Gene expression of ferritin is therefore a function of translational control. 14. The transferrin receptor has multiple iron response elements at the 3' end of its mRNA. When IRE-BP binds to it, the 3' end is protected and nucleases do not degrate the transferring mRNA and the transferrin receptor is made. Thus, when iron is low, the IRE-BP binds the mRNA, protecting it, and the transferrin receptor is made to bring iron into the cells. When iron is high, the IRE-BP bind iron and can't bind to the IRE in the the mRNA's 3' end, leaving it susceptible to degradation. Gene expression of the transferrin receptor is therefore a function of stability of the stability of that gene's mRNA.
Views: 701 Kevin Ahern
Gene Regulation II
 
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This course is part of a series taught by Kevin Ahern at Oregon State University on General Biochemistry. For more information about online courses go to http://ecampus.oregonstate.edu/ for the rest of the courses see http://www.youtube.com/playlist?list=PL347B70A1CC0D91C6 Also check out the free textbook "Biochemistry Free and Easy" at: http://biochem.science.oregonstate.edu 1. Negative transcriptional regulation of the lac operon is accomplished by a protein known as the lac repressor. It binds the operon's operator region and inhibits transcription. 2. In the absence of inducer molecules, the lac repressor tightly binds to the operator and inhibits transcription of the operon. When inducer molecules are present, they bind to the lac repressor and change its shape and reduce its ability to bind the operator, thus allowing the RNA polymerase to bind the promoter and start transcription. 3. CAP (also called CRP) must bind to cAMP in order to function. When CRP binds cAMP, its affinity increases for the lac operon adjacent to the RNA polymerase binding site (-68 to -55). This binding facilitates transcription of the lac operon by stimulating the binding of RNA polymerase to begin transcription. 4. When both CAP and the lac repressor are bound to the lac operon, the repressor 'wins', shutting down transcription of the operon. 5. In eukaryotic cells, DNA is wrapped up (coiled up) with basic proteins called histones. Histone sequences are strongly conserved from yeast to humans. 6. Four histones form a core around which DNA is wrapped. This core contains two copies each of histones H2A, H2B, H3, and H4. This core of proteins is called an octamer. 7. The appearance of chromatin DNA is that of beads on a string, with the octamer wrapped with DNA composing the beads and the DNA strand coated with histone H1 (and H5) composing the string. 8. Histones of the octamer have strong structural similarity to each other. 9. Wrapping of DNA around the histone octamer provides only partial compression of the length of a DNA molecule. Additional compression occurs as a result of coiling of octamer/DNA complexes as well, forming higher order structures. 10. Enhancer sequences are bound by enhancer proteins and are found only in eukaryotes. Multiple enhance sequences may be present before the start site of a particular gene. Binding of enhancer proteins to enhancer sequences allows for tissue specific expression of genes if the enhancer proteins themselves are expressed tissue specifically. Enhancer proteins help to "clear" out the histones from a region of a chromosome to allow transcription to occur. 11. Nuclear hormone receptors, such as the estrogen receptor, have DNA binding domains and ligand binding domains. The binding of the estradiol (and estrogen) ligand to the estrogen receptor causes a conformational change in the protein, but does not change the binding of the protein to DNA. Binding of the estradiol DOES appear to activate the protein and thus activate transcription of the genes that the receptor binds to the promoter of. 12. The key to action of the nuclear hormone receptor that binds estradiol is that binding of estradiol favors binding of the receptor to co-activator proteins. These co-activator proteins help to turn on transcription of the relevant genes. Binding of co-activator proteins by transcriptional factors, such as the estrogen receptor is called recruitment. 13. An antagonist of the estrogen receptor is the drug tamoxifen. Antagonists bind proteins and prevent them from acting. Binding of tamoxifen by the estrogen receptor stops the receptor from activating transcription of genes that it normally activates. 14. Tamoxifen appears to act by binding the estrogen receptor (I use the terms estrogen receptor and nuclear hormone receptor here as the same thing), with a part of the molecule extending into the region of the protein that normally binds to co-activators. Thus, tamoxifen acts by stopping recruitment by the receptor of co-activators. Tamoxifen is used to treat tumors that are stimulated by the binding of estrogens to the receptor. 15. Altering chromatin structure is an essential function for transcriptional activation in eukaryotes. Co-activator proteins appear to play a role in this process by catalyzing the acetylation of lysine residues in histones. Acetylation of histone lysines neutralizes their positive charge, changing the affinity of histones for DNA and changing the nature of their interaction with DNA, thus allowing more proteins to be able to gain access to the DNA where the acetylation has occurred. 16. Proteins involved in transcriptional control often have bromodomains. These regions of protein recognize and bind to acetylated lysine residues in histones.
Mutations: The Potential Power of a Small Change
 
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The Amoeba Sisters discuss gene and chromosome mutations and explore the significance of these changes. Music used with permission from Adrian Holovaty (http://www.youtube.com/adrianholovaty). This video has a handout here: http://www.amoebasisters.com/handouts.html We appreciate the feedback we get for clarification or improvements on our videos. At 2:11, we try make the A (adenine) base look upset now that the complementary base T (thymine) has been replaced with a G (guanine) in a point mutation. But we wish we had put more distance between the cartoon bases to clarify, that now, they cannot bond in this way. Note: This can sometimes be fixed by a polymerase in proofreading- but if not fixed- the G may be be matched with a C and the mutation will remain. You may enjoy our updated mutation GIF: https://twitter.com/AmoebaSisters/status/930472869343191041 Support us on Patreon! http://www.patreon.com/amoebasisters Our FREE resources: GIFs: http://www.amoebasisters.com/gifs.html Handouts: http://www.amoebasisters.com/handouts.html Comics: http://www.amoebasisters.com/parameciumparlorcomics Connect with us! Website: http://www.AmoebaSisters.com Twitter: http://www.twitter.com/AmoebaSisters Facebook: http://www.facebook.com/AmoebaSisters Tumblr: http://www.amoebasisters.tumblr.com Pinterest: http://www.pinterest.com/AmoebaSister­s Instagram: https://www.instagram.com/amoebasistersofficial/ Visit our Redbubble store at http://www.amoebasisters.com/store.html The Amoeba Sisters videos demystify science with humor and relevance. The videos center on Pinky's certification and experience in teaching science at the high school level. Pinky's teacher certification is in grades 4-8 science and 8-12 composite science (encompassing biology, chemistry, and physics). Amoeba Sisters videos only cover concepts that Pinky is certified to teach, and they focus on her specialty: secondary life science. For more information about The Amoeba Sisters, visit: http://www.amoebasisters.com/about-us.html We cover the basics in biology concepts at the secondary level. If you are looking to discover more about biology and go into depth beyond these basics, our recommended reference is the FREE, peer reviewed, open source OpenStax biology textbook: https://openstax.org/details/books/biology We take pride in our AWESOME community, and we welcome feedback and discussion. However, please remember that this is an education channel. See YouTube's community guidelines https://www.youtube.com/yt/policyandsafety/communityguidelines.html and YouTube's policy center https://support.google.com/youtube/topic/2676378?hl=en&ref_topic=6151248. We also reserve the right to remove comments with vulgar language. We have YouTube's community contributed subtitles feature on to allow translations for different languages. YouTube automatically credits the different language contributors below (unless the contributor had opted out of being credited). We are thankful for those that contribute different languages. If you have a concern about community contributed contributions, please contact us.
Views: 1071637 Amoeba Sisters
DNA Replication: The Cell's Extreme Team Sport
 
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Learn the steps of DNA replication, the enzymes involved, and what it means to be a leading or lagging strand! This video has a handout here: http://www.amoebasisters.com/handouts See table of contents by expanding details 👇 Table of Contents: Where and When DNA Replication Occurs 0:37 Why Do You Need to Make More DNA? 1:48 (Some of the) Enzymes Involved in DNA Replication 2:02 DNA Replication Steps 3:22 What does 5' to 3' or 3' to 5' mean? 4:43 Lagging Strand 6:04 Support us on Patreon! http://www.patreon.com/amoebasisters Our FREE resources: GIFs: http://www.amoebasisters.com/gifs.html Handouts: http://www.amoebasisters.com/handouts.html Comics: http://www.amoebasisters.com/parameciumparlorcomics Connect with us! Website: http://www.AmoebaSisters.com Twitter: http://www.twitter.com/AmoebaSisters Facebook: http://www.facebook.com/AmoebaSisters Tumblr: http://www.amoebasisters.tumblr.com Pinterest: http://www.pinterest.com/AmoebaSister­s Instagram: https://www.instagram.com/amoebasistersofficial/ Visit our Redbubble store at http://www.amoebasisters.com/store.html The Amoeba Sisters videos demystify science with humor and relevance. The videos center on Pinky's certification and experience in teaching science at the high school level. Pinky's teacher certification is in grades 4-8 science and 8-12 composite science (encompassing biology, chemistry, and physics). Amoeba Sisters videos only cover concepts that Pinky is certified to teach, and they focus on her specialty: secondary life science. For more information about The Amoeba Sisters, visit: http://www.amoebasisters.com/about-us.html We cover the basics in biology concepts at the secondary level. If you are looking to discover more about biology and go into depth beyond these basics, our recommended reference is the FREE, peer reviewed, open source OpenStax biology textbook: https://openstax.org/details/books/biology P.S. On our website, we emphasize that our videos contain science comics- not scientific illustrations. In real life, amoebas don't look like our characters. Our illustrated cell cartoons are definitely not to scale. Nitrogen and carbon don't tap dance. DNA is right-handed (but there are exceptions- worth a google) and doesn't have eyes...a face...or a top hat... Learn more about the purpose of our videos here: http://www.amoebasisters.com/our-videos.html We take pride in our AWESOME community, and we welcome feedback and discussion. However, please remember that this is an education channel. See YouTube's community guidelines https://www.youtube.com/yt/policyandsafety/communityguidelines.html and YouTube's policy center https://support.google.com/youtube/topic/2676378?hl=en&ref_topic=6151248. We also reserve the right to remove comments with vulgar language. Music is this video is listed free to use/no attribution required from the YouTube audio library https://www.youtube.com/audiolibrary/music?feature=blog We have YouTube's community contributed subtitles feature on to allow translations for different languages. YouTube automatically credits the different language contributors below (unless the contributor had opted out of being credited). We are thankful for those that contribute different languages. If you have a concern about community contributed contributions, please contact us.
Views: 3081423 Amoeba Sisters
Transcription II
 
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This course is part of a series taught by Kevin Ahern at Oregon State University on General Biochemistry. For more information about online courses go to http://ecampus.oregonstate.edu/ for the rest of the courses see http://www.youtube.com/playlist?list=PL347B70A1CC0D91C6 1. The factor involved in factor dependent transcription termination in E. coli is called rho. It binds to the 5' end of an RNA being made and (using ATP energy) "climbs" the RNA until it reaches the RNA polymerase. There it destabilizes the RNA/DNA duplex, favoring the release of the RNA polymerase from the DNA and the RNA from the DNA, as well. 2. In prokaryotes, tRNAs are the most altered (processed) RNAs. Modifications start with their being cleaved from a larger RNA containing both tRNAs and rRNAs. Ribonuclease P is a ribozyme (catalytic RNA) that cleaves the 5' end of tRNAs from the larger RNA. Ribonuclease III catalyzes excision of rRNAs from the larger molecule. 3. Eukaryotes and prokaryotes differ significantly in the relationship between transcription and translation. Prokaryotes have no nucleus. In them, translation starts oftentimes WHILE a message is being transcribed. There are no significant modifications to mRNAs in prokaryotes. 4. In eukaryotes, transcription and translation are spacially separated. Transcription occurs in the nucleus, whereas translation occurs in the cytoplasm. In addition, eukaryotic mRNAs are modified at the 5' end (capping), the 3' end (polyadenylation) and even in the middle (editing and splicing). 5. Eukaryotes have 3 specialized RNA polymerases. They differ in their sensitivity to alpha-amanitin (a poison from some mushrooms). RNA polymerase II (makes mRNAs) is the most sensitive. RNA polymerase III (makes tRNAs and small rRNA) has moderate sensitivity and RNA polymerase I (makes large rRNAs) has low sensitivity. 6. Sequence elements that affect transcription of eukaryotic genes. They include the TATA box (positioned approximately -30 to -100), and a CAAT box and GC box (-40 to -150). 7. The TATA box is not found in front of all eukaryotic genes, but is essential for strong transcription. 8. The promoters for each RNA polymerase are different in structure. I will not hold you responsible for their structures. 9. Enhancer sequence elements are DNA sequences that about bound by enhance (transcription factor) proteins. Enhancer proteins act in this way to enhance transcription of genes located up to many thousands of base pairs upstream (ahead of), downstream (down from ) or even in the middle of genes. 10. RNA Polymerase II in eukaryotes differs from RNA polymerase in E. coli in not binding to the DNA directly, but rather, it must bind to another protein that binds to the promoter first.
TRANSCRIPTION, TRANSLATION & THE FORMATION OF UREA & URIC ACID by Professor Fink
 
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Review of Transcription, Translation & the Formation of Urea & Uric Acid. The Lecture includes reference to the Gene locus (segment or exon), sense strand, RNA Polymerase, messenger (m-) RNA, ribosome, transfer (t-) RNA, codon (triplet), anticodon, peptide bonds, polypeptide chain, Genetic Mutations, Genetic Diseases The Lecture also reviews the metabolism (anabolism & catabolism) of Proteins and Nucleic Acids, including: deamination, Liver, urea, Nucleic Acids, nucleotides, uric acid, BUN, hyperuricemia, gouty Arthritis (gout). Check-out professor fink's web-site or additional resources in Biology, Anatomy, Physiology & Pharmacology: www.professorfink.com Down-loadable e-Books of the Lecture Outlines by Professor Fink can be purchased from the WLAC Bookstore at: https://wlac.redshelf.com/ “Hard Copy” Lecture Outlines can be purchased from the WLAC Bookstore at: http://onlinestore.wlac.edu/fink.asp
Views: 31929 professorfink
Why downregulation of genes involved in metabolism is observed in obese patients?
 
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By Fredrik Karpe, PhD, FRCP, Professor, Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK Produced by the International Chair on Cardiometabolic Risk
Views: 32 myhealthywaist
Prokaryotic regulation of gene expression
 
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How prokaryotes regulate how actively their genes are expressed (on or off, up or down). I discuss both negative gene regulation (involving repressors) and positive gene regulation (involving activators), discussing the classic trp and lac operon systems where this was first studied.
Views: 43840 BleierBiology
Regulation of gene expression | Wikipedia audio article
 
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This is an audio version of the Wikipedia Article: https://en.wikipedia.org/wiki/Regulation_of_gene_expression 00:01:52 1 Regulated stages of gene expression 00:02:32 2 Modification of DNA 00:03:07 2.1 Structural 00:03:45 2.2 Chemical 00:05:07 3 Regulation of transcription 00:06:47 4 Regulation of transcription in cancer 00:07:58 5 Regulation of transcription in addiction 00:10:10 6 Post-transcriptional regulation 00:10:52 7 Three prime untranslated regions and microRNAs 00:13:23 8 Regulation of translation 00:14:08 9 Examples of gene regulation 00:15:10 9.1 Developmental biology 00:16:33 10 Circuitry 00:16:42 10.1 Up-regulation and down-regulation 00:17:42 10.2 Inducible vs. repressible systems 00:19:00 10.3 Theoretical circuits 00:19:56 11 Study methods 00:22:22 12 See also 00:22:49 13 Notes and references 00:22:58 14 Bibliography 00:23:21 15 External links Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago. Learning by listening is a great way to: - increases imagination and understanding - improves your listening skills - improves your own spoken accent - learn while on the move - reduce eye strain Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone. Listen on Google Assistant through Extra Audio: https://assistant.google.com/services/invoke/uid/0000001a130b3f91 Other Wikipedia audio articles at: https://www.youtube.com/results?search_query=wikipedia+tts Upload your own Wikipedia articles through: https://github.com/nodef/wikipedia-tts Speaking Rate: 0.9227933974327304 Voice name: en-AU-Wavenet-B "I cannot teach anybody anything, I can only make them think." - Socrates SUMMARY ======= Regulation of gene expression, or gene regulation, includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products (protein or RNA). Sophisticated programs of gene expression are widely observed in biology, for example to trigger developmental pathways, respond to environmental stimuli, or adapt to new food sources. Virtually any step of gene expression can be modulated, from transcriptional initiation, to RNA processing, and to the post-translational modification of a protein. Often, one gene regulator controls another, and so on, in a gene regulatory network. Gene regulation is essential for viruses, prokaryotes and eukaryotes as it increases the versatility and adaptability of an organism by allowing the cell to express protein when needed. Although as early as 1951, Barbara McClintock showed interaction between two genetic loci, Activator (Ac) and Dissociator (Ds), in the color formation of maize seeds, the first discovery of a gene regulation system is widely considered to be the identification in 1961 of the lac operon, discovered by François Jacob and Jacques Monod, in which some enzymes involved in lactose metabolism are expressed by E. coli only in the presence of lactose and absence of glucose. In multicellular organisms, gene regulation drives cellular differentiation and morphogenesis in the embryo, leading to the creation of different cell types that possess different gene expression profiles from the same genome sequence. Although this does not explain how gene regulation originated, evolutionary biologists include it as a partial explanation of how evolution actually works at a molecular level, and it is central to the science of evolutionary developmental biology ("evo-devo"). The initiating event leading to a change in gene expression includes activation or deactivation of receptors.
Views: 5 Subhajit Sahu