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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: 260343 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: 1172527 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! 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: 111917 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: 25294 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: 568296 Amoeba Sisters
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
How Intracellular Receptors Regulate Gene Transcription HD Animation
 
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A ------------------------------- Please Like, comment, share and subscribe 👍🏻❤️
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: 26636 Audiopedia
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: 872 EDGE
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: 587250 Khan 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: 3562703 CrashCourse
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: 15876 iBiology
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: 42220 BleierBiology
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: 163131 Khan Academy
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: 1041525 Teacher's Pet
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: 1720651 Khan Academy
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: 866977 nature video
Regulation Of Lac Operon Animation
 
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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.
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: 1857192 SciShow
Regulation of Transcription
 
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Learn about the different regulatory elements that play a role in the regulation of transcription.
Views: 9482 Tracy Kovach
CRISPR-Cas9 Mediated Mouse Model Creation and Transcription Regulation - Haoyi Wang
 
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April 19-20, 2016 - Genomic Medicine Meeting IX: Bedside to Bench - Mind the Gaps. More: https://www.genome.gov/27564185
DNA transcription and translation [HD animation]
 
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DNA transcription and translation animation #Please → Like, comment, share and subscribe 👍🏻❤️
Views: 1290893 McGraw-Hill Animations
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: 624013 Bozeman Science
Upregulation Meaning
 
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Video shows what upregulation means. The process, in the regulation of gene expression, in which the number, or activity of receptors increases in order to increase sensitivity. Upregulation Meaning. How to pronounce, definition audio dictionary. How to say upregulation. Powered by MaryTTS, Wiktionary
Views: 1636 ADictionary
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: 103324 Shomu's Biology
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: 7738 Biology Professor
Downregulation and upregulation
 
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Downregulation and upregulation Contents 1 Downregulation and Upregulation of Receptors - Overview 2 Example: Insulin receptor downregulation 3 See also 4 References 5 Sources 6 External links Downregulation and Upregulation of Receptors - Overview Downregulation of receptors happens when receptors have been chronically exposed to an excessive amount of neurotransmitters, whether endogenous or drugs This results in ligand-induced desensitization or internalization of that receptor It is usually exhibited by various hormone receptors Upregulation of receptors, on the other hand, results in super-sensitized receptors especially after repeated exposure to the drug Within the regulation of gene expression, 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 cells sensitivity to the molecule This Downregulation and upregulation Click for more; https://www.turkaramamotoru.com/en/downregulation-and-upregulation-23452.html There are excerpts from wikipedia on this article and video
Views: 2108 Search Engine
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: 49 Brian Caesar
Genome regulation by long noncoding RNAs
 
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Genome regulation by long noncoding RNAs Air date: Wednesday, June 1, 2016, 3:00:00 PM Category: WALS - Wednesday Afternoon Lectures Runtime: 01:03:47 Description: NIH Director’s Wednesday Afternoon Lecture Series Dr. Chang’s research addresses how large sets of genes are turned on or off together, which is important in normal development, cancer, and aging. Chang discovered a new class of genes, termed long noncoding RNAs, can control gene activity throughout the genome, illuminating a new layer of biological regulation. He has invented new methods for defining the shapes of RNA and DNA genome-wide. The long term goal of his research is to decipher the regulatory information in the genome to benefit human health. For more information go to https://oir.nih.gov/wals Author: Howard Y. Chang, M.D., Ph.D., Stanford University Permanent link: http://videocast.nih.gov/launch.asp?19718
Views: 6082 nihvcast
Gene structure: upstream-Downstream....Promoter..TATA box..!!!
 
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Basic of structural elements of a gene!!!!
Views: 11009 Kawshik Academy
BIOLOGY GENE: EXPRESSION AND REGULATION NEET,AIIMS ,GATE ,GSCE ,BSC ,IIT JEE -MAINS,ADVANCED ,WBJEE
 
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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.
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: 55014 MEDSimplified
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: 356696 Khan Academy
Transcription and Translation: From DNA to Protein
 
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Ok, so everyone knows that DNA is the genetic code, but what does that mean? How can some little molecule be a code that makes a single cell develop into a giraffe, or a monkey, or Tony Danza? Within this clip lie the answers, child! Subscribe: http://bit.ly/ProfDaveSubscribe [email protected] http://patreon.com/ProfessorDaveExplains http://professordaveexplains.com http://facebook.com/ProfessorDaveExpl... http://twitter.com/DaveExplains General Chemistry Tutorials: http://bit.ly/ProfDaveGenChem Organic Chemistry Tutorials: http://bit.ly/ProfDaveOrgChem Biochemistry Tutorials: http://bit.ly/ProfDaveBiochem Classical Physics Tutorials: http://bit.ly/ProfDavePhysics1 Modern Physics Tutorials: http://bit.ly/ProfDavePhysics2 Mathematics Tutorials: http://bit.ly/ProfDaveMaths Biology Tutorials: http://bit.ly/ProfDaveBio American History Tutorials: http://bit.ly/ProfDaveAmericanHistory
Views: 1011743 Professor Dave Explains
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
 
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Paul Andersen describes the major mutations found in the living world. He starts with an analogy comparing the information in DNA with the information in a recipe. Changes in the DNA can result in changes to the protein, like changes in the recipe can result in changes in the food. He describes the three major point mutations; substitutions, deletions and insertions. He also describes several chromosomal mutations. 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: 814025 Bozeman Science
7.2 Transcription
 
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Views: 3227 Down Zero
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: 6756 ScienceVio
GENES & DNA REPLICATION by Professor Fink
 
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Review of Genes, Genetic Diseases & DNA Replication. The Lecture includes reference to Karyotyping, Autosomes, Sex Chromosomes (XX & XY), Genes, Genetic Mutations, Genetic Diseases, tumor suppressor genes, Oncogenes, BRCA, and p-53 Gene. Also discussed is Cell Division, DNA Replication, helicase and DNA polymerase. 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: 31508 professorfink
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: 224579 Katharina Petsche
Eukaryotic Gene Regulation Music Video
 
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Lyrics: Uh huh, this my cell All eukaryotes regulate like this This first step is DNA packing How does it fit in the nucleus? Wrap it around 8 histone proteins Not too tight cause it won’t transcribe Add some acetyl to the histone Make it looser for transcription Gotta find that TATA bo-ox Bind some transcription factors Ooh, for the RNA poly(merase), RNA poly(merase) Ooh, this my cell, this my cell Ooh, now enhance, now enhance Ooh, this my cell, this my cell You heard that we were enhancing But you need some activators Now the gene will fold together, speeding up the raaaaate So I’m ready to splice, gotta move exons Gotta make mRNA, go make some proteins That’s’ done, put your snurp-snurps down, getting every gene spliced up mRNA degradation But it’s not just gonna happen like that Cause you got a poly-A tail A 3 prime poly-A taaail mRNA degradation But it’s not just gonna happen like that Cause you got a GTP cap A 5 prime GTP cap Ooh, this my cell, this my cell Ooh, complex cells, complex cells Ooh, regulatin’, regulatin’ Ooh, this my cell, this my cell So here’s RNAi, little RNA segments No genes turned on, no proteins maaade Place a death tag on mRNA, and now it starts to degrade The cells gonna fight, gonna give its all Gonna stay alive, gonna regulate it That sucks cause the gene got silenced, another one bites the dust A few blocks in the translation stage So it’s not just attach to like that {point to ribosome} Cause of regulatory proteins O-o-n the 5 end A few blocks in the translation stage So it’s not just attach to like that {point to ribosome} Cause of lengthy tails O-o-n the 3 end Ooh, this my cell, this my cell Ooh, complex cells, complex cells Ooh, regulatin’, regulatin’ Ooh, this my cell, this my cell Let me hear you say this step is translation T-R-A-N-S-L-ation (This step is translation) (T-R-A-N-S-L-ation) Next The step is degradation D-E-G-R-A-D-ation (This step is degradation) (D-E-G-R-A-D-ation) A few parts in protein degradation Cause it’s not just gonna degrade like that Cause I got ubiquitin tags Proteasome degrade A few parts in protein processing Cause it’s not just gonna transport like that Gotta fold and cleave the protein And then add sugar groups Ooh, this my cell, this my cell Ooh, complex cells, complex cells Ooh, regulatin’, regulatin’ Ooh, this my cell, this my cell
Views: 384 Sophia Nguyen
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: 430 BiologyMonk
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: 2709627 Amoeba Sisters
Receptors in UNDER 5 MINUTES
 
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This video portrays the cell membrane and the proteins embedded in it: specifically the types of receptors. The cell membrane is made up of a phospholipid bilayer. It is fluid because the lipids within the bilayer are constantly moving. This movement is important for the proteins embedded in the cell membrane. Five types of functional proteins in the cell membrane are channels, transporters, enzymes, receptors, and structural proteins. Because of receptors, cells can send signals to each other. Receptors possess specific sites that can bind molecules, called ligands, non-covalently – this is called a “lock and key” mechanism. When a ligand binds to a receptor, the receptor’s shape changes, which then can alter the intracellular functions of the cell. There are 4 types of receptors: ligand-gated channels, enzyme-linked receptor, G-protein linked receptor, and intracellular receptor. The cell membrane does not let any hydrophilic molecules go through, and so it requires specific ligand gated channels for their movement. First the ligand binds to the receptor, then the channel opens to let the molecules through. Particularly sodium ions into the cell down their electrochemical gradient, and potassium ions out of the cell. In the enzyme-linked receptor the binding of the ligand changes the shape of the receptor and activates the enzymes on the inside of the cell. The ligand is referred to as a first messenger, and whatever is being activated would be a second messenger. An example of such activation would be a conversion of GTP into cyclic GMP. In G-protein coupled receptors the binding of the ligand causes the receptor to change its shape and in that changes the shape of a consecutive protein – G-protein. The G-protein can cause other things to happen, including activation of enzymes and opening of ion channels. There are some molecules which are able to pass through the cellular membrane, and such molecules can act on intracellular receptors. In this case when the ligand binds to the intracellular receptor – it can then alter the transcription of DNA within a cell. The programs used in the making of this video were Adobe Photoshop, Adobe After Effects, and Windows Movie Maker. We do not own any of the music in this video. They were obtained from: The Looney Tunes Theme Song, https://www.youtube.com/watch?v=euHrN2kZtMw and The Star Wars Ending Theme. Video made by: Anna Vasilevskaya Razan Bouzeineddine
Views: 118466 Rosie B
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: 113 Academy of One
Robert Tjian (Berkeley/HHMI) Part 1: Gene regulation: An introduction
 
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https://www.ibiology.org/genetics-and-gene-regulation/transcription-factors/ Transcription, the conversion of DNA to RNA, is one of the most fundamental processes in cell biology. However, only about 3% of our total DNA encodes genes to be transcribed. RNA polymerase II, the enzyme that transcribes DNA to RNA, relies on a large set of proteins known as transcription factors to recognize the coding sequences and to transcribe the correct genes, in the correct cell type, at the correct time. In Part 1 of his lecture, Tjian gives an overview of the complex and critical role that transcription factors play in regulating gene expression. How do different cells from the same organism, such as muscle cells, neurons and red blood cells, all of which have identical DNA, have such different phenotypes? Tjian addresses this question in his second lecture, where he expands on the mechanisms of gene regulation.
Views: 55468 iBiology
Signal Transduction Pathways
 
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038 - Signal Transduction Pathways.mov Paul Andersen explains how signal transduction pathways are used by cells to convert chemical messages to cellular action. Epinephrine is used as a sample messenger to trigger the release of glucose from cells in the liver. The G-Protein, adenylyl cyclase, cAMP, and protein kinases are all used as illustrative examples of signal transduction. A review of the concepts is also included. Do you speak another language? Help me translate my videos: http://www.bozemanscience.com/translations/ 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 of the images are licensed under creative commons and public domain licensing: "File:Dora and Boots.jpg." Wikipedia, the Free Encyclopedia, October 28, 2013. http://en.wikipedia.org/w/index.php?title=File:Dora_and_Boots.jpg&oldid=468219594. "File:Jimi Hendrix 1967 Uncropped.jpg." Wikipedia, the Free Encyclopedia. Accessed December 9, 2013. http://en.wikipedia.org/wiki/File:Jimi_Hendrix_1967_uncropped.jpg. "File:MarshallStack Slayer.jpg." Wikipedia, the Free Encyclopedia. Accessed December 9, 2013. http://en.wikipedia.org/wiki/File:MarshallStack_Slayer.jpg. "File:Pickup-SSH.jpg." Wikipedia, the Free Encyclopedia. Accessed December 9, 2013. http://en.wikipedia.org/wiki/File:Pickup-SSH.jpg. Juancoronado1974. English: Phospholipid Bilayer, November 23, 2013. Own work. http://commons.wikimedia.org/wiki/File:Bilayer.png.
Views: 977188 Bozeman Science
Gene Expression II - Kevin Ahern's BB 451 Lecture #49 2017
 
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Email me at [email protected] Friend me on Facebook at kevin.g.ahern. Highlights Gene Expression 1. The lactose operon consists of three linked structural genes that encode enzymes of lactose utilization, plus adjacent regulatory sites. The three enzymes --z, y, and a--encode beta-galactosidase, beta-galactoside permease (a transport protein), and thiogalactoside transacetylase (an enzyme of still unknown metabolic function), respectively. 2. Transcription of the lac operon commences at a promoter (lacP) to the left of lacZ and transcribes a polycistronic 5,200 nucleotide messenger RNA molecule (mRNA), ending at a terminator beyond lacA. Polycistronic, when referring to an RNA, means that more than one polypeptide chain is encoded by it. 3. The molecuke known as allolactose is an inducer of expression of the lac operon. It is made by the transacetylase of the lac operon. 4. 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 by preventing RNA Polymerase from binding to the promoter. 5. In the absence of inducer molecules, the lac repressor tightly binds to the operator and inhibits transcription. When inducer molecules are present, they bind to the lac repressor and change its shape and reduce its ability to bind the operator. 6. The promoter sequence of the lac operon differs somewhat from the ideal consensus sequence of an E. coli promoter. Consequently, in the absence of the CAP protein, the lac promoter does not function well on its own. 7. CAP must bind to cAMP in order to bind to the CAP region of the lac operon. When CAP 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 the promoter. 8. cAMP is made in bacterial cells when energy is low. Thus only when energy is low and lactose is present will the lac operon be transcribed abundantly. 9. When both CAP and the lac repressor are bound to the lac operon, the repressor 'wins', shutting down transcription of the operon. 10. The trp operon codes for proteins that synthesize tryptophan in bacterial cells. Only when tryptophan is in short supply is it desirable to have the operon transcribed. It has two levels of control. 11. The first operates like the lac operon. A repressor protein (trp repressor) can bind tryptophan. If it binds to tryptophan, then it binds to the trp operator and turns off transcription. 12. A second mechanism of controlling transcription of the trp operon is attenuation. Attenuation uses translation of a leader polypeptide to determine whether or not the cell has abundant tryptophan. 13. Attenuation operates through sequences in the 5' end of the trp operon mRNA in the leader peptide (a short sequence of the mRNA coding for a short polypeptide) that can form alternative base pairing structures. When tryptophan is low, the ribosome stalls in region 1 of the mRNA when awaiting tryptophan (in the coding region of the leader peptide). This stalling allows region 2 of the leader mRNA sequence to form base pairing with region 3. Such a pairing prevents region 3 from pairing with region 4. A region 3-4 pairing results in transcriptional termination and only occurs when there is abundant tryptophan (ribosome doesn't get stalled in region 1) 14. Riboswitches are tertiary structures in mRNA that bind to molecules and affect the transcription of the genes. They have two relevant regions - 1) an aptamer domain, which is the region of the mRNA where the molecule binds; and 2) a switching sequence that changes configuration as a result of binding to the aptamer domain. 15. Eukaryotic gene regulation is more complicated than that of prokaryotes due to the presence of histones and the much larger sizes of most eukaryotie genomes. 16. In eukaryotic cells, DNA is wrapped up (coiled up) with basic proteins called histones. 17. Four histones form a core around which DNA is wrapped. This core contains two copies each of histones H2A, H2B, H3, and H4. 18. The appearance of chromatin DNA when partly unwound and examined closely resembles that of beads on a string. 19. Histones of the octamer have strong structural similarity to each other. 20. 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. 21. Enhancer sequences are bound by enhancer proteins. Binding of enhancer proteins to enhancer sequences allows for tissue specific expression of genes. Enhancer proteins help to "clear" out the histones from a region of a chromosome to allow transcription to occur.
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THE ADENOHYPOPHYSIS, THYROTROPIN & THE REGULATION OF THYROXIN by Professor Fink
 
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In this video lecture, Professor Fink reviews the role of the Hypothalamic Releasing Hormones on the Adenohypophysis (Anterior Lobe of the Pituitary Gland) in general, and then describes the Regulation of Thyroxin via TRH and Thyrotropin (TSH) in particular. Included in the detailed discussion is the Negative Feedback Loop involved in homeostatically maintaining circulating plasma Thyroxin levels. Reference is made to T4 & T3, the actions of Thyroxin, Hypothyroidism (Primary, Secondary & Tertiary), Hyperthyroidism, Cretinism, and the clinically-characteristic TSH (Thyrotropin) levels in Hypothyroidism. 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
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