Lecture 9 Controlling gene expression

Size: px
Start display at page:

Download "Lecture 9 Controlling gene expression"

Transcription

1 Lecture 9 Controlling gene expression BIOLOGY Campbell, Reece and Mitchell Chapter ( ) Every cell in your body contains the same number of genes approximately 35, 000 DNA is wound around histone proteins chromatin eukaryotes But in any given tissue or cell type most of these genes are turned off i.e. they are not being expressed In different cell types, different cell-specific sets of genes are turned on i.e. are expressed e.g. in mature red blood cells very few genes are expressed A single gene coding for hemoglobin is expressed at very high levels in these cells. 1

2 Gene expression is highly regulated Many aspects of gene expression are very tightly regulated e.g. When and for how long a gene will be expressed e.g. some genes are expressed for only a few hours during development of the embryo and are never expressed in the adult Where a gene will be expressed i.e. in what cell and tissue types e.g. hemoglobin is only expressed in one cell type the red blood cells How much expression i.e. low or high levels of expression In plants the RUBISCO gene plays a major role in photosynthesis It codes for the most abundantly expressed protein in leaves = 50% of the total protein i.e. the gene is very highly expressed 2

3 The expression of many genes may also be regulated in response to external factors e.g. the gene coding for RUBISCO shows two types of regulation: (1) Regulation by light RUBISCO is only expressed if leaves are exposed to light there is no expression in the dark (2) Tissue-specific regulation RUBISCO is only expressed in green tissues (e.g. leaves) - it is not expressed in root tissue (even if exposed to light) Hox Genes Control development Hox genes need to be highly regulated to get expressed at the right time and correct level to orchestrate mammalian development in utero. Mario Capecchi won the Nobel Prize in 2007 for his research on Hox genes & their role in defining the mammalian development plan. Individual Hox genes were mutated in mice and the effects of the mutations observed. In TCD last week at History Society! 3

4 How might gene expression be regulated? There are several potential control points in the gene expression pathway: 1. Control of transcription 2. Control via mrna processing (not in bacteria) 3. Control of translation 4

5 ww.google.ie/imgres?imgurl= transcriptional_regulation_technologies_- _Erin_Zwack&usg= CNiMsnSqWcsTc79Ltb2qTTYq1iA=&h=683&w=600&sz=62&hl=en&start=24&zoom=1&tbnid=6aBZYKt9b8l1dM:&tbnh=139&tbnw=122&ei=3XJvUozDJO_n7AaO0oDo CQ&prev=/search%3Fq%3Dcontrol%2Bof%2Bgene%2Bexpression%2Bin%2Beukaryotes%26start%3D20%26um%3D1%26sa%3DN%26hl%3Den%26gbv%3D2%26tbm %3Disch&um=1&itbs=1&sa=X&ved=0CDAQrQMwAzgU 3 bases of DNA (a codon) codes for 3 bases of RNA which codes for a single amino acid. The last codon of a run of codons coding for amino acids is called a stop codon a signal to stop coding. Mature RNAs (mrnas) without a stop codon are degraded rapidly the cell has methods to get rid of aberrant RNAs the cell is always double checking things! Dr. Ambro van Hoof, University of Texas,, Houston 5

6 sandwalk.blogspot.com prokayotic gene.jpg faculty.ksu.edu.san noncoding.gens.jpg While approx. 95% of DNA does not code for protein, we are now realising that approx. 1/3 of DNA in the mammalian genome codes for non-coding RNAs (that is they never get translated into proteins). It turns out that these non-coding RNAs are important in regulating gene expression. One class of non-coding RNAs involved in this is micrornas. 6

7 Transcription in bacteria - prokaryotes 1. Transcription requires the enzyme RNA polymerase 2. To initiate transcription, RNA polymerase must bind to a special DNA sequence at the start of the gene called a promoter. RNA pol promoter gene 3. If RNA polymerase is prevented from binding to the promoter, transcription will not occur Inducible gene expression in bacteria Bacteria can adapt their metabolism to take advantage of nutrients in the environment E. coli prefers glucose to all other sugars as a carbon source However, if no glucose is available, it can use other sugars like the sugar present in milk = lactose E. coli can respond very rapidly, within 15 minutes, to take advantage of the availability of lactose It responds by rapidly expressing 3 genes which code for enzymes that are required for lactose metabolism Expression of these genes is said to be induced by lactose 7

8 The 3 enzymes required for lactose metabolism are translated from the single mrna transcript: The enzymes are: (i) Lactose permease which is encoded by the lacy gene It functions as a membrane transporter which imports lactose from outside the cell (ii) Beta-galactosidase which is encoded by the lacz gene It functions to hydrolyse lactose to the monosaccharides glucose and galactose (iii) Transacetylase which is encoded by the laca gene It precise function is not fully known, howevr it an enzyme that transfers an acetyl group from acetyl-coa to β-galactosides The 3 genes: lacz, lacy and laca are found side-by-side as a single transcription unit This means that a single mrna molecule is transcribed DNA mrna lacz lacy laca lacz lacy laca This type of gene organization, where genes that function in the same metabolic pathway are grouped together is called an operon Because these genes are all involved in lactose metabolism this group is called the lactose operon or the lac operon 8

9 Lactose induces expression of the lac operon A. If lactose is not present in the environment: The lac operon is not being actively transcribed (i.e. turned OFF) The 3 enzymes required for lactose metabolism are present in extremely low amounts B. If lactose is present in the environment: Transcription of the lac operon is induced Within 15 minutes expression of the operon increases by approximately 1000 fold How is the lac operon turned OFF if lactose is absent? How does lactose induce expression of the lac operon? Answers: 1. The operon contains a 4 th gene called laci that codes for a regulatory protein (not an enzyme!) 2. This protein functions as a repressor of transcription 3. The repressor binds to a DNA sequence called the operator located between the promoter and the 3 genes lacz, lacy, laca 4. When the repressor is bound to the operator, RNA polymerase cannot bind to the promoter. 9

10 The repressor stays bound to the operator sequence as long as lactose is absent. This prevents RNA polymerase from binding to the promoter LacI lacy laca LacI Induction of transcription by lactose Lactose binds to repressor and changes its shape. Repressor can no longer bind to the operator. This allows RNA polymerase to bind to the promoter and begin transcription promoter operator 10

11 Summary In bacteria, genes that carry out related functions are usually grouped together to form a regulatory unit the operon Operons contain at least one gene whose protein product functions to regulate transcription of the operon In the case of the lac operon, the laci gene codes for a repressor protein that is normally found bound to the operator Transcription of the lac operon is inducible by the sugar lactose If lactose is present, it binds to the repressor and changes its affinity for the operator. When the repressor vacates the operator, RNA polymerase can bind to the promoter and begin transcription. 11

12 (EM: David E and Ada L Olins) Eukaryotes Mimimal Transcriptional Machinery Minimal complex FJ Asturias 2004 Current Opinion in Structural Biology 14: RNA polymerase II, Transcription factor IIF Transcription factor IIB TATA binding protein TBP Minimal complex capable of promoter directed initiation 12

13 Nature Reviews Vaquerizas et al. April 2009 Nature Reviews Vaquerizas et al. April 2009 Hox gene clusters on chromsomes 2, 7, 12 & 17 13

GENE REGULATION IN PROKARYOTES

GENE REGULATION IN PROKARYOTES GENE REGULATION IN PROKARYOTES Prepared by Brenda Leady, University of Toledo Copyright (c) The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1 Gene regulation refers to

More information

REGULATION OF GENE EXPRESSION

REGULATION OF GENE EXPRESSION REGULATION OF GENE EXPRESSION Each cell of a living organism contains thousands of genes. But all genes do not function at a time. Genes function according to requirements of the cell. Genes control the

More information

Gene Expression. Lesson 6

Gene Expression. Lesson 6 Gene Expression Lesson 6 Regulation of gene expression Gene regulation turning on or off specific genes depending on the requirements of an organism Housekeeping genes are always switched on (vital life

More information

Control of Gene Expression

Control of Gene Expression Control of Gene Expression 1 How Gene Regulation Works 2 Control of Gene Expression Controlling gene expression is often accomplished by controlling transcription initiation Regulatory proteins bind to

More information

REGULATION OF GENE EXPRESSION

REGULATION OF GENE EXPRESSION REGULATION OF GENE EXPRESSION Each cell of a living organism contains thousands of genes. But all genes do not function at a time. Genes function according to requirements of the cell. Genes control the

More information

Regulation of Gene Expression

Regulation of Gene Expression Chapter 18 Regulation of Gene Expression Edited by Shawn Lester PowerPoint Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley

More information

CHAPTER 13 LECTURE SLIDES

CHAPTER 13 LECTURE SLIDES CHAPTER 13 LECTURE SLIDES Prepared by Brenda Leady University of Toledo To run the animations you must be in Slideshow View. Use the buttons on the animation to play, pause, and turn audio/text on or off.

More information

Differences between prokaryotes & eukaryotes. Gene function

Differences between prokaryotes & eukaryotes. Gene function GENE REGULATION Differences between prokaryotes & eukaryotes Gene function Description of Prokaryotic Chromosome and E.coli Review Differences between Prokaryotic & Eukaryotic Chromosomes Four differences

More information

Synthetic cells: do bacteria need all its genes? No.

Synthetic cells: do bacteria need all its genes? No. NO NEED TO REFER TO THE SLIDES. بسم هللا الرحمن الرحيم Do we need all the non coding regions of the DNA? Two weeks ago, they discovered that the genome of a plant is very small (recall that plant genome

More information

GENE REGULATION. Gene regulation occurs at the level of transcription or production of mrna

GENE REGULATION. Gene regulation occurs at the level of transcription or production of mrna GENE REGULATION Virtually every cell in your body contains a complete set of genes But they are not all turned on in every tissue Each cell in your body expresses only a small subset of genes at any time

More information

Transcriptional Regulation

Transcriptional Regulation Transcriptional Regulation Gene expression responds to environmental conditions. Some regulatory proteins are present at only 5 10 copies, whereas under certain conditions, the expression of these proteins

More information

Regulation of gene expression. (Lehninger pg )

Regulation of gene expression. (Lehninger pg ) Regulation of gene expression (Lehninger pg. 1072-1085) Today s lecture Gene expression Constitutive, inducible, repressible genes Specificity factors, activators, repressors Negative and positive gene

More information

Molecular Cell Biology - Problem Drill 09: Gene Expression in Prokaryotes

Molecular Cell Biology - Problem Drill 09: Gene Expression in Prokaryotes Molecular Cell Biology - Problem Drill 09: Gene Expression in Prokaryotes Question No. 1 of 10 1. Which of the following statements about gene expression in prokaryotes is correct? Question #1 (A) In prokaryotes,

More information

Chapter 13 - Regulation of Gene Expression

Chapter 13 - Regulation of Gene Expression Chapter 13 - Regulation of Gene Expression 1. Describe the typical components of an operon in an E. coli (prokaryotic) cell. (p. 238-239) a. regulator gene - b. promoter - c. operator - d. structural gene

More information

Prokaryotic Transcription

Prokaryotic Transcription Prokaryotic Transcription Contents 1 The Lactose Intolerance of Bacteria 2 The Lac Operon 3 Lac Operon Simulation 4 LacZ as a reporter gene The Lactose Intolerance of Bacteria The standard growth kinetics

More information

Chapter 18: Regulation of Gene Expression. 1. Gene Regulation in Bacteria 2. Gene Regulation in Eukaryotes 3. Gene Regulation & Cancer

Chapter 18: Regulation of Gene Expression. 1. Gene Regulation in Bacteria 2. Gene Regulation in Eukaryotes 3. Gene Regulation & Cancer Chapter 18: Regulation of Gene Expression 1. Gene Regulation in Bacteria 2. Gene Regulation in Eukaryotes 3. Gene Regulation & Cancer Gene Regulation Gene regulation refers to all aspects of controlling

More information

Gene Circuits -2. Shu-Ping Lin, Ph.D. Institute of Biomedical Engineering

Gene Circuits -2. Shu-Ping Lin, Ph.D. Institute of Biomedical Engineering Gene Circuits -2 Shu-Ping Lin, Ph.D. Institute of Biomedical Engineering E-mail: splin@dragon.nchu.edu.tw Website: http://web.nchu.edu.tw/pweb/users/splin/ Genes Flow of information in gene expression

More information

Regulation of Gene Expression

Regulation of Gene Expression Slide 1 Chapter 18 Regulation of Gene Expression PowerPoint Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions

More information

BIOLOGY. Chapter 16 GenesExpression

BIOLOGY. Chapter 16 GenesExpression BIOLOGY Chapter 16 GenesExpression CAMPBELL BIOLOGY TENTH EDITION Reece Urry Cain Wasserman Minorsky Jackson 18 Gene Expression 2014 Pearson Education, Inc. Figure 16.1 Differential Gene Expression results

More information

Control of Metabolic Processes

Control of Metabolic Processes Control of Metabolic Processes Harriet Wilson, Lecture Notes Bio. Sci. 4 - Microbiology Sierra College As described earlier, the metabolic processes occurring within living organisms (glycolysis, respiration,

More information

7.1 The lac Operon 7-1

7.1 The lac Operon 7-1 7.1 The lac Operon The lac operon was the first operon discovered It contains 3 genes coding for E. coli proteins that permit the bacteria to use the sugar lactose Galactoside permease (lacy) which transports

More information

Chapter 18: Regulation of Gene Expression

Chapter 18: Regulation of Gene Expression Chapter 18: Regulation of Gene Expression Regulation of Metabolism Shuts off transcription Types of Feedback Negative feedback = body s response is to reduce the stimulus Ex: regulation of body temp, blood

More information

Name: Class: Date: ID: A

Name: Class: Date: ID: A Class: _ Date: _ CH 12 Review Multiple Choice Identify the choice that best completes the statement or answers the question. 1. How many codons are needed to specify three amino acids? a. 6 c. 3 b. 12

More information

The Lactose Intolerance of Bacteria

The Lactose Intolerance of Bacteria Contents 1 The Lactose Intolerance of Bacteria 2 The Lac Operon 3 Lac Operon Simulation 4 LacZ as a reporter gene 5 Blue-White Screening 6 References The Lactose Intolerance of Bacteria The standard growth

More information

GENE REGULATION slide shows by Kim Foglia modified Slides with blue edges are Kim s

GENE REGULATION slide shows by Kim Foglia modified Slides with blue edges are Kim s GENE REGULATION slide shows by Kim Foglia modified Slides with blue edges are Kim s 2007-2008 Bacterial metabolism Bacteria need to respond quickly to changes in their environment STOP GO if they have

More information

Section C: The Control of Gene Expression

Section C: The Control of Gene Expression Section C: The Control of Gene Expression 1. Each cell of a multicellular eukaryote expresses only a small fraction of its genes 2. The control of gene expression can occur at any step in the pathway from

More information

Chapter 18. Regulation of Gene Expression

Chapter 18. Regulation of Gene Expression Chapter 18 Regulation of Gene Expression 2007-2008 Control of Prokaryotic (Bacterial) Genes 2007- Bacterial metabolism Bacteria need to respond quickly to changes in their environment STOP GO if they have

More information

Chapter 15 Gene Regulation in Prokaryotes

Chapter 15 Gene Regulation in Prokaryotes Chapter 15 Gene Regulation in Prokaryotes 17-1 Sections to study 15.1 The elements of prokaryotic gene expression 15.2 Regulation of transcription initiation via DNA-binding proteins 15.3 RNA-mediated

More information

Ch. 10 Notes DNA: Transcription and Translation

Ch. 10 Notes DNA: Transcription and Translation Ch. 10 Notes DNA: Transcription and Translation GOALS Compare the structure of RNA with that of DNA Summarize the process of transcription Relate the role of codons to the sequence of amino acids that

More information

Regulation of Gene Expression

Regulation of Gene Expression CAMPBELL BIOLOGY IN FOCUS URRY CAIN WASSERMAN MINORSKY REECE 15 Regulation of Gene Expression Lecture Presentations by Kathleen Fitzpatrick and Nicole Tunbridge, Simon Fraser University SECOND EDITION

More information

Chromosomal Mutations. 2. Gene Mutations

Chromosomal Mutations. 2. Gene Mutations 12-4 12-4 1. Chromosomal 3. NOT! 2. Gene A genetic mutation is any change in the DNA nucleotide sequence. Mutation is caused by mistakes during DNA replication, as well as mutagens, like certain chemicals

More information

Summary 12 1 DNA RNA and Protein Synthesis Chromosomes and DNA Replication. Name Class Date

Summary 12 1 DNA RNA and Protein Synthesis Chromosomes and DNA Replication. Name Class Date Chapter 12 Summary DNA and RNA 12 1 DNA To understand genetics, biologists had to learn the chemical structure of the gene. Frederick Griffith first learned that some factor from dead, disease-causing

More information

Computational Biology I LSM5191 (2003/4)

Computational Biology I LSM5191 (2003/4) Computational Biology I LSM5191 (2003/4) Aylwin Ng, D.Phil Lecture Notes: Transcriptome: Molecular Biology of Gene Expression I Flow of information: DNA to polypeptide DNA Start Exon1 Intron Exon2 Termination

More information

AP Biology Gene Expression/Biotechnology REVIEW

AP Biology Gene Expression/Biotechnology REVIEW AP Biology Gene Expression/Biotechnology REVIEW Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Gene expression can be a. regulated before transcription.

More information

Gene expression DNA RNA. Protein DNA. Replication. Initiation Elongation Processing Export. DNA RNA Protein. Transcription. Degradation.

Gene expression DNA RNA. Protein DNA. Replication. Initiation Elongation Processing Export. DNA RNA Protein. Transcription. Degradation. Gene expression DNA RNA Protein DNA DNA Degradation RNA Degradation Protein Replication Transcription Translation Initiation Elongation Processing Export Initiation Elongation Processing Targeting Chapter

More information

Prokaryotic Transcription

Prokaryotic Transcription Prokaryotic Transcription Transcription Basics DNA is the genetic material Nucleic acid Capable of self-replication and synthesis of RNA RNA is the middle man Nucleic acid Structure and base sequence are

More information

Biol 3301 Genetics Exam #2A October 26, 2004

Biol 3301 Genetics Exam #2A October 26, 2004 Biol 3301 Genetics Exam #2A October 26, 2004 This exam consists of 40 multiple choice questions worth 2.5 points each, for a total of 100 points. Good luck. Name SS# 1. Which of the following statements

More information

Chapter 18: Regulation of Gene Expression. Gene Regulation. Transcription Factors 3/21/2017

Chapter 18: Regulation of Gene Expression. Gene Regulation. Transcription Factors 3/21/2017 Chapter 18: Regulation of Gene Expression 1. Gene Regulation in Bacteria 2. Gene Regulation in Eukaryotes 3. Gene Regulation & Cancer Gene Regulation Gene regulation refers to all aspects of controlling

More information

Chapter 11. How Genes Are Controlled. Lectures by Edward J. Zalisko

Chapter 11. How Genes Are Controlled. Lectures by Edward J. Zalisko Chapter 11 How Genes Are Controlled PowerPoint Lectures for Campbell Essential Biology, Fifth Edition, and Campbell Essential Biology with Physiology, Fourth Edition Eric J. Simon, Jean L. Dickey, and

More information

How to Use This Presentation

How to Use This Presentation How to Use This Presentation To View the presentation as a slideshow with effects select View on the menu bar and click on Slide Show. To advance through the presentation, click the right-arrow key or

More information

Reading Lecture 3: 24-25, 45, Lecture 4: 66-71, Lecture 3. Vectors. Definition Properties Types. Transformation

Reading Lecture 3: 24-25, 45, Lecture 4: 66-71, Lecture 3. Vectors. Definition Properties Types. Transformation Lecture 3 Reading Lecture 3: 24-25, 45, 55-66 Lecture 4: 66-71, 75-79 Vectors Definition Properties Types Transformation 56 VECTORS- Definition Vectors are carriers of a DNA fragment of interest Insert

More information

I. To understand Genetics - A. Chemical nature of genes had to be discovered B. Allow us to understand how genes control inherited characteristics

I. To understand Genetics - A. Chemical nature of genes had to be discovered B. Allow us to understand how genes control inherited characteristics Ch 12 Lecture Notes - DNA I. To understand Genetics - A. Chemical nature of genes had to be discovered B. Allow us to understand how genes control inherited characteristics 1 II. Griffith and Transformation

More information

I. Prokaryotic Gene Regulation. Figure 1: Operon. Operon:

I. Prokaryotic Gene Regulation. Figure 1: Operon. Operon: I. Prokaryotic Gene Regulation Figure 1: Operon Operon: a) Regulatory Elements consist of an Operator that serves as the on-off switch for the genes of the operon. Also contains a promoter for the Structural

More information

Green Fluorescent Protein (GFP) Purification. Hydrophobic Interaction Chromatography

Green Fluorescent Protein (GFP) Purification. Hydrophobic Interaction Chromatography Green Fluorescent Protein (GFP) Purification Hydrophobic Interaction Chromatography What is the GFP gene? GFP is a green fluorescent protein that is normally found in jellyfish. It has been engineered

More information

Handouts: 15A -- Induction vs Repression; Repression vs Feedback Inhibition & 15 B -- Operons

Handouts: 15A -- Induction vs Repression; Repression vs Feedback Inhibition & 15 B -- Operons C2005/F2401 '08 -- Lecture 15 -- Last Edited: 10/29/08 03:13 PM Copyright 2008 Deborah Mowshowitz and Lawrence Chasin Department of Biological Sciences Columbia University New York, NY. Handouts: 15A --

More information

Pearson Education Limited Edinburgh Gate Harlow Essex CM20 2JE England and Associated Companies throughout the world

Pearson Education Limited Edinburgh Gate Harlow Essex CM20 2JE England and Associated Companies throughout the world Pearson Education Limited Edinburgh Gate Harlow Essex CM20 2JE England and Associated Companies throughout the world Visit us on the World Wide Web at: www.pearsoned.co.uk Pearson Education Limited 2014

More information

Name Class Date. Practice Test

Name Class Date. Practice Test Name Class Date 12 DNA Practice Test Multiple Choice Write the letter that best answers the question or completes the statement on the line provided. 1. What do bacteriophages infect? a. mice. c. viruses.

More information

Biology 3201 Genetics Unit #5

Biology 3201 Genetics Unit #5 Biology 3201 Genetics Unit #5 Protein Synthesis Protein Synthesis Protein synthesis: this is the process whereby instructions from DNA are used to create polypeptides that make up a protein. This process

More information

Chapter 14 Regulation of Transcription

Chapter 14 Regulation of Transcription Chapter 14 Regulation of Transcription Cis-acting sequences Distance-independent cis-acting elements Dissecting regulatory elements Transcription factors Overview transcriptional regulation Transcription

More information

Developmental Biology BY1101 P. Murphy

Developmental Biology BY1101 P. Murphy Developmental Biology BY1101 P. Murphy Lecture 7 Cellular differentiation and the regulation of gene expression. In this lecture we looked at two main questions: How is gene expression regulated? (revision

More information

Gene Regulation in Eukaryotes

Gene Regulation in Eukaryotes Gene Regulation in Eukaryotes The latest estimates are that a human cell, a eukaryotic cell, contains 20,000 25,000 genes. Some of these are expressed in all cells all the time. These so-called housekeeping

More information

12 1 DNA. Slide 1 of 37. End Show. Copyright Pearson Prentice Hall:

12 1 DNA. Slide 1 of 37. End Show. Copyright Pearson Prentice Hall: 12 1 DNA 1 of 37 http://www.biologyjunction.com/powerpoints_dragonfly_book_prent.htm 12 1 DNA Griffith and Transformation Griffith and Transformation In 1928, Fredrick Griffith was trying to learn how

More information

Practice Exam A. Briefly describe how IL-25 treatment might be able to help this responder subgroup of liver cancer patients.

Practice Exam A. Briefly describe how IL-25 treatment might be able to help this responder subgroup of liver cancer patients. Practice Exam 2007 1. A special JAK-STAT signaling system (JAK5-STAT5) was recently identified in which a gene called TS5 becomes selectively transcribed and expressed in the liver upon induction by a

More information

Chapter 11: Regulation of Gene Expression

Chapter 11: Regulation of Gene Expression Chapter Review 1. It has long been known that there is probably a genetic link for alcoholism. Researchers studying rats have begun to elucidate this link. Briefly describe the genetic mechanism found

More information

However, only a fraction of these genes are transcribed in an individual cell at any given time.

However, only a fraction of these genes are transcribed in an individual cell at any given time. All cells in an organism contain the same set of genes. However, only a fraction of these genes are transcribed in an individual cell at any given time. It is the pattern of gene expression that determines

More information

Chapter 2. An Introduction to Genes and Genomes

Chapter 2. An Introduction to Genes and Genomes PowerPoint Lectures for Introduction to Biotechnology, Second Edition William J.Thieman and Michael A.Palladino Chapter 2 An Introduction to Genes and Genomes Lectures by Lara Dowland Chapter Contents

More information

What is RNA? Another type of nucleic acid A working copy of DNA Does not matter if it is damaged or destroyed

What is RNA? Another type of nucleic acid A working copy of DNA Does not matter if it is damaged or destroyed RNA Section 3.1 What is RNA? Another type of nucleic acid A working copy of DNA Does not matter if it is damaged or destroyed Used to direct the production of proteins that determines an organisms characteristics

More information

CHAPTERS , 17: Eukaryotic Genetics

CHAPTERS , 17: Eukaryotic Genetics CHAPTERS 14.1 14.6, 17: Eukaryotic Genetics 1. Review the levels of DNA packing within the eukaryote nucleus. Label each level. (A similar diagram is on pg 188 of your textbook.) 2. How do the coding regions

More information

DNA Structure and Properties Basic Properties Predicting Melting Temperature. Dinesh Yadav

DNA Structure and Properties Basic Properties Predicting Melting Temperature. Dinesh Yadav DNA Structure and Properties Basic Properties Predicting Melting Temperature Dinesh Yadav Nucleic Acid Structure Question: Is this RNA or DNA? Molecules of Life, pp. 15 2 Nucleic Acid Bases Molecules of

More information

Lecture Series 10 The Genetics of Viruses and Prokaryotes

Lecture Series 10 The Genetics of Viruses and Prokaryotes Lecture Series 10 The Genetics of Viruses and Prokaryotes The Genetics of Viruses and Prokaryotes A. Using Prokaryotes and Viruses for Genetic Experiments B. Viruses: Reproduction and Recombination C.

More information

Chapter 18. The Exciting World Of Bacterial Genetics

Chapter 18. The Exciting World Of Bacterial Genetics Chapter 18. The Exciting World Of Bacterial Genetics Why study bacterial genetics? Its an easy place to start history we know more about it systems better understood simpler genome good model for control

More information

What can you remember about enzymes? Mr W

What can you remember about enzymes? Mr W What can you remember about enzymes? Mr W Human Cells (f) Enzymes and Metabolism Learning Intentions Describe metabolism, synthetic (energy requiring) and breakdown (energy releasing) pathways Cell Metabolism

More information

Nucleic Acid Structure:

Nucleic Acid Structure: Nucleic Acid Structure: Purine and Pyrimidine nucleotides can be combined to form nucleic acids: 1. Deoxyribonucliec acid (DNA) is composed of deoxyribonucleosides of! Adenine! Guanine! Cytosine! Thymine

More information

BCH 4054 Fall 2000 Chapter 31 Lecture Notes

BCH 4054 Fall 2000 Chapter 31 Lecture Notes BCH 4054 Fall 2000 Chapter 31 Lecture Notes 1 Chapter 31 Transcription and Regulation of Gene Expression 2 Messenger RNA Central Dogma (Francis Crick, 1958) DNA RNA Protein (Fig 31.1) Jacob-Monod Hypothesis:

More information

UNIT 3B. Yesterday s Picture DNA RNA. protein

UNIT 3B. Yesterday s Picture DNA RNA. protein Warm-Up Insulin is a protein hormone released into the bloodstream by the pancreas to regulate blood glucose (sugar) levels. Describe how insulin is secreted by pancreatic cells. Use at least FOUR organelles,

More information

UNIT 3B. Yesterday s Picture DNA RNA. protein

UNIT 3B. Yesterday s Picture DNA RNA. protein Warm-Up Insulin is a protein hormone released into the bloodstream by the pancreas to regulate blood glucose (sugar) levels. Describe how insulin is secreted by pancreatic cells. Use at least FOUR organelles,

More information

Genetics Lecture Notes Lectures 17 19

Genetics Lecture Notes Lectures 17 19 Genetics Lecture Notes 7.03 2005 Lectures 17 19 Lecture 17 Gene Regulation We are now going to look at ways that genetics can be used to study gene regulation. The issue is how cells adjust the expression

More information

From DNA to Protein: Genotype to Phenotype

From DNA to Protein: Genotype to Phenotype 12 From DNA to Protein: Genotype to Phenotype 12.1 What Is the Evidence that Genes Code for Proteins? The gene-enzyme relationship is one-gene, one-polypeptide relationship. Example: In hemoglobin, each

More information

Module 3. Lecture 5. Regulation of Gene Expression in Prokaryotes

Module 3. Lecture 5. Regulation of Gene Expression in Prokaryotes Module 3 Lecture 5 Regulation of Gene Expression in Prokaryotes Recap So far, we have looked at prokaryotic gene regulation using 3 operon models. lac: a catabolic operon which displays induction via negative

More information

Note: Please use the actual date you accessed this material in your citation.

Note: Please use the actual date you accessed this material in your citation. MIT OpenCourseWare http://ocw.mit.edu 7.012 Introduction to Biology, Fall 2004 Please use the following citation format: Eric Lander, Robert Weinberg, and Claudette Gardel, 7.012 Introduction to Biology,

More information

Transcription in Eukaryotes

Transcription in Eukaryotes Transcription in Eukaryotes Biology I Hayder A Giha Transcription Transcription is a DNA-directed synthesis of RNA, which is the first step in gene expression. Gene expression, is transformation of the

More information

Lac Operon contains three structural genes and is controlled by the lac repressor: (1) LacY protein transports lactose into the cell.

Lac Operon contains three structural genes and is controlled by the lac repressor: (1) LacY protein transports lactose into the cell. Regulation of gene expression a. Expression of most genes can be turned off and on, usually by controlling the initiation of transcription. b. Lactose degradation in E. coli (Negative Control) Lac Operon

More information

Chapter 12 Packet DNA 1. What did Griffith conclude from his experiment? 2. Describe the process of transformation.

Chapter 12 Packet DNA 1. What did Griffith conclude from his experiment? 2. Describe the process of transformation. Chapter 12 Packet DNA and RNA Name Period California State Standards covered by this chapter: Cell Biology 1. The fundamental life processes of plants and animals depend on a variety of chemical reactions

More information

# Date Title Page # 1. 01/20/15 Chapter 11: Genetics /09/15 Chapter 14: Human Genetics /05/15 Chapter 12: DNA and RNA 49

# Date Title Page # 1. 01/20/15 Chapter 11: Genetics /09/15 Chapter 14: Human Genetics /05/15 Chapter 12: DNA and RNA 49 Table of Contents # Date Title Page # 1. 01/20/15 Chapter 11: Genetics 1 2. 02/09/15 Chapter 14: Human Genetics 28 3. 03/05/15 Chapter 12: DNA and RNA 49 i 1 03/06/14 Ch. 12: DNA 49 Objective: Students

More information

Chapter 17 Lecture. Concepts of Genetics. Tenth Edition. Regulation of Gene Expression in Eukaryotes

Chapter 17 Lecture. Concepts of Genetics. Tenth Edition. Regulation of Gene Expression in Eukaryotes Chapter 17 Lecture Concepts of Genetics Tenth Edition Regulation of Gene Expression in Eukaryotes Chapter Contents 17.1 Eukaryotic Gene Regulation Can Occur at Any of the Steps Leading from DNA to Protein

More information

Gene Expression: Transcription, Translation, RNAs and the Genetic Code

Gene Expression: Transcription, Translation, RNAs and the Genetic Code Lecture 28-29 Gene Expression: Transcription, Translation, RNAs and the Genetic Code Central dogma of molecular biology During transcription, the information in a DNA sequence (a gene) is copied into a

More information

32 Gene regulation in Eukaryotes Lecture Outline 11/28/05. Gene Regulation in Prokaryotes and Eukarykotes

32 Gene regulation in Eukaryotes Lecture Outline 11/28/05. Gene Regulation in Prokaryotes and Eukarykotes 3 Gene regulation in Eukaryotes Lecture Outline /8/05 Gene regulation in eukaryotes Chromatin remodeling More kinds of control elements Promoters, Enhancers, and Silencers Combinatorial control Cell-specific

More information

DNA Transcription. Dr Aliwaini

DNA Transcription. Dr Aliwaini DNA Transcription 1 DNA Transcription-Introduction The synthesis of an RNA molecule from DNA is called Transcription. All eukaryotic cells have five major classes of RNA: ribosomal RNA (rrna), messenger

More information

Biotechnology Unit 3: DNA to Proteins. From DNA to RNA

Biotechnology Unit 3: DNA to Proteins. From DNA to RNA From DNA to RNA Biotechnology Unit 3: DNA to Proteins I. After the discovery of the structure of DNA, the major question remaining was how does the stored in the 4 letter code of DNA direct the and of

More information

CELL BIOLOGY - CLUTCH CH. 7 - GENE EXPRESSION.

CELL BIOLOGY - CLUTCH CH. 7 - GENE EXPRESSION. !! www.clutchprep.com CONCEPT: CONTROL OF GENE EXPRESSION BASICS Gene expression is the process through which cells selectively to express some genes and not others Every cell in an organism is a clone

More information

The Genetic Code and Transcription. Chapter 12 Honors Genetics Ms. Susan Chabot

The Genetic Code and Transcription. Chapter 12 Honors Genetics Ms. Susan Chabot The Genetic Code and Transcription Chapter 12 Honors Genetics Ms. Susan Chabot TRANSCRIPTION Copy SAME language DNA to RNA Nucleic Acid to Nucleic Acid TRANSLATION Copy DIFFERENT language RNA to Amino

More information

Name. Student ID. Midterm 2, Biology 2020, Kropf 2004

Name. Student ID. Midterm 2, Biology 2020, Kropf 2004 Midterm 2, Biology 2020, Kropf 2004 1 1. RNA vs DNA (5 pts) The table below compares DNA and RNA. Fill in the open boxes, being complete and specific Compare: DNA RNA Pyrimidines C,T C,U Purines 3-D structure

More information

Lesson 1 Introduction to Genetic Engineering

Lesson 1 Introduction to Genetic Engineering Lesson 1 Introduction to Genetic Engineering Genetic engineering is the manipulation of an organism s genetic material (DNA) by introducing or eliminating specific genes A gene is a piece of DNA which

More information

The Major Function Of Rna Is To Carry Out The Genetic Instructions For Protein Synthesis

The Major Function Of Rna Is To Carry Out The Genetic Instructions For Protein Synthesis The Major Function Of Rna Is To Carry Out The Genetic Instructions For Protein Synthesis For example, protein synthesis in human mitochondria relies on a genetic code that Leder and Nirenberg were able

More information

Unit 6 DNA ppt 3 Gene Expression and Mutations Chapter 8.6 & 8.7 pg

Unit 6 DNA ppt 3 Gene Expression and Mutations Chapter 8.6 & 8.7 pg Unit 6 DNA ppt 3 Gene Expression and Mutations Chapter 8.6 & 8.7 pg 248-255 Which genes are transcribed on the chromosomes are carefully regulated at many points. Watch this! https://www.youtube.com/watch?v=oewozs_jtgk

More information

Molecular Cell Biology - Problem Drill 01: Introduction to Molecular Cell Biology

Molecular Cell Biology - Problem Drill 01: Introduction to Molecular Cell Biology Molecular Cell Biology - Problem Drill 01: Introduction to Molecular Cell Biology Question No. 1 of 10 1. Which statement describes how an organism is organized from most simple to most complex? Question

More information

MCB 102 University of California, Berkeley August 11 13, Problem Set 8

MCB 102 University of California, Berkeley August 11 13, Problem Set 8 MCB 102 University of California, Berkeley August 11 13, 2009 Isabelle Philipp Handout Problem Set 8 The answer key will be posted by Tuesday August 11. Try to solve the problem sets always first without

More information

Unit 7. Genetic Regulation, Development, and Biotechnology. AP Biology

Unit 7. Genetic Regulation, Development, and Biotechnology. AP Biology Unit 7 Genetic Regulation, Development, and Biotechnology The BIG Questions How are genes turned on & off in eukaryotes and prokaryotes? How do cells with the same genes differentiate to perform completely

More information

Differential Gene Expression

Differential Gene Expression Biology 4361 Developmental Biology Differential Gene Expression September 28, 2006 Chromatin Structure ~140 bp ~60 bp Transcriptional Regulation: 1. Packing prevents access CH 3 2. Acetylation ( C O )

More information

Control of Eukaryotic Genes. AP Biology

Control of Eukaryotic Genes. AP Biology Control of Eukaryotic Genes The BIG Questions How are genes turned on & off in eukaryotes? How do cells with the same genes differentiate to perform completely different, specialized functions? Evolution

More information

Division Ave. High School AP Biology

Division Ave. High School AP Biology Control of Eukaryotic Genes 2007-2008 The BIG Questions n How are genes turned on & off in eukaryotes? n How do cells with the same genes differentiate to perform completely different, specialized functions?

More information

(A) Extrachromosomal DNA (B) RNA found in bacterial cells (C) Is part of the bacterial chromosome (D) Is part of the eukaryote chromosome

(A) Extrachromosomal DNA (B) RNA found in bacterial cells (C) Is part of the bacterial chromosome (D) Is part of the eukaryote chromosome Microbiology - Problem Drill 07: Microbial Genetics and Biotechnology No. 1 of 10 1. A plasmid is? (A) Extrachromosomal DNA (B) RNA found in bacterial cells (C) Is part of the bacterial chromosome (D)

More information

Genome Architecture Structural Subdivisons

Genome Architecture Structural Subdivisons Lecture 4 Hierarchical Organization of the Genome by John R. Finnerty Genome Architecture Structural Subdivisons 1. Nucleotide : monomer building block of DNA 2. DNA : polymer string of nucleotides 3.

More information

Problem Set 8. Answer Key

Problem Set 8. Answer Key MCB 102 University of California, Berkeley August 11, 2009 Isabelle Philipp Online Document Problem Set 8 Answer Key 1. The Genetic Code (a) Are all amino acids encoded by the same number of codons? no

More information

Chapter 8: DNA and RNA

Chapter 8: DNA and RNA Chapter 8: DNA and RNA Lecture Outline Enger, E. D., Ross, F. C., & Bailey, D. B. (2012). Concepts in biology (14th ed.). New York: McGraw- Hill. 1 8-1 DNA and the Importance of Proteins Proteins play

More information

STSs and ESTs. Sequence-Tagged Site: short, unique sequence Expressed Sequence Tag: short, unique sequence from a coding region

STSs and ESTs. Sequence-Tagged Site: short, unique sequence Expressed Sequence Tag: short, unique sequence from a coding region STSs and ESTs Sequence-Tagged Site: short, unique sequence Expressed Sequence Tag: short, unique sequence from a coding region 1991: 609 ESTs [Adams et al.] June 2000: 4.6 million in dbest Genome sequencing

More information

Molecular Genetics Techniques. BIT 220 Chapter 20

Molecular Genetics Techniques. BIT 220 Chapter 20 Molecular Genetics Techniques BIT 220 Chapter 20 What is Cloning? Recombinant DNA technologies 1. Producing Recombinant DNA molecule Incorporate gene of interest into plasmid (cloning vector) 2. Recombinant

More information

EUKARYOTIC GENE CONTROL

EUKARYOTIC GENE CONTROL EUKARYOTIC GENE CONTROL THE BIG QUESTIONS How are genes turned on and off? How do cells with the same DNA/ genes differentiate to perform completely different and specialized functions? GENE EXPRESSION

More information

13.1 RNA. Lesson Objectives. Lesson Summary

13.1 RNA. Lesson Objectives. Lesson Summary 13.1 RNA Lesson Objectives Contrast RNA and DNA. Explain the process of transcription. Lesson Summary The Role of RNA RNA (ribonucleic acid) is a nucleic acid like DNA. It consists of a long chain of nucleotides.

More information

BIOLOGY 101. CHAPTER 18: Gene Expression: Turning genes on and off

BIOLOGY 101. CHAPTER 18: Gene Expression: Turning genes on and off BIOLOGY 101 CHAPTER 18: Gene Expression: Turning genes on and off BACTERIAL TRANSFORMATION: Bacteria have the ability to pick up DNA from their surroundings and transcribe it as if it was their own. When

More information