3.13: Gene Control: Regulating protein production (HW check !)

Slides:

Advertisements

Similar presentations

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.

Advertisements

Control of Expression In Bacteria –Part 1

Definitions Gene – sequence of DNA that is expressed as a protein (exon) Genes are coded –DNA →RNA→Protein→Trait Transcription – rewritting DNA into RNA.

Section 12 – 5 Gene Regulation

Control of Prokaryotic Gene Expression. Prokaryotic Regulation of Genes Regulating Biochemical Pathway for Tryptophan Synthesis. 1.Produce something that.

12-5 Gene Regulation.

AP Biology Chapter 18: Gene Regulation. Regulation of Gene Expression Important for cellular control and differentiation. Understanding “expression” is.

G ENE R EGULATION The turning on and off of genes Allows organisms to respond to environmental changes Ex: lac Operon in bacteria.

Operons. Big picture Prokaryotic control of genome expression Prokaryotic control of genome expression 2 levels of control 2 levels of control  Change.

OPERONS: BACTERIAL GENE CONTROL. OPERONS Bacterial cells A group of genes that work together Illustrate how genes expression (“on”) and repression (“off”)

Four of the many different types of human cells: They all share the same genome. What makes them different?

REGULATION of GENE EXPRESSION. GENE EXPRESSION all cells in one organism contain same DNA every cell has same genotype phenotypes differ skin cells have.

Gene regulation  Two types of genes: 1)Structural genes – encode specific proteins 2)Regulatory genes – control the level of activity of structural genes.

Activate Prior Knowledge

Gene Control Chapter 11. Prokaryotic Gene Regulation Operons, specific sets of clustered genes, are the controlling unit Promoter: sequence where RNA.

Chapter 11 Table of Contents Section 1 Control of Gene Expression

Draw 8 boxes on your paper

Gene Expression Cells use information in genes to build hundreds of different proteins, each with a specific function. But, not all proteins are required.

Gene Expression and Regulation

Gene Control: Regulating how much of a protein gets made Complicated systems usually have parts that control what happens and how fast it happens. Do Now:

1 Gene regulation in Prokaryotes Bacteria were models for working out the basic mechanisms, but eukaryotes are different. Some genes are constitutive,

Control Mechanisms. Four Levels of Control of Gene Expression Type of ControlDescription Transcriptional Regulates which genes are transcribed. Controls.

GENETICS UNIT FIVE DAY 1. OPENER If you did your Spring Break Genetics Review HW, take it out and raise your hand in the NEXT 30 SECONDS.

Section 2 CHAPTER 10. PROTEIN SYNTHESIS IN PROKARYOTES Both prokaryotic and eukaryotic cells are able to regulate which genes are expressed and which.

1 Gene Regulation Organisms have lots of genetic information, but they don’t necessarily want to use all of it (or use it fully) at one particular time.

How Does A Cell Know? Which Gene To Express Which Gene To Express& Which Gene Should Stay Silent? Which Gene Should Stay Silent?

Gene Control: Regulating how much of a protein gets made Complicated systems usually have parts that control what happens and how fast it happens. Do Now:

Gene Expression. Remember, every cell in your body contains the exact same DNA… …so why does a muscle cell have different structure and function than.

Gene Expression and Regulation

Prokaryotic cells turn genes on and off by controlling transcription.

Complexities of Gene Expression Cells have regulated, complex systems –Not all genes are expressed in every cell –Many genes are not expressed all of.

AP Biology April 12, 2012 BellRinger Quiz  Identify and describe the 3 main parts of an operon Objective  Explain prokaryotic and eukaryotic gene regulation.

Controlling Gene Expression. Control Mechanisms Determine when to make more proteins and when to stop making more Cell has mechanisms to control transcription.

GENE EXPRESSION and the LAC OPERON We have about genes inside our DNA that code for proteins. Clearly not all the proteins are needed at the same.

Genes in ActionSection 2 Section 2: Regulating Gene Expression Preview Bellringer Key Ideas Complexities of Gene Regulation Gene Regulation in Prokaryotes.

Gene Expression & Regulation Chapter 8.6. KEY CONCEPT Gene expression is carefully regulated in both prokaryotic and eukaryotic cells.

Warm Up Write down 5 times it would be beneficial for a gene to be ‘turned off’ and the protein not be expressed 1.

Gene Structure and Regulation. Gene Expression The expression of genetic information is one of the fundamental activities of all cells. Instruction stored.

6D – Recognize that a gene expression is a regulated process.

Operons In E. coli, all 5 genes that code for the production of the enzymes that make tryptophan (when necessary) are all located together Benefit: A single.

OPERONS * Indicated slides borrowed from: Kim Foglia

Control of Gene Expression

6D – Recognize that a gene expression is a regulated process.

How does your body know when to make proteins?

Control of Prokaryotic (Bacterial) Genes

Gene Regulation.

Prokaryotic cells turn genes on and off by controlling transcription.

Prokaryotic cells turn genes on and off by controlling transcription.

Regulation of Gene Expression

Daily Warm-Up Tuesday, Jan. 7th

Chapter 12.5 Gene Regulation.

Control of Prokaryotic (Bacterial) Genes

The Operon Hypothesis The Operon Hypothesis was developed by 2 researchers: Jacob and Monod It explains how genes are regulated in prokaryotes. They received.

Agenda 3/16 Genes Expression Warm Up Prokaryotic Control Lecture

Regulation of Protein Synthesis

Control Mechanisms.

Prokaryotic cells turn genes on and off by controlling transcription.

Control of Prokaryotic (Bacterial) Genes Different from Eukaryotes!

Gene Expression Activation of a gene to transcribe DNA into RNA.

Regulation of Gene Expression

Prokaryotic cells turn genes on and off by controlling transcription.

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.

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.

Prokaryotic (Bacterial) Gene Regulation

Prokaryotic cells turn genes on and off by controlling transcription.

Prokaryotic cells turn genes on and off by controlling transcription.

Gene Regulation A gene (DNA) is expressed when it is made into a functional product (protein/enzyme)

Prokaryotic cells turn genes on and off by controlling transcription.

Presentation transcript:

3.13: Gene Control: Regulating protein production (HW check 10.15-16!) Objectives: 1. define operon, promoter, repression, repressor, induction, and inducer. 2. explain how the presence of an inducer turns on the transcription of lac genes in E. coli. TASK: 2. What might happen to a cell if it produced lots of protein that it didn’t need? Why might overproduction be a problem? Waste of ENERGY & Amino Acids

System Controls Each of these “faders” controls the volume of one audio track. Some can be programmed to move up and down as the song changes from part to part. The different colors of each square represent the “volume” of one gene. As a cell grows, matures, and changes, it produces proteins at different rates.

The lac Operon By E. coli The problem: Lactose is a type of sugar (found in milk) that can be metabolized for energy, just like glucose. Only cells that produce the lactase enzyme can utilize lactose as a source of energy. If there’s no lactose around, making the proteins needed to transport lactose and break it down is a BIG waste of resources. Did You Know??? Over 95% of Native American Indians and Asia-Pacific Islanders cannot digest lactose Over 95% of Northern European populations can. Which civilization hunted meat? Which one raised goats and cows?

Operons An operon is a gene plus the control mechanisms associated with it. Genes begin with a promoter, which is where RNA polymerase attaches to begin transcription. Many operons include an operator, which controls whether a gene will be repressed (off) or induced (on)

The lac operon Regulates Gene Expression lac operon structure INDUCTION : ON REPRESSION : OFF No Lactose Lactose

lac Operon diagrams Color each part of the system the same color every place it appears. If you finish before we move on, begin working on the worksheet on the back.

Lac Operon Animations Lacfinal_redone2.avi LacOperon QT As you watch, compare what you see in the two different animations – Hint: check out the repressor protein.

Lac operon: The Big Ideas The ability to control gene expression is vital to living cells. Without it, cells could not adapt to any changes in their environment. Proteins, DNA, and RNA molecules interact with each other to control gene expression. The lac operon is one example of such a control system Repressed genes are not expressed, induced / activated genes are expressed.

Splicing (mRNA processing) mRNA splicing does not occur regularly in prokaryotes. Just one more reason they’re easier to work with! After transcription in eukaryotes, most mRNA molecules get processed before they can be used to direct protein synthesis

mRNA Splicing During this process, introns are removed, and exons are joined together. If parts of the sequence are combined in different ways, one gene can actually produce several different proteins It’s a complex process

Homework Finish Worksheet if you have not Reading on syllabus is suggested. Papers due tomorrow! Hard copy preferred Email by 3:05. If emailing, submit prewriting & rubric in class. Nijato@gmail.com

Closing Thought Genes are controlled by the complex interactions of DNA, RNA, and proteins.