Eukaryotic Gene Regulation

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• Biology
• Secondary Education

Unit 3: Genetics

Module: Molecular Genetics

Lesson 4: Gene Regulation and Mutation

Focus Question: How do prokaryotes and eukaryotes regulate their genes?

Learning Outcomes

By the end of this lesson, you will be able to,

• Relate cell differentiation to gene expression regulation – Hox Genes

• Evaluate role of RNA interference in regulating eukaryotic gene expression

• To start transcription, transcription factors,  must first bind to the promoter and recruit RNA polymerase to that location.

• In addition to promoter sequences, enhancer regions help speed up transcription.

• Transcription factors bind to enhancer regions to increase or prevent transcription.

Recap:

What is the role of transcription factors in gene regulation?

1. Transcription factors only regulate gene expression in plants

2. Transcription factors are only present in non-coding regions of DNA

3. Transcription factors are not involved in gene regulation

4. Transcription factors bind to DNA and regulate the transcription of genes.

Give an example of a regulatory protein.

1. Ribosome kinase

2. Transcription factor

3. RNA polymerase

4. DNA helicase

Most gene regulation happens at which step along the way?

1. translation

2. transcription

3. signal transduction

4. DNA replication

___ are DNA sequences which are often located far from the genes they regulate in eukaryotes where transcription activators can bind.

1. histones

2. promotors

3. enhancers

In eukaryotes, proteins that help the RNA polymerase bind to the regulatory region for transcription are called ____________.

1. transcription factors

2. topoisomerase

3. regulatory genes

4. Activators

In eukaryotic cells, transcription cannot begin until 

1. the two DNA strands have completely separated and exposed the promoter.

2. several transcription factors have bound to the promoter.

3. the 5' caps are removed from the mRNA.

4. the DNA introns are removed from the template.

What is the primary function of transcription factors in gene regulation?

1. To splice RNA

2. To methylate DNA

3. To initiate or block the transcription of specific genes

4. To degrade mRNA

Which of the following best describes the function of enhancers in gene regulation?

1. They are DNA sequences that enhance the stability of mRNA

2. They bind to transcription factors to degrade mRNA

3. They are DNA sequences that increase the rate of transcription of associated genes

4. They modify histones to prevent transcription

One way to regulate the expression of a gene is to control the formation of mRNA. This is called ___ control.

1. transcriptional

2. translational

3. post-transcriptional

4. post-translational

Eukaryotic Gene Regulation

Hox Genes

• Gene regulation is crucial during development and cell differentiation.

• One group of genes that control cell differentiation is the homeobox (Hox) gene group.

• Hox genes are transcribed at specific times in specific places on the genome.

• Hox genes control which body part will develop at a given body location.

Eukaryotic Gene Regulation

Hox Genes

Hox genes are responsible for the general body pattern of most animals. Notice that the order of the genes is the same as the order of the body sections the genes control.

Translational Control

RNA Interference

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Discuss your Understanding

RNA Interference

Summary

Summarization

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