Control of Gene Expression

Question 1

__________ refers to the way that groups of regulatory proteins work together to determine the expression of a single gene. (pg 280)

Answer 1

Combinatorial Control

Question 2

How does the same DNA result in such different cells, as seen in a lymphocyte, a hepatocyte, and a neuron?

Answer 2

Gene expression

Question 3

Where does the principle control of tissue specific expression reside?

Answer 3

Transcriptional Control

Question 4

_______ ___ _______ are used to switch the gene on or off. (pg 273)

Answer 4

Regulatory DNA Sequences

Question 5

Regulatory DNA sequences do not work by themselves. These sequences must be recognized by proteins called _______ _______, which bind to regulatory DNA sequences in the promoter (pg 273).

OR DNA binding proteins regulating transcription.

Answer 5

Transcription Factors

Question 6

Transcription factors fit into the _____ ______ of the DNA double helix and form tight associations with a short stretch of DNA base pairs.

Answer 6

Major Groove

Question 7

Amino acid R groups contact 10-20 ____ _____ _____.

Answer 7

Nucleic acid bases

Question 8

Hydrogen, Ionic, and _______ bonds are involved. Hydrogen bonds between bases are weak.

Answer 8

Hydrophobic

Question 9

________ are the gene regions that regulate expression.

Answer 9

Promoters

Question 10

In prokaryotes, genes directing the steps in a process are often organized into clusters, or _________, that are transcribed together into a single mRNA. (pg 256)

Answer 10

Operons

Question 11

Prokaryotic mRNAs are often ____________, which means they encode several different proteins, each of which is translated from the same mRNA molecule

Answer 11

Polycistronic

Question 12

The encoded proteins are often involved in a single metabolic function/pathway and need to be ________ _______ (hint: multiple genes controlled together in a coordinated way).

Answer 12

coordinately expressed

Question 13

What happens when tryptophan binds to the active repressor on the promoter site?

Answer 13

RNA polymerase can’t bind and the genes are turned off

Question 14

Tryptophan and the active repressor directly inhibit transcription by _______ ________ of RNA polymerase.

Answer 14

Steric hindrance

Question 15

This protein binds to the promoter, but doesn’t inhibit RNA polymerase. It activates it through _______ _______.

Answer 15

Positive stimulation

Question 16

A synthesis and processing complex providing subtle control and efficient expression allowing integration of multiple signals…

Answer 16

A combinatorial complex

Question 17

Enhancers bound by _______ _________ _______ regulate expression in Eukaryotes.

Answer 17

enhancer binding proteins

Question 18

________ encode tissue-specific gene expression.

Answer 18

Enhancers

Question 19

The ______ is the protein that combines the combinatorial complex and the enhancer.

Answer 19

Mediator

Question 20

_____ and _____ signals compete for influence over the promoter.

Answer 20

Poistive; repressive

Question 21

Signals must be integrated into a ______ output of yes or no for transcription.

Answer 21

Simple