chapter 13 part 1

Question 1

activator proteins bind regulatory sequences to ___________ transcription

Answer 1

stimulate

Question 2

repressor proteins bind other sequences to __________ transcription

Answer 2

hinder

Question 3

difference of cis elements in simple and complex euk

Answer 3

• simple: single binding sites, located close to 5’ end
• complex: multiple binding sites, located at varied distances

Question 4

3 regulatory DNA sequences

Answer 4

1. core promoter region
2. proximal elements
3. enhancer/silencer sequences

Question 5

where is the TATA box

Answer 5

core promoter region

Question 6

what does the core promoter region bind

Answer 6

RNA polymerase II and its associated general transcription factors

Question 7

where are proximal elements located

Answer 7

upstream of the core promoter region

Question 8

where do enhancer/silencer sequences act from

Answer 8

greater distances from the core promoter
- upstream, downstream, close to, very far, or within the genes they regulate

Question 9

all 3 regulatory regions are ______-acting regulatory sequences

Answer 9

cis

Question 10

RNA pol II and various GTFs are _______-acting regulatory proteins

Answer 10

trans

Question 11

enhanceosomes

Answer 11

aggregations of multiple proteins that form at enhancers

Question 12

what do enhanceosomes direct

Answer 12

DNA bending/loop formation

Question 13

what does DNA bending/loop formation allow

Answer 13

enhance-some proteins to interact with RNA polymerase and transcription factors at the core promoter and proximal promoter elements

Question 14

enhancer activity typically helps control what?

Answer 14

timing and location of gene transcription

Question 15

enhancers and silencers both contain what?

Answer 15

binding sites (modules) for several transcription factors

Question 16

what do the modules on enhancers and silencers allow

Answer 16

integration of activities of different transcription factors to produce different outputs

Question 17

pioneer factors

Answer 17

first to bind regulatory molecules, facilitating binding of additional transcription factors

Question 18

true or false: the same sequence can act as an enhancer or silencer, depending one which regulatory proteins are present

Answer 18

true

Question 19

what does the Sonic Hedgehog gene code for in humans

Answer 19

limb formation

Question 20

what is the SHH gene controlled by

Answer 20

enhancer 1 million base pairs away from the SHH gene

Question 21

how is SHH expressed

Answer 21

tissue-specific fashion due to action of 2 different enhancers

Question 22

2 different enhancers for SHH gene

Answer 22

• brain tissue
• developing limbs

Question 23

locus control region

Answer 23

highly specialized enhancer that regulates transcription of multiple genes packaged into complexes of closely related genes