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Flashcards in Regulation of Transcription Deck (48):
1

four types of DNA binding regulatory proteins

helix turn helix
zinc fingers
leucine zippers
helix loop helix

2

these proteins regulate genes involved in development

helix turn helix

3

these proteins are steroid hormone receptors

zinc finger motif

4

these proteins regulate cell division genes

leucine zipper

5

these proteins regulate immune system genes

helix loop helix

6

examples of DNA binding domains

homeodomains

7

how do DNA binding domains interact with the major groove of DNA

H-bonds
salt-bridges
hydrophobic interactions

8

two characteristics of DNA binding domains

rich in alpha helices
can bind to promoters and enhancer sequences

9

have an acidic patch that allows interaction with other transcription factors

activation domain

10

what can activation domains bind to

other transcription factors
RNA polymerase II
activators

11

genes are not transcribed unless an activator is present

positive control

12

positive control that turns genes on

activation

13

positive control that turns genes off

deactivation

14

genes are always transcribed unless a repressor is present

negative control

15

negative control that turns genes off

repression

16

negative control that turns genes on

derepression

17

a unit of genetic function consisting of groups of genes with related functions where a single promoter and operator serve to control the expression of all genes in that unit together

operons

18

where to operons primarily occur

in prokaryotes and nematodes

19

an inducible operon where transcription is stimulated in the presence of lactose

lac operon

20

a repressible operon where transcription is inhibited in the presence of tryptophan

trp operon

21

lactose is made up of

galactose and glucose

22

what form of lactose binds to the lac operon repressor

allolactose

23

regulatory genes for the lac operon code for

repressor protein
CAP

24

the lac repressor exhibits what kind of motif

helix turn helix

25

what three enzymes are coded for in the lac operon

Beta-galactosidase
permease
transacetylase

26

in conjuction with cAMP, serves as an indicator of glucose availability

CAP

27

when there is no glucose and there is lactose

increase in cAMP and binding to CAP
50x increase in transcription of lac genes

28

when there is glucose and lactose present

decreased cAMP and no binding to CAP
weak transcription

29

when there is glucose and no lactose present

decreased cAMP and no binding to CAP
lac repressor present and no transcription

30

how is trp operon different from lac operon

the presence of tryptophan causes the inhibition of the operon instead of its activation

31

affect the configuration of chromatin and gene expression

chemical modification of histone tails

32

how are histone tails modified

attachement of acetyl group to lysines

33

protein recruited to keep histones deacetylated

HDAC

34

activator protein binding recruits this protein which acetylates histones

HAT

35

histone modification that prevents transcription

methylation at lysines and arginines residues

36

what is the epigenetic regulation of histones in DNA

addition of methyl groups to cytosines of DNA

37

limits body weight and cell proliferation

H19

38

insulin like growth factor

IGF2

39

on the maternal chromosome and enhancer drives expression of ____ and an insulator protein blocks ____expression

H19 and IGF2

40

on paternal chromosome, methylation inactivates the ICR and block the ____ expression, enhancer drives ____expression

H19 and IGF2

41

if H19 is mutated or missing this disease develops

angelman syndrome

42

if IGF2 is mutated or missing this disease develops

prader-willi syndrome

43

what binds to the TATA box

transcription factors

44

what are close to the promoter

proximal control elements

45

may be far away from a gene or even in an intron

enhancers

46

what binds to enhancers

activators

47

bind to silencer region of the DNA to inhibit expression of a particular gene

repressors

48

describe the process of mRNA degradation

miRNA folds onto itself
dicer protein claves miRNA into smaller fragments
miRNA binds to protein complex
miRNA protein complex binds with mRNA
mRNA is degraded or translation is blocked