2.15 Eukaryotic Transcription Control Flashcards Preview

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Flashcards in 2.15 Eukaryotic Transcription Control Deck (100)
1

View that genes cause trait

Genetic determinism

2

Reads DNA and tells you about your risk factors for certain diseases

DNA Test

3

Requirement for DNA Test

Saliva sample

4

RNAs synthesized by a cell or organism

Transcriptome

5

Set of protein sequences that can be derived by translation of all protein coding genes of a completely sequenced genome

Proteome

6

True or False
mRNA levels are not well-correlated with protein levels

True

7

Differentiation is anchored on ___

Gene expression

8

Study of changes in gene expression that are stable over rounds of cell division, and sometimes between generations but do not involve changes in the underlying DNA sequence of the organism

Epigenetics

9

Affects the phenotype of the organism

Epigenetics

10

Helps explain how environmental factors can impact gene expression, perhaps even after exposure to the original factor is over

Epigenetics

11

From double helix to chromosome
Gene has to be accessible for it to be transcribed

DNA Packaging

12

Difference between euchromatin (on) and heterochromatin (off)

Chromatin remodeling

13

Number of copies of a certain gene

Gene dosage

14

Important in expression

Gene dosing

15

In human cells, there are __ rDNA clusters located in ___. Each cluster contains ___ copies

5;
Chromosome 13, 14, 15, 21, 22;
-70

16

Leads to over expression of gene product

Gene amplification

17

Selective increase in number of a certain gene without affecting the quantity of the other genes

Gene amplification

18

Seen in multiple drug resistant genes, which code for pumps that eject molecules as drugs from the cell, and cancer cells

Gene amplification

19

Important for breast cancer

HER-2/neu (erbB-2, EGFR-2)

20

Monoclonal antibody that binds to Her-2 receptor

Herceptin

21

Prevents dimerization from happening

Herceptin

22

Transcription happens in ___ while translation happens in ___

Nucleus
Cytosol

23

RNA contains ___ in the C-2. This makes RNA more prone to hydrolysis

Hydroxyl group

24

3 regions of gene

Promoter
Coding Region
Termination sequence

25

Signals how much RNA/protein to produce and when and in which tissues

Promoter

26

Consensus promoter sequences in eukaryotes

TATA
CAAT

27

Composed of exons
Encodes the information for what protein to produce

Coding region

28

Signals the end of the gene

Termination sequence

29

Bind at promoter for the transcription initiation complex

SRB and RNA polymerase

30

Produced in the transcription

pre-mRNA

31

Done to protect and stabilize the primary transcripts as they exit into the cytosol

Posttranscriptional modifications

32

Posttranslational modifications

Capping 5' end
Attaching poly-A tail
Splicing introns

33

Binds the cap

Initiation factor

34

Searches for the start codon on the mRNA

eIFs
40s

35

RNA polymerase type I Location

Nucleus

36

RNA polymerase type I Cellular Transcripts

5.8s, 18s, 28s

37

RNA polymerase type I Effects of alpha-amanitin

Insensitive

38

RNA polymerase type II Location

Nucleoplasm

39

RNA polymerase type II Cellular Transcripts

mRNA precursors, snRNA, miRNA

40

RNA polymerase type I Effects of alpha-amanitin

Strongly inhibited

41

RNA polymerase type III Location

Nucleoplasm

42

RNA polymerase type III Cellular Transcripts

tRNA
5s
rRNA

43

RNA polymerase type III Effects of alpha-amanitin

Inhibited by high concentrations

44

Lies in DNA
Landing strip for RNA and general transcription factors

Promoters

45

Binding site of promoters are always in the ___ of the sequence

Beginning

46

Lies in DNA
Landing strip for specific transcription factors

Enhancers

47

Can be upstream, downstream or in the midst of a transcribed gene

Enhancers

48

Lies in DNA
Binds with transcription regulation factors

Silencers

49

Silencer-TRF complex prevents ___ from binding to promoter, hindering gene expression

RNA polymerase

50

Proteins
Bind to regulatory sites on DNA can be regarded as passwords that cooperatively open multiple locks, giving RNA polymerase access to specific gene

Transcription factors

51

Which genes will be transcribed

Localization of transcription factors

52

Stimulate transcription at start sites thousands of bases away

Enhancers

53

Enhancers increase effectiveness of ___

Promoters

54

Eukaryotic promoters

Multiple transcription factors

55

Composed of the basal/general transcription factors and RNA polymerase

Basal Transcription Apparatus

56

Transcription factor subunits are recruited in the following order to form the complex:

TFIIA, TFIIB, TFIIF, TFIIE

57

ATP-dependent helicase initially separates DNA duplex for the polymerase

TFIIF

58

Illustrates the modular nature of transcription factors

Pax6 (Paired box 6) TF

59

Illustrates many keys and multiple concept

Pax6 (Paired box 6) TF

60

Enhancer of the rat somatostatin gene

Pax6 (Paired box 6) TF
with Pdx1 TF

61

2 major promoters initiating transcription

Exon 0
Exon 1

62

Alternatively spliced exon

Exon 5a

63

Active in the pancreas

Enhancer A

64

Lens and cornea

Enhancer B

65

Neural tube

Enhancer C

66

Retina

Enhancer D

67

Within the DNA molecule
Can be located in a promoter or enhancer
Positions may vary but do not need to be next to the exons

Cis-acting elements

68

Diffusable elements
Not the sequences themselves but the products of the sequences

Trans-acting elements

69

Control gene expression by binding to cis-acting factors

Trans-acting elements

70

Importance of 5' cap

Stabilize mRNAs by protecting their ends from phosphatases and nucleases
Enhance translational of mRNAs by eukaryotic proteins
Protection and recognition

71

Importance of poly-A tail

Translation
Export to cytoplasm

72

mRNA is hydrolyzed downstream of the polyadenylation signal sequence to form pre-mRNA

Cleaving

73

Polyadenylation signal sequence

AAUAAA

74

Removes introns from RNA

Spliceosome

75

mRNA has to be transported from the nucleus to the cytosol through ____

Nuclear pore complex

76

3 general mechanisms for localization of mRNAs

mRNAs directed transport via cytoskeleton
Random diffusion and trapping
Generalized degradation + local protection

77

Function
mRNAs for actin

Cell movement and contraction

78

Function
mRNAs for tubulin

Mitotic spindles, cilia, flagella

79

Function
mRNAs for hypoxanthine phosphoribosyltransferase

Purine synthesis

80

Function
mRNAs for metalloproteinases

Implantation in uterus

81

Polarity of the bicoid signal is due to attachment of ___ to the cytoskeleton of the anterior region of egg

3' UTR

82

mRNA regulatory element that controls gene expression of bicoid protein

Bicoid 3' UTR regulatory element

83

Untranslated region
Indicates that there are still remaining mRNA

3'UTR

84

3' UTR is the target binding site of the ___

miRNAs

85

Regulates endogenous gene expression

RNAi

86

dsRNA cleaved by ___ into 21-25 nucleotide siRNA

Dicer

87

Mediates unwinding of siRNA

Slicer

88

siRNA forms complex with ___

RISC

89

Activates RISC

siRNA duplex

90

Cleaving mRNA

Gene silencing

91

(High/low) miRNA stops protein production

High

92

High lin-4RNA -> __ LIN-14

Low

93

High let-7 RNA -> __ LIN-41 protein

Low

94

Small RNAs that regulate gene expression
Repress translation by binding to or cleaving mRNA

miRNA

95

Does not need to be perfect binding, it can deal with multiple targets

Imperfect binding

96

Imperfect binding creates __

P-bodies

97

Complex that blocks translation

P-bodies

98

miRNA regulates degradation usually at the ___

3'UTRs

99

The 19-25nt miRNA;miRNA duplex is produced by ___

Dicer

100

True or false
Hormones can affect miRNA

True