Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MCBM Part 1 > Kandpal- Promoter, polymerases and transcription factors > Flashcards

Kandpal- Promoter, polymerases and transcription factors Flashcards

1
Q

what is the purpose of house keeping genes (constitutive)?

A

required for general cell functions and cell viability. usually used in basic metabolism and proteins for cell structures (ribosomes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the functions of regulated genes (inducible)?

A

cell-type specific genes which are responsible for the differentiated functions of specific cell typess. examples: hormone/growth, factor/stress responsive genes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

in eukaryotes what does gene regulation control?

A

growth, development, differentiation, cell to cell communication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

why is gene regulation important in prokaryotes?

A

adjustment of metabolic requirement in response to nutritional environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how is the synthetic pathway activated?

A

absense of the end product leads to activation of synthetic pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

when will trp synthesis begin?

A

in the absence of tryptophan

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what three things make up an operon?

A

protein coding genes, shared promoter and regulatory site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the role of lactose permease?

A

designated as Y (transport)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the role of beta-galactosidase-Z?

A

cleaves lactose into galactose and glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the role of galactoside transacetylase-A?

A

nonmetabolites removal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

in what genes can the enzymes permease, galactosidase and transacetylase be found?

A

found in the polycistronic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

when will the Lac repressor (tetrameric protein) occupy the operator of the Lac Operon?

A

in the absence of lactose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what else is inhibited when the lac repressor is bound to the Lac Operon?

A

binding of RNA polymerase to the promoter is excluded. Lactose metabolizing genes are not transcribed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

when will the affinity for the repressor be reduced for the operator?

A

in the presence of lactose (Lactose will bind to the repressor, which alters the repressors affinity for the operator)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

when E. coli was grown in a mixture of glucose and lactose, which substrate did the bacteria favor?

A

glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what effect does glucose have on lactose?

A

glucose represses lactose metabolizing enzymes and many other catabolic enzymes. this is known as “Catabolite Repression”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the levels of cAMP in the presence of glucose?

A

they are low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the function of cAMP?

A

needed for activation of DNA binding protein CAP and for transcription of ‘lac’ operon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the required criteria for the Lac Operon?

A

the Lac operon will be active if only lactose is present and glucose is absent (remember how glucose lowers cAMP levels)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what transcribes class 1 genes?

A

transcribed by RNA Polymerase 1.

rRNA (28S,18S, 5.8S)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what transcribes class 2 genes?

A

transcribed by RNA polymerase 2.

mRNA and U1 and U2 snRNA

22
Q

what transcribes class 3 genes?

A

transcribed by RNA polymerase 3.

tRNA, 5S rRNA and snRNA

23
Q

what are the three types of promoters?

A

TATA promoters, Initiator (Inr) promoters and TATA-less and initiator-less promoters

24
Q

where is TATA sequence located?

A

at 25 to 35

25
Q

what is an initiator pormoter?

A

a degenerate consensus sequence surrounding the start site of transcription

26
Q

what and where is the TATA-less and initiator-less promoters?

A

GC rich “island” approx 100 nucleotides upstream of the initiation start site

27
Q

what is the role of an enhancer?

A

DNA sequences usually containing several transcription factor binding sites that can activate transcription over long distances independently of their position and orientation relative to a gene.

28
Q

what is the role of a silencer?

A

similar to enhancers, but instead they repress transcription

29
Q

what properties does TFIIH have?

A

helicase and ATPase activity and CTD kinase activity

30
Q

what makes up TFIID?

A

TBP (TATA-Binding Protein) Complex

31
Q

what is the modular structure of activator proteins?

A

activator domain, DNA binding domain

32
Q

what does the activator domain communicate with?

A

communicates with TFs and Pol II via coactivators

33
Q

what do Homeobox proteins (products of homeotic genes) belong too?

A

helix-turn-helix class

34
Q

what is another name for homeotic genes?

A

Hox genes

35
Q

a mutation in what gene is responsible for polydactyly?

A

Hox gene

36
Q

people with VHL are susceptible to what?

A

growth of tumors in parts of the body (CNS, retina and kidney)

37
Q

what does VHL bind to and what does it control?

A

binds to subunits B and C of elongin (ubiquitan ligase complex). it controls the fromation of active elongin complex.

38
Q

what does elongin complex do?

A

elongin complex increases the rate of transcription elongation

39
Q

what does loss of VHL lead too?

A

activation of angiogenic pathway

40
Q

what does ubiquitin ligase complex lead too?

A

degradation of hypoxia inducible factor (HIF)

41
Q

what happens in VHL mutation?

A

prevented from binding to elongin BC and thus inhibit the formation of active ubiquitin ligase

42
Q

what is Pit-1

A

transcription factor for the transcription of growth hormone gene

43
Q

what is PROP-1?

A

a transcription factor for Pit-1. without it there will be no Pit-1 and therefore no growth hormone gene transcription

44
Q

what happens if you have a mutation in PROP-1 or Pit-1?

A

lead to GH deficiency

45
Q

what is huntingtons disease (HD)?

A

inherited neurodegenerative disease

46
Q

what happens to an individual with HD?

A

progressive deterioration of motor and cognitive abilities

47
Q

what type of genetic disease is HD?

A

autosomal dominant (chromosome 4).

48
Q

what kind of repeats are associated with HD?

A

expansion of CAG (glutamine) repeats

49
Q

why is glutamine expansion bad?

A

may interfere with transcription in neurons

50
Q

what transcription factor helps huntington protein to work?

A

Sp1 transcription factor (has a glutamine-rich activation domain)

51
Q

what receptor is affected by the mutant huntington protein?

A

dopamine (D2) receptor

MCBM Part 1 (29 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions