Module 4 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q
  • Sequence of genomic DNA or RNA that is
    essential for a specific function
  • Used to be defined as giving rise to an enzyme
A

Gene

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

(3) Types of Genes and functions

A
  1. protein-coding genes – TRANSLATED
  2. RNA-specifying genes – TRANSCRIBED ONLY
  3. untranscribed genes – do not get transcribed but affect the expression of other genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Type of mRNA as a transcription unit:

– contains 1 gene only
– common in eukaryotes

A

Monocistronic mRNA

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

Type of mRNA as a transcription unit:

  • contains several genes in tandem array
    – common in prokaryotes
A

Polycistronic mRNA

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

States that not all genes within a cell are active at the same time.

A

Regulation of Gene Expression

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

Stages where gene regulation occurs

A

*Transcription
*Post-transcription
*Translation
*Post-translation

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

In Transcriptional Regulation these are:

  • genes that are transcribed continuously

– not affected by the environment

A

Constitutive Genes

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

In Transcriptional Regulation these are:

genes governed by REGULATORY proteins

A

Non-constitutive genes

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

Types of regulatory proteins

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

Protein that prevents transcription

Binds to an OPERATOR sequence upstream of the gene in the
DNA

Negative control

A

Repressor

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

Protein that promotes transcription

Binds to either PROMOTER or ENHANCER sites in the DNA

Positive control

A

Activator

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

Sequences found at the 5’ flanking region of a gene

Signals initiation of transcription

A

Promoters

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

Promoter sequences in eukaryotes

A
  1. TATA Box – (TATAAA), Hogness-Goldberg box
  2. CAAT Box – (CAAT)
  3. GC Box – (GGGCGG)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Promoter in Eukaryotes found 19-27 bp upstream of start of transcription

A

TATA Box (TATAAA)

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

sequence that is translated

A

Exon

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

intervening sequence, eventually spliced off

A

intron

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

mRNA domains that control critical post-transcriptional gene regulation processes

untranslated

A

UTR (untranslated region)

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

Promoter sequences in prokaryotes

A

Pribnow Box (TATAAT)

TTGACA

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

Found 10 bp (technically 7 in the lab) from the start of transcription in prokaryotes

A

TATAAT

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

Found 35-bp upstream of start of transcription

A

TTGACA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  • unit of bacterial gene expression & regulation
  • Polycistronic
  • Contains regulatory elements
A

Operon

22
Q

Site to which RNA polymerase binds

A

Promoter

23
Q

Site to which repressor protein binds

A

Operator

24
Q

Structural Genes for lac operon:

A

Lac Z - beta-galactosidase
Lac Y - permease
Lac A - transacetylase

25
Q

Codes for repressor protein

A

Repressor

26
Q

T or F: In the absence of lactose, the repressor protein does not bind and transcription of structural
genes proceeds.

A

F: In the PRESENCE of lactose, the repressor protein does not bind and transcription of structural genes proceeds.

27
Q

T or F: In the absence of lactose, the repressor protein binds to the operator gene and blocks transcription.

A

T: In the absence of lactose, the repressor protein binds to the operator gene and blocks transcription.

28
Q

The lac operon is NEGATIVE INDUCIBLE CONTROL, why?

A

Negative control because of presence of repressor protein that prevents transcription; Inducible because it is based on the presence of lactose

29
Q

Structural genes of the trp operon.

A

*Trp E
*Trp D
*Trp C
*Trp B
*Trp A

30
Q

Regulates mRNA transcription

A

Attenuator

31
Q

T or F: In the absence of tryptophan, the repressor protein trpA-repressor can bind to the operator causing allosteric transition. The trp-Repressor complex binds to the operator and transcription is blocked.

A

F:In the absence of tryptophan, the repressor protein alone cannot bind to the operator. Transcription proceeds to form a Polycistronic mRNA. If tryptophan is present, the repressor protein, trpA-repressor, binds to tryptophan, causing allosteric transition. The trp-Repressor complex binds to the operator and transcription is blocked.

32
Q

The trp operon is under NEGATIVE REPRESSIBLE CONTROL, why?

A

Presence of tryptophan represses transcription of structural genes

Negative control because of presence of repressor that prevents transcription

33
Q

Regulator several hundreds or thousands of bp upstream or downstream of gene it regulates

A

Enhancer

34
Q

proteins encoded by separate
genes

bind to specific DNA sequences

also known as trans-acting
factors

A

Transcription Factors

35
Q

3 types of Transcription Factor DNA binding sites:

A
  1. Helix-turn-helix
  2. Zinc finger
  3. Leucine zipper
36
Q

immediate product of
transcription; edited before use or translation

A

pre-mRNA

37
Q

pre-mRNAs found in
nucleus of eukaryotes

A

hnRNA

38
Q

lends protection and stability to 5’ end; UNIQUE TO EUKARYOTES

A

5’ capping

39
Q

Addition of poly-A tail
to protect the 3’ end from exonucleases

A

3’ polyadenylation

40
Q

removal of introns

A

splicing

41
Q

In translation, prokaryote or eukaryote:

Formylmethionine as first amino acid

Shine-Dalgarno sequence – where 16S rRNA binds

AGGAGG 10 bases
upstream of AUG codon

A

Prokaryote

42
Q

In translation, prokaryote or eukaryote:

Methionine as first amino acid

7mGppp – where rRNA binds

A

Eukaryote

43
Q

Methods of Translational Regulation

A
  1. Altering the half-life or stability of mRNA for translation
  2. Controlling the initiation and rate of translation
  3. Regulation by microRNA (miRNA)
44
Q

removal of _______ reduces the half-life of mature mRNAs and decreasing their stability

A

poly-A binding protein (PABP)

45
Q

Small non-coding RNA molecule found in plants, animals, some viruses

Short, 19-23 nts in length

Encoded by eukaryotic nuclear gene (DNA)

Base pairs with complementary sites of mRNA in the cytoplasm; silences by prevention or delay of translation

Double or single stranded?

A

microRNA (miRNA); Double stranded

46
Q

Methods of Post-translational Regulation by Modification of protein product

A
  1. Ubiquitination
  2. Phosphorylation
  3. Glycosylation
  4. Enzymatic cleavage
47
Q

Post translational regulation where there is

attachment of protein ubiquitin to other
proteins

and

protein becomes target of destruction
by proteosome

A

Ubiquitination

48
Q

Post-translational regulation

carried out by kinases
by addition of phosphate group to amino acids affecting the activity of protein

A

Phosphorylation

49
Q

Post-translational regulation where there is

addition of carbohydrate group

also affects protein activity

A

Glycosylation

50
Q

Post-translational regulation where there is

breakdown of protein into smaller functional units carried out by PEPTIDASE

A

Enzymatic Cleavage

51
Q

Boss orig po ba yan? Bakit baliktad po, sabiba nakalagay?

A

Adik ka ba? >:0