Exam 3 review

Question 1

What are the three ways in which RNA polymerase “scans” the bacterial genome?

Answer 1

Sliding, Intersegmental transfer, and Intrasegmental transfer

Question 2

Mutations in sigma factor’s DNA binding domain are unlikely to change its affinity for hexameric promoter elements.

Answer 2

False

Question 3

During abortive initiation nascent RNA approximately ________ long is synthesized and the RNA polymerase holoenzyme ________ change locations.

Answer 3

9 base; does not

Question 4

The positioning factor for RNA polymerase III is:

Answer 4

TFIIIB

Question 5

Which features define a transcription factor?

Answer 5

it must bind DNA in a sequence specific manner,it must be a protein, and it must participate in transcriptional regulation

Question 6

During transcriptional initiation a ternary complex is formed comprising of:

Answer 6

RNA polymerase holoenzyme, nascent RNA, and template DNA

Question 7

DNA repair and transcription can be coupled, which of the following factors participates in both DNA repair and transcription.

Answer 7

TFIIH

Question 8

An RNA polymerase III type 1 promoter contains which cis elements:

Answer 8

boxA, boxC

Question 9

Recognizing and binding to the translational start site is a function of __________.

Answer 9

the small ribosomal unit

Question 10

Translational elongation is a GTP dependent mechanism.

Answer 10

True

Question 11

Fusion of FokI to a TALE protein provides the nuclease activity in a TALEN

Answer 11

True

Question 12

How many different types of RNA polymerases can be found in E. coli?

Answer 12

1

Question 13

Enhancer elements are almost always upstream of the minimal promoter.

Answer 13

False

Question 14

Sigma factor binding to the core enzymes causes a conformational change that ________ the connection between the holoenzyme and the template strand.

Answer 14

increases

Question 15

Where does a formylated methionine-tRNAf enter the ribosome?

Answer 15

P-site

Question 16

A start point in a bacterial or eukaryotic promoter is almost always a (an) ______ ?

Answer 16

purine

Question 17

RNA polymerase I is primarily active in the ________.

Answer 17

nucleolus of a eukaryotic nucleus

Question 18

CpG islands in eukaryotic genomes may be the target of methylation. The result of CpG methylation in the promoter region of a structural gene will most likely ________________ .

Answer 18

inhibit transcription of a gene

Question 19

Fluorescently labeled chain terminating dideoxynucleotides are used in:

Answer 19

Sanger sequencing

Question 20

A rut site is a target for ________ binding?

Answer 20

Rho factor

Question 21

Dead Cas9 (dCas9) retains nuclease activity but cannot bind to target DNA.

Answer 21

False

Question 22

Which major cis element is consistently contained in an RNA polymerase II promoter?

Answer 22

Inr

Question 23

During promoter binding and initiation sigma factor physically interacts with the RNA polymerase core enzymes and the promoter sequence.

Answer 23

True

Question 24

Which mechanism for finding and removing “bad” mRNA takes its signal from the presence of a premature termination codon and an unusually lengthy 3’UTR?

Answer 24

nonsense mediated decay

Question 25

EF-Tu and EF-G can occupy the same A-site simultaneously.

Answer 25

False

Question 26

Sigma factor always disassociates from the holoenzyme enzymes before elongation can proceed.

Answer 26

False

Question 27

Which is true about a protospacer?

Answer 27

protospacer represents a target sequence in the CRISPR system

Question 28

In E. coli RNA polymerase is most often found associated with DNA.

Answer 28

True

Question 29

Deoxyribonucleoside triphosphates are required for RNA synthesis.

Answer 29

False

Question 30

Partner proteins in transcription may or may not transcription factors.

Answer 30

True

Question 31

TBP must bind the TATA-box

Answer 31

False

Question 32

Intrinsic termination relies on cis acting factors.

Answer 32

True

Question 33

Which cis elements comprise a bacterial promoter?

Answer 33

Pribnow box and -35 box

Question 34

The simplest and most cost-effective method for detecting the presence or absence of a specific DNA sequence is quantitative Realtime PCR.

Answer 34

False

Question 35

Where does an aminoacyl-tRNA enter the ribosome?

Answer 35

A-site

Question 36

What are the two primary mechanisms for transcriptional termination in prokaryotes?

Answer 36

Rho dependent termination and Intrinsic termination

Question 37

A gene drive only moderately increases the inheritance of the selfish allele above typical Mendelian pattern of inheritance.

Answer 37

False

Question 38

The terminator sequence that instructs bacterial RNA polymerase to cease transcription is only part of the DNA template sequence.

Answer 38

False

Question 39

The bacterial RNA polymerase holoenzyme is a complex of:

Answer 39

α2ββ'ωσ

Question 40

In eukaryotes, RNA polymerase is responsible for locating and binding to the core promoter without aid from other factors.

Answer 40

False

Question 41

In transcription, assembly factors are directly responsible for _________ .

Answer 41

positioning the positioning factors at the promoter

Question 42

Enhancer elements are always required for RNA polymerase II transcription.

Answer 42

False

Question 43

CRISPR is an acronym for...

Answer 43

clustered regularly interspaced short palindromic repeat

Question 44

Using Cas9 nickase (nCas9) can improve genome editing specificity by requiring a second Cas9 target for DNA double strand cleavage.

Answer 44

True

Question 45

Nonsense mediated decay can be bypassed by artificial addition of a PABP site immediately downstream of the premature termination codon.

Answer 45

True

Question 46

In genome editing an off-target effect is a consequence of editing the wrong sequence.

Answer 46

True

Question 47

What protein is part of all positioning factors?

Answer 47

TATA binding protein

Question 48

In a mammalian cell, what proportion of total RNA is ribosomal RNA (rRNA)?

Answer 48

70%

Question 49

An RNA polymerase III type 3 promoter contains which cis elements:

Answer 49

PSE, Oct, TATA-box

Question 50

What would one expect if the NTD (N-terminal domain) of σ70 is deleted in a bacterium?

Answer 50

σ70 would stick to DNA even in the absence of the RNA polymerase core enzyme.

Question 51

Sigma factor is required for transcriptional initiation but not elongation.

Answer 51

True