Kandpal - Transcription

Question 1

What are the structural differences between RNA and DNA?

Answer 1

RNA is mostly single stranded, ribose, uracil

DNA is double stranded, deoxyribose, thymine

Question 2

List the different RNAs from least abundant to most.

Answer 2

mRNA, tRNA, and rRNA

Question 3

List 4 functions of RNA.

Answer 3

Genome, information carrier, protein synthesis, and as a catalyst.

Question 4

What is an example of RNA as a genome?

Answer 4

HIV virus

Question 5

How is RNA involved in protein synthesis?

Answer 5

As rRNA and tRNA

Question 6

Name an example of a catalytic RNA.

Answer 6

peptidyl transferase

Question 7

What carbon is different between ribose and deoxyribose?

Answer 7

2’ carbon

Question 8

Where is mRNA located?

Answer 8

nucleus and cytoplasm

Question 9

Where is tRNA located?

Answer 9

cytoplasm

Question 10

Where is rRNA located?

Answer 10

ribozymes and nucleus

Question 11

How many subunits does RNA polymerase in E. coli have?

Answer 11

5 subunits

Question 12

What part of the RNA polymerase recognizes the promoter sequence?

Answer 12

the sigma subunit recognizes the promoter sequence

Question 13

What does tight binding of the promoter with the promoter sequence lead to?

Answer 13

opening of the DNA

Question 14

What is strength of binding and speed of binding dependent on?

Answer 14

It is dependent on the promoter sequence

Question 15

What occurs if the promoter sequence is closely related to the sigma subunit?

Answer 15

The bond forms faster and it is a stronger/tighter bond

Question 16

What are known as consensus sequences?

Answer 16

the short conserved sequences of the promoter sequence

Question 17

What is the -35 consensus sequence?

Answer 17

35 bases upstream of the start site; varies from 16-19 base pairs

Question 18

What is the -10 consensus sequence?

Answer 18

10 bases upstream of the start point; varies from 5-9 base pairs

Question 19

What is the starting point referred to?

Answer 19

+1

Question 20

How many RNA polymerases do eukaryotes have and how many do bacteria have?

Answer 20

Eukaryotes have 3 and bacteria only has one.

Question 21

How does eukaryotic RNA polymerase bind to promoter?

Answer 21

Binds indirectly by contacting promoter sequences via transcription factors

Question 22

Between eukaryotes and bacteria which uses operons?

Answer 22

bacteria

Question 23

Which genes are individually regulated bacteria or eukaryotic?

Answer 23

Eukaryotic

Question 24

Which bacterial polymerase directly binds the promoter sequence?

Answer 24

the bacterial RNA polymerase holoenzyme that contains the sigma subunit

Question 25

How can bacterial and eukaryotic RNA polymerases be distinguished?

Answer 25

By their susceptibilities to two inhibitors: rifampin (bacterial) and alpha-amanitin (eukaryotic)

Question 26

How does rifampin inhibit bacterial RNA polymerase?

Answer 26

it binds to the beta subunit and blocks the path of nascent RNA

Question 27

How does alpha-amanitin inhibit eukaryotic RNA polymerase?

Answer 27

binds to and inactivates the largest subunit of RNA polymerase II, RPB1

Question 28

What blocks transcription in both bacterial and eukaryotic polymerases?

Answer 28

actinomycin-D prevents transcription in both by binding to DNA

Question 29

What kind of antibiotic is Rifampicin?

Answer 29

broad-spectrum antibiotic used for mycobacterial infections (pts w/TB and immunosuppressed pts)

Question 30

What is a point of concern with rifampicin antibiotics?

Answer 30

point mutation in bacterial beta subunit changes rifampin binding site and does not allow it to bind

Question 31

What type of antibiotic is Ciprofloxacin?

Answer 31

A quinolone antibiotic

Question 32

How does quinolone work?

Answer 32

binds to the A subunit of bacterial DNA gyrase and impairs DNA cleavage and resealing activity = DNA damage

Question 33

What type of antibiotic is Novobiocin?

Answer 33

A coumarin antibiotic

Question 34

How does Novobiocin work?

Answer 34

inhibits bacterial DNA gyrase by binding to the ATP binding site of the B subunit = inhibition DNA supercoiling (transcription of genes is disrupted)