WEEK 5

Question 1

Gene

Answer 1

entire nucleic acid sequence (usually DNA) that is necessary for the synthesis of a protein (and its variants) or RNA. Genes are segments of DNA that are transcribed into RNA.

Question 2

Two types of genes that when transcribed…

Answer 2

one results in RNA that encodes for a protein and the second type results in RNA that functions as RNA.

Question 3

Where is the active site located in the RNA polymerase complex

Answer 3

closer to the front

Question 4

How is RNA polymerase similar to DNA polymerase? How is it different?

Answer 4

• RNAP also has a backspace function (exonuclease repair)

- doesn’t need a primer

Question 5

What is formed transiently during RNA transcription

Answer 5

a DNA RNA duplex

Question 6

Difference between DNA and RNA

Answer 6

DNA is missing the O of the hydroxyl group on its 2’ carbon

Question 7

What does the 5’ end of RNA have?

Answer 7

3 phosphate groups and then a sugar

Question 8

RNA is linked by… and is held to DNA with…

Answer 8

• phosphodiester bonds

- base pairing

Question 9

RNA polymerase relies on

Answer 9

base pairing and nucleoside triphosphates

- cuts off pyrophosphate when NTP joins 3’ OH to 5’ carbon

Question 10

Bacterial Transcription

Answer 10

1. Sigma factor binds to core enzyme and binds to promoter

2. Localized unwinding of DNA

Question 11

Holoenzyme

Answer 11

Sigma factor and RNAP core enzyme together

Question 12

Bacterial promoter

Answer 12

found at nucleotides -35 to -10 (where holoenzyme binds). The very first nucleotide that is transcribed is designated as +1.

Question 13

Abortive transcription

Answer 13

holoenzyme transcribes +1 to +10 multiple times and casts off RNA strands restarting. Sigma factor releases and RNAP enters processive mode.

Question 14

RNA termination

Answer 14

Reaches hairpin structure (also called a stem loop structure) followed by loose As and Us which pry polymerase off DNA.

Question 15

AUG

Answer 15

is the start of translation not transcription

Question 16

Which processes are coupled in prokaryotes but not in eukaryotes?

Answer 16

Transcription and translation - before RNA is done being made, protein can start being produced.

Question 17

Primary RNA transcript vs. mature RNA

Answer 17

Primary - sometimes will have a cap sometimes not, sometimes has introns
mature - fully processed, has a cap and poly A tail, only has exons left

Question 18

What do eukaryotic RNA polymerases require?

Answer 18

Transcription factors to help position them at promoter (similar to sigma factor)