Eukaryotic Transcription

Question 1

What is monocistronic?

Answer 1

mRNA with a single cistron

Question 2

Are most eukaryotic genes monocistronic or polycistronic?

Answer 2

Monocistronic

Question 3

What does transcription from the eukaryotic genes produce?

Answer 3

Immature, pre-mRNA which gets post-transcriptionally processed to produce mature mRNA

Question 4

Where does mature mRNA gets translated?

Answer 4

In the cytoplasm

Question 5

What do eukaryotes have that makes them so complicated?

Answer 5

3 types of RNA (5 in plants), gazillions of more proteins in transcription initiation, exons and introns in their protein CDS, another gazillion of proteins for RNA processing, even their DNA is packaged in a more complex way

Question 6

What is the function of enhancer elements?

Answer 6

Controls transcription efficiency

Question 7

What is an exon?

Answer 7

Part of CDS which gets transcribed to RMA and encodes the protein

Question 8

What is an intron?

Answer 8

Part of CDS which gets transcribed but does not code for protein is found in between the exons of the CDS

Question 9

What are UTRs?

Answer 9

Regions of a gene that are transcribed, but not translated, are found 5’ and 3’ of the protein CDS

Question 10

What are the 2 parts of class II promoter?

Answer 10

• Core promoter: 6 elements
• upstream element

Question 11

What is the function of class II promoter?

Answer 11

Points RNA polymerase to the correct direction for transcription

Question 12

What does the general transcription factors (GTFs) do?

Answer 12

They help RNA polymerase II interact with the core promoter elements

Question 13

What are the 6 GTFs that are used to initiate transcription from the class II promoter?

Answer 13

GTFIIA - GTFIIH

Question 14

What is the function of activator proteins?

Answer 14

They further regulate eukaryotic transcription

Question 15

What is the function of the mediator protein?

Answer 15

It bridges the interaction between activator or enhancers and the proteins bound to the core promoter elements (RNA polymerases, GTFs, etc.)

Question 16

What is the benefit of having multiple activators or enhancers?

Answer 16

It allow cells to control transcription more precisely.

Question 17

What does the protein do to perform their function?

Answer 17

They interact with one another (protein-protein interaction) and with other parts of DNA (protein-DNA interaction)

Question 18

What are the two enzymatic activities of TFIIH?

Answer 18

helicase and kinase

Question 19

What is helicase activity?

Answer 19

TFIIH unwinds DNA using its XPB and XPD subunits

Question 20

What is kinase activity?

Answer 20

TFIIH phosphorylates the 5th Serine of the RNA polymerase II C-terminal domain repeat

Question 21

What is RNA polymerase II CTD?

Answer 21

A repeat of 7 amino acid sequence, YSPTSPS

Question 22

When does most of RNA processing happen?

Answer 22

During elongation

Question 23

What allows RNA polymerase II to enter the elongation phase?

Answer 23

Phosphorylation of RNA polymerase II

Question 24

What is phosphorylated in RNA polymerase II CTD?

Answer 24

5th Serine of every repeat

Question 25

What are the first two amino acids at the start of an intron?

Answer 25

GU

Question 26

What is the branching point?

Answer 26

Adenine

Question 27

What are the conserved nucleotides?

Answer 27

5’ GU and 3’ AG

Question 28

What are the last two amino acids of an intron?

Answer 28

AG

Question 29

What is the branch point sequence?

Answer 29

YNYURAY