Lecture 3 and 4 - RNAP and mechanisms of initiation and elongation

Question 1

Explain the initiation recruitment cascade.

Answer 1

TBP binds to TATA box of promoter
TFB binds to TBP-TATA complex, and recruits RNAP to form PIC

TFE then binds to facilitate strand separation

Question 2

What TFE binding sites were discovered by NPS?

Answer 2

TFE WH domain on the clamp coil
TFE-ZR domain on the clamp base

Question 3

What clamp prevents RNA escape?

Answer 3

Elf1-Spt5NGM-Spt4 clamp prevents RNA escape

Question 4

What factor reduces transcription elongation?

Answer 4

Elf1

Question 5

What is the RNA escape cascade?

Answer 5

RNAP–> Spt4/5 –> Elf1

Question 6

Describe transcription arrest and reinitiation

Answer 6

TFS1-ZRn is a jaw like anchor
TFS1-ZRc is inserted into the active site
RNA cleavage takes place and reactivation of transcription ensues

Question 7

What factor is responsible for transcription termination?

Answer 7

Spt5KOW