Exam 1 part 3 Flashcards
1
Q
Central Dogma of Molecular Biology
A
DNA can replicate itself
DNA can be transcribed to (m)RNA
RNA can be translated to a polypeptide
2
Q
coding strand
A
where the gene is marked. Includes promoters, +1 site, terminator
3
Q
+1 site
A
where transcription begins
4
Q
promoter
A
site where sigma site attaches to place RNA polymerase
5
Q
Molecules involved in transcription
A
mRNA transcription factors template strand RNA polymerase NTPs
6
Q
Transcription overview
A
- DNA is locally denatured
- RNA polymerase assembles NTP complementary to the template strand
-reads the template 3’-5’
SYNTHESIZES 5’-3’
No primer needed
7
Q
Steps in transcription
A
- Initiation
- Elongation
- Termination
8
Q
Initiation in E coli
A
Sigma binds to 2 conensus sequences -10 box -35 box to orient the polymerase at +1 site 2. RNA polymerase can start synthesizing RNA -does not need a primer
9
Q
nascent
A
new
10
Q
Termination in E. coli
A
hairpin in RNA causes pol to stop transcribing
RNA-DNA duplex is dissociated by helicase p (Rho)
11
Q
Prok vs Euk transcription
A
Prok-1 RNA pol - no RNA processing -coupled transcription &translation polycistronic RNA Euk-2 RNA pol -introns removed -nuclear membrane prevents coupling -nuclear export -capping and polyadenylation monocystronic
