Question

Contrast eukaryotic transcription with prokaryotic transcription

a. Types of RNAP, subunits of RNAP

b. Regulation

c. Elements of preinitiation complex

d. Stages of transcription: initiation, elongation, termination

Answer 1

	Prokaryotic transcription	Eukaryotic transcription
Location	Cytoplasm	Cell's nucleus
RNA Polymerase sub units	5 subunits	10 - 17 subunits
RNA Polymerase	Holo enzyme recognises and directly binds to the promoter	Promoter recognition cannot be carried out by RNA polymerase alone
Regulation	Positive and negative control by regulatory proteins that act at sites close to the promoter	Positive and negative control by regulatory proteins that act at sites close to and far from the promoter
Elements of preinitiation complex	RNA polymerase along with the sigma factor interacts with promoter	Pre initiation complex includes RNA polymerase II and 6 transcription factors
Promoter Structure	-35 box and -10 box	More variable TATA box about -30 from the start point
Stages of transcription	General process and basic biochemistry is the same for both.	General process and basic biochemistry is the same for both. It is far more complicated than prokaryotes
mRNA	Polycistronic	Monocistronic
mRNA processing	mRNA is transcribed directly from template DNA molecule	Pre mRNA is formed first and then processed to yield a mature mRNA