Biochemistry - Transcription Flashcards
What are the two steps of protein synhesis?
Transcription
Trnaslation
RNA polymerase
This is the the primary gene expression enzyme transcribing DNA into RNA.
What does RNAP II do?
Primary eukaryotic polymerase for all protein-coding genes and non=protein RN like nuclear RNA.
What does RNAP III do?
Transcribes tRNA genes and the 5S component of rRNA.
What is gene regulation mediated by?
Promoters like enhancers and silencers.
Promoters
Regulatory regiosn where polymerases or TFs bind to initate gene transcription
What region do RNAP bind?
The TATA box of the promoter.
TATA box
This defines transcription direction and indicates the DNA strand to be read
How do enhancers and silencers work?
Bind the TATA box and regulate their activity.
What is required of the chromosome for transcription?
Chromatin remodelling complex opening of nucleosomes.
What are the five TF mediating RNAPII function?
TFFIIB, E, D, F and H
Why does so much cell variety exist in organisms?
Due to the variability by gene regulatory networks like enhancers and silencers.
Gene Regulatory Networks
Molecular regulators interacting with TFs and genes to regulate mRNA expression
Enhancers
Amplify gene expression, can be up to 1 million base pairs away, but on average 100-1000 bp.
Intergenic
In between active genes