Transcription 1 Flashcards
(20 cards)
What is transcription
Process where RNA is made using DNA as a template
What is required for RNA polymerization?
RNA Polymerase
What direction does RNA polymerase synthesize?
DOES NOT NEED A PRIMER,5’ - 3’, anti-parallel fashion, using phosphodiester bonds
What are the starting compounds that RNA polymerase utilizes?
ATP, GTP, CTP and UTP
What are the three types of RNA?
mRNA, tRNA and rRNA
What is mRNA?
Messenger RNA, carries message to be translated into protein
What is tRNA?
Transfer RNA, carries amino acids to ribosomes for incorporation into protein
What is rRNA?
Ribosomal RNA, the components of ribosomes
How many polypeptide subunits does E. Coli have?
Five
How many conserved sequences does E. Coli have?
Two - One at -10, relative to the transcription start site (TATAAT - Pribnow box), another at -35, relative to the transcription start site (TTGACA)
TATAAT is called the what?
Pribnow box
What makes a promoter more active at initiation transcription?
The more closely the sequence matches the consensus sequence of the -10 sequence
What is the Sigma Factor?
A protein that binds to other proteins in RNA polymerase and help polymerase to bind to the promoter
What happens with different Sigma Factors?
They can allow for the cell to turn on sets of genes with different sequences in the -10/-35 as needs arise
What is the strand being copied known as?
The template strand
How does the template strand run?
It will run 3’ - 5’ as it is complementary to the RNA being made.
What is the strand of DNA not being copied called?
IT is called the coding strand, since it has the same sequence as the RNA, but replaces U with T.
What controls transcription?
Promoters. The stronger RNA polymerase (prokaryotes) binds to the promoter, the more transcripts are made. The more transcripts, the promoter then is referred to as stronger.
What is the transcription bubble?
DNA polymerase situates between strands of DNA duplex and forms the bubble.
What does the bubble doe?
Moves down the DNA strand as the process of transcription occurs.
