Lecture 12 Flashcards
Unidirectional
Information can only go in one direction
Gene
A region of DNA that is transcribed and has a function in the cell
Promoter
Site of RNA polymerase assembly, DNA sequence that determines start of gene, no promoter means no gene
TATA Box
AT rich sequence found 10 base pairs before transcription start
Transcription Factors
Proteins that recognize and bind the TATA box, can read DNA, recruits RNA polymerase because RNA pol can’t identify promoter on its own
Transcription
DNA to mRNA
Template Strand
Used in transcription, runs 3’ to 5’ away from promoter
Coding Strand
Complementary and antiparallel to template, runs 5’ to 3’ away from promoter, not used in transcription
Transcript
mRNA product
RNA Polymerase
Enzyme of transcription, part of a transcription initiation complex that assembles at the promoter, can open DNA into a transcription bubble
UTR
Untranslated region, space on RNA either before translation start or after translation stop
Elongation
Occurs where RNA polymerase add nucleotides 5’ to 3’ and transcript is released out of complex
Post-transcriptional Processing
Eukaryotes only, occurs in nucleus, increase stability of transcript
meG Cap
Methylguanosine cap, modified base, forms a 5’ to 5’ linkage with eukaryotic mRNA to hide 5’ end from exonuclease digestion
PolyA Tail
Added to 3’ end of eukaryotic mRNA, delays exonuclease digestion and aids in translation initiation.
RNA Splicing
Removal of intervening sequences from coding region (introns)
Introns
Non-amino acid coding regions which contain intervening sequences found in a eukaryotes gene’s DNA but not in the mature mRNA