Card Set Information
Cellular Molecular Biology
From gene to Protein
another word for mRNA
hnRNA; heteronuclear RNA
The job of U1 snRNP is?
forms bade-pairs with 5' splice juntion and BBP (branch-point binding protein)and U2AF recognizes the branch-point site.
How is the branch point site recognized?
U2AF (U2 auxillary factor) recognizes the branch point
What is a "spliceosome"?
formed snRNP complex, utilizes 'A' at the branch site to cut the hnRNA molecule at the 5' splice site
A ____ forms when an snRNP complex utilizes the branch site to ready the intron for splicing.
a loop called a lariat
What happens to the excised Intron lariat after it has been spliced out?
intron RNA will be degraded in the nucleus; snRNPs will be recycled
RNA polymerase __ transcribes RNA in the ___ to ___ direction.
II; 5' to 3' direction
____ ____ is a sequence of DNA that transcribes
In eukaryotes, transcriptional unit inludes _ gene(s). In prokaryotes, a transcriptional unit includes _ gene(s).
1 gene for eukaryotes; series of neighbouring genes for prokaryotes (think Lac operon)
RNA polymerase can ____ the DNA helix at the active site.
unwind the DNA to expose the template
the ___ ___ signals the initiation phase for transcription on RNA.
sigma factor; binds to RNA polymerase to create a haloenzyme.
what sequence signals termination in transcription?
ter sequences coded in the DNA cause RNA to form a loop; destablizes RNAs hold on DNA
the ____ has affinity for RNA
2 important characterisitcs of ter sequences?
1) sequences of DNA that codes for self-complimentary region; forms a loop in RNA to slow polymerase
2) series of U-nucleotides in RNA make dissosiation easier
TATAA box is located at the ___ region of the ____
RNA polymerase always moves in the ___ to ___ direction and synthesizes RNA in the ____ to ____ direction.
3' to 5'; 5' to 3'
Eukaryotic transcription involves __ RNA polymerases
3 RNA polymerases, RNA polymerase I,II, and III
RNA polymerase I is composed of 3 subunits. Name them
5.8s, 19s, and 28s . Codes for rRNA genes
RNA polymerase II codes for? In eukaryotes.
all-protein coding genes, snoRNA, miRNA, siRNA, and most snRNA
RNA polymerase III codes for? (eukaryotes)
tRNA, 5s rRNA genes, some sRNA genes and genes for other small RNAs
True/false: Mitochondrial RNA polymerase & chloroplast RNA polymerase are both similar to bacterial RNA polymerase
True/false: Not all RNA polymerases are composed of subunits.
False. All RNA polymerases are composed of subunits.
3 groups of transcription factors required in transcription of eukaryotic genes?
TFI, TFII, and TFIII