6.1 Transcriptional & Translational Control Flashcards
(RNA processing) what type of molecule is pre mRNA?
Precursor molecule
(RNA processing) what is added to pre mRNA before it can bind to a ribosome?
A cap and a tail
(RNA processing) what is a cap and where is it added?
Modified nucleotide
Added to the 5 prime end
(RNA processing) what is a tail and where is it added?
Long chain of Adenine nucleotides
Added at the 3 prime end
(RNA processing) what do the cap and tail do?
Help stabilise mRNA
Delay degradation in the cytoplasm
Cap aids binding of mRNA to ribosomes
(RNA editing) how can the nucleotide sequence of some mRNA molecules be changed?
Base addition, deletion or substitution
(RNA editing) what do changes to mRNA molecules result in?
Indifferent proteins with different functions
(RNA editing) changes to the mRNA nucleotide sequence can increase the range of what?
Proteins produced from a single mRNA molecule
(Translational control) how does slowing degradation of mRNA regulate protein synthesis?
More resistant a molecule the longer it lasts in the cytoplasm so more protein is synthesised
(Translational control) how do inhibitory proteins regulate protein synthesis?
Bind to mRNA preventing it from binding to ribosomes
(Translational control) how do activation of initiation factors regulate protein synthesis?
Aid the binding of mRNA to ribosomes
(Protein kinases) what are protein kinases?
Enzymes that catalase addition of phosphate groups to proteins
(Protein kinases) what do protein kinases change?
Tertiary structure of proteins and their function
(Protein kinases) what are many enzymes activated by?
Phosphorylation
(Post translational) involves modifications to what?
Proteins that have already been synthesised