post-translational modifications Flashcards
1
Q
list three ways a protein could be modified post-translationally (there are 9)
A
- methylation
- ubiquidation
- phosphorylation
- acetylation
- SUMOylation
- lipidation
- hydroxylation
- glycosylation
- disulfide bond
2
Q
list 2 reasons why glycosylation could be important for a protein’s function
A
- carbohydrates are hydrophilic so they change the polarity and solubility
- serve as markers for protein to get to its cellular destination
- structural complexity forms a code
- facilitate cell-cell interactions
3
Q
what is one reason why lipidation could be important for a protein’s function?
A
- allows proteins to anchor in the membrane
- involved in cellular signal transduction
- helps in protein-protein interaction
4
Q
what is the most common function of ubiquidation?
A
- labeling proteins for proteasomal degradation
5
Q
what is a signal sequence?
A
- direct proteins to their cellular destination
6
Q
what is an example of a type of signal sequence that would not be cleaved?
A
Nuclear localization sequences (NLS) are not cleaved
7
Q
preprotein
A
- protein precursor that contains a signal peptide sequence that is cleaved