Homework SourseWhich of the following are examples of posttranslational gen
Which of the following are examples of post-translational gene regulation? Select all the correct answers.
| Activation of a protein under specific cellular conditions (for example stress) |
| Phosphorylation of a protein |
| A protein that targets a specific mRNA for degradation |
| Alternative splicing |
| Addition of ubiquitin to a protein targeting it for degradation |
Solution
a). Activation of a protein under specific cellular conditions (for example stress)
b). Phosphorylation of a protein
e). Addition of ubiquitin to a protein targeting it for degradation
Protein degradation is a part of protein regulation. Some of the proteins are degraded by the lysosomes. However, some of the proteins are also degraded outside the lysosomes by processes that require energy in the form of ATP.
During this process, the proteins to be degraded are tagged by the “ubiquitin” molecules, which are polypeptides of 76 amino acids length. These ubiquitin molecules bind to “lysine” of the target protein. Proteins tagged by the ubiquitin are then degraded by proteasomes.
Activation of inactive proteins only under specific cellular conditions (for example by phosphorylation), or inactivation of proteins either by phosphorylation or dephosphorylation are the two other mechanisms of post transcriptional gene regulation
