Ubiquitination

Ubiquitination is a post-translational modification process where ubiquitin, a small protein, is attached to a target protein, marking it for degradation by the proteasome.

E3 is an enzyme that facilitates the transfer of ubiquitin from E2 (ubiquitin-conjugating enzyme) to the target protein, ensuring specificity in the ubiquitination process.

The degron tag is a specific sequence on a target protein that signals for its degradation; it is recognized by E3 during the ubiquitination process.

A mutation in E3 can disrupt its ability to bind to the target protein or E2, leading to failure in ubiquitination and subsequent degradation of the target protein.

A mutation in a lysine residue on ubiquitin can prevent the formation of polyubiquitin chains, affecting the degradation of target proteins.

E2 is a ubiquitin-conjugating enzyme that carries ubiquitin and transfers it to the target protein, playing a crucial role in the ubiquitination cascade.

Polyubiquitination is the process where multiple ubiquitin molecules are attached to a target protein, often signaling it for degradation by the proteasome.

A mutation in the active site of E2 can hinder its ability to transfer ubiquitin to the target protein, resulting in failure of ubiquitination.

Ubiquitin is a small protein that tags other proteins for degradation, regulates various cellular processes, and maintains protein homeostasis.

The proteasome is a large protein complex that degrades ubiquitinated proteins, recycling amino acids and maintaining cellular protein levels.