Protein Degradation

Question 1

E1

Answer 1

ubiquitin-activating enzyme; ATP - dependent enzyme, activates ubiquitin,

Question 2

E2

Answer 2

ubiquitin-carrier protein - brings ubiquitin to E3

Question 3

E3

Answer 3

ligase - adds ubiquitin to protein desired for degradation.

Question 4

Process of ubiquination

Answer 4

1) E1 activating enzyme; forms thioester bond with C-terminal of gly of ubiquitin 2) Ubiquiting is transferred to a cys-thiol of E2, the ubiquitin carrier protein 3) E3 ligase selects proteins for degradation. the E2-S-ubiquitin complex transfers ubiquitin to lys of selected proteins.