Ubiquitin-activating enzymes (E1)

Ubiquitin-activating enzymes, known as E1 enzymes, play a crucial role in a process called ubiquitination, which tags proteins for degradation or alteration in function. Think of E1 enzymes as "activators" that prepare a small protein called ubiquitin. They attach ubiquitin to themselves and then to other proteins that need to be marked for recycling or destruction. This process helps maintain cellular health by removing damaged or unneeded proteins, regulating various cellular functions, and influencing a wide range of biological processes, including immune response and cell cycle regulation.