Autophagy-related protein 12 (ATG12)

Autophagy-related protein 12 (ATG12) is a ubiquitin-like protein that serves as a fundamental component of the autophagic machinery, specifically in the formation and expansion of the autophagosome. It undergoes a covalent conjugation to ATG5, a process mediated by the E1-like enzyme ATG7 and the E2-like enzyme ATG10, to form the ATG12-ATG5 conjugate. This conjugate then non-covalently associates with ATG16L1 to form an E3-like ligase complex that is essential for the lipidation of LC3 (ATG8), a critical step for autophagosome membrane elongation and closure. Beyond its role in autophagy, ATG12 acts as a pro-apoptotic factor by interacting with and neutralizing anti-apoptotic proteins such as Mcl-1 and Bcl-2, thereby linking the autophagy and apoptosis pathways. In clinical settings, ATG12 is implicated in various diseases; for example, its upregulation is a known driver of resistance to HER2-targeted therapies in breast cancer, while its dysregulation is associated with neurodegenerative conditions like Parkinson's and Alzheimer's diseases. Therapeutic strategies targeting ATG12 are currently in the experimental stage, focusing on small-molecule inhibitors that disrupt its protein-protein interactions, such as the ATG12-ATG3 interface, to inhibit autophagy in "autophagy-addicted" cancers or to modulate inflammatory responses.

Other names

APG12APG12LFAP12HAPG12Autophagy-related 12

Inhibition of the ATG12-ATG3 protein-protein interaction or disruption of the ATG12-ATG5-ATG16L1 complex to block autophagosome formation and LC3 lipidation.