DCAF12 (DDB1 and CUL4 associated factor 12) functions as a substrate-recognition component of the CUL4-RING E3 ubiquitin ligase complex, recognizing C-terminal degrons in target proteins to direct their ubiquitination 1. The protein specifically recognizes diglutamate (Glu-Glu) motifs at the C-terminus of substrates like MAGEA3, MAGEA6, and CCT5, as well as alternative glutamate-leucine (Glu-Leu) degrons in proteins such as MOV10 12. DCAF12-mediated ubiquitination of MAGEA proteins is required for starvation-induced autophagy, while MOV10 regulation occurs during spermatogenesis and T cell activation 23. Beyond degradative functions, DCAF12 catalyzes non-degradative ubiquitination of TRiC/CCT chaperonin subunits, enhancing their folding capacity for cytoskeletal and oncogenic proteins 4. In cancer contexts, DCAF12 overexpression drives metastasis through YAP/STAT3/mTOR pathway activation and correlates with poor survival 4. Conversely, DCAF12 acts as an endogenous IAP antagonist, promoting apoptosis by blocking XIAP-caspase interactions and suppressing NF-κB signaling 5. At the neuromuscular junction, DCAF12 promotes neurotransmitter release and homeostatic plasticity 6. Clinically, DCAF12 expression is significantly reduced in myasthenia gravis patients and may serve as a diagnostic biomarker 7.