UBE2QL1 is a ubiquitin-conjugating enzyme (E2 ligase) that catalyzes protein ubiquitination through its active-site cysteine residue 1. The protein functions in multiple cellular contexts: it interacts with the F-box protein FBXW7 to facilitate degradation of oncogenic substrates including CCNE1 and mTOR 1, and coordinates lysophagy—the selective autophagic clearance of damaged lysosomes 2. Upon lysosomal membrane permeabilization, UBE2QL1 translocates to damaged lysosomes where it promotes ubiquitination of lysosomal proteins, recruits the autophagy receptor p62 and the AAA-ATPase VCP/p97, and facilitates LC3B-mediated autophagosome formation 2. UBE2QL1 is essential for lysosomal homeostasis; its depletion increases basal lysosomal damage and impairs TFEB activation 2. Recent evidence indicates UBE2QL1 also participates in linear ubiquitination at damaged lysosomes to activate NF-κB signaling and promote cell survival 3. Clinically, UBE2QL1 acts as a renal tumor suppressor: it is disrupted by constitutional translocation in familial renal cell carcinoma and downregulated in 78.6% of sporadic cases through deletions and promoter hypermethylation 1. Its reexpression suppresses anchorage-independent growth in RCC cell lines 1. UBE2QL1 hypermethylation also associates with poor prognosis in clear cell RCC and hepatocellular carcinoma, suggesting broader cancer relevance 45.