MOAP1 (modulator of apoptosis 1) is a multifunctional protein that serves as a critical regulator of apoptosis and cellular stress responses. The protein acts as an effector of BAX during apoptosis, associating with BAX upon apoptotic induction to facilitate mitochondrial outer membrane permeabilization and promote apoptotic cell death 1. MOAP1 is required for death receptor-dependent apoptosis and can be targeted by microRNAs such as miR-92a-3p and miR-25, which regulate its expression in cancer and vascular contexts 21. Beyond apoptosis, MOAP1 plays a distinct role in autophagy regulation by binding to LC3 proteins through its N-terminal LC3-interacting region (LIR) motif, promoting efficient phagophore closure during starvation-induced autophagy 3. Structurally, MOAP1 is a retrotransposon-derived protein with domains similar to retroviral Gag proteins, suggesting evolutionary origin from ancient viral integrations 4. The protein's stability is regulated by TRIM68 through K63-linked polyubiquitination, and MOAP1 expression is frequently downregulated in cancers, where its restoration can inhibit tumor proliferation and metastasis 5. Additionally, MOAP1 enhances antiviral immunity by promoting RIG-I signaling pathway activation against RNA viruses 6.