BNIP3L (BCL2 interacting protein 3 like) is a mitochondrial outer membrane protein that serves as a critical regulator of mitochondrial homeostasis through multiple cellular pathways. Primary Function: BNIP3L functions as a mitochondrial cargo receptor that mediates mitophagy—the selective autophagic removal of dysfunctional or excess mitochondria 1. It recognizes autophagosomes and facilitates mitochondrial elimination, a process initially characterized during reticulocyte development 1. Additionally, BNIP3L participates in mitochondrial quality control through interaction with SPATA18/MIEAP, mediating mitochondrial-associated degradation of damaged proteins (MALM) 2. Mechanism: BNIP3L induces apoptosis and can overcome anti-apoptotic suppressors BCL-2 and BCL-XL, although high BCL-XL expression inhibits this function [UniProt]. It functions alongside BNIP3 and other mitochondrial cargo receptors in stress-responsive mitophagy, regulated by signaling pathways including AMPK, ATF4, FoxOs, and sirtuins 2. Disease Relevance: BNIP3L-mediated mitophagy is implicated in cancer progression, neurological disorders 1, autoimmune diseases including inflammatory bowel disease and systemic lupus erythematosus 3, age-related macular degeneration 4, and intervertebral disc degeneration 5. Clinical Significance: BNIP3L represents a potential therapeutic target for modulating disease pathways involving mitochondrial dysfunction, particularly in cancer treatment optimization and neurodegenerative disease management.