TIMM23 (translocase of inner mitochondrial membrane 23) is an essential component of the TIM23 complex, which mediates translocation of transit peptide-containing proteins across the mitochondrial inner membrane 1. Beyond protein import, TIMM23 plays a critical role in mitochondrial quality control through mitophagy regulation. TIMM23 protects PINK1 from OMA1-mediated degradation and facilitates its accumulation at the outer mitochondrial membrane in response to mitochondrial depolarization, thereby activating stress-induced mitophagy 2. This function is particularly relevant in neurodegenerative diseases; impaired mitophagy due to defective PINK1-PRKN signaling is implicated in Parkinson disease pathogenesis and Alzheimer disease 2. TIMM23 also functions within the broader mitochondrial quality control network, responding to import defects through protease-mediated regulation 3. When mitochondrial import is blocked, YME1L1 selectively degrades TIMM23 components, preventing accumulation of stalled precursors and protecting cellular viability. Dysfunction of TIMM23-dependent processes contributes to mitochondrial homeostasis failure in various pathological contexts, including drug-induced liver injury and intervertebral disc degeneration 45. Thus, TIMM23 integrates protein translocation and mitophagy functions essential for organellar quality control and disease prevention.