TRIM63 (also known as MuRF1) is an E3 ubiquitin ligase that plays a critical role in skeletal and cardiac muscle protein degradation and atrophy 1. The protein functions as a muscle-specific ubiquitin ligase that is transcriptionally upregulated under atrophy-inducing conditions, making it an excellent marker of muscle atrophy 1. TRIM63 mediates proteasomal degradation of muscle proteins during catabolic states, with its mRNA expression dramatically increased during conditions such as mechanical ventilation-induced diaphragm atrophy (590% higher ratio) 2 and sepsis-induced muscle wasting 3. The gene is regulated by multiple signaling pathways, including the IL-6/gp130/JAK2/STAT3 pathway during sepsis, where JAK2 inhibition significantly reduces TRIM63 expression and attenuates muscle atrophy 3. Additionally, TRIM63 expression is modulated by CARM1, which governs autophagic and atrophic processes fundamental to muscle mass maintenance 4. In cardiac muscle, TRIM63 has clinical significance as variants cause familial hypertrophic cardiomyopathy, with recent evidence supporting moderate validity for autosomal recessive inheritance patterns 5. The gene represents a key therapeutic target for preventing muscle wasting in various pathological conditions including cancer cachexia and intensive care unit-acquired weakness.