SRFBP1 (serum response factor binding protein 1) is a multifunctional RNA-binding protein with roles in transcriptional regulation, viral entry, and metabolic processes. As a serum response factor (SRF) cofactor, SRFBP1 regulates transcriptional activation of cardiac genes during aging 1, modulating histone acetylation and suppressing expression of mitochondrial biogenesis factors like PGC-1α and mitofusin proteins 1. SRFBP1 overexpression reduces mitochondrial function and oxygen consumption, suggesting involvement in age-related cardiac decline 1. The protein interacts with NADH dehydrogenase subunit NDUFAB1, altering the NAD/NADH ratio and affecting cellular metabolism 2. Beyond cardiac function, SRFBP1 serves as an HCV-specific, pan-genotypic host entry factor, facilitating hepatitis C virus entry through CD81-mediated interactions 3. Functionally, SRFBP1 regulates ribosomal RNA synthesis 4 and is implicated in adipose tissue metabolism, with genetic variants associated with visceral adiposity in males 5. Disease relevance includes glaucoma susceptibility, with rare deleterious mutations identified in primary open-angle glaucoma families 6, and potential involvement in bronchopulmonary dysplasia as an inflammation-related gene 7.