Myosin-binding protein C, cardiac-type (MYBPC3) (MYBPC3)

Myosin-binding protein C, cardiac-type (MYBPC3) is a structural protein essential for the stability and regulatory function of the cardiac sarcomere [UniProt: Q14896]. It binds to both myosin and actin, acting as a molecular brake to regulate the kinetics of cross-bridge cycling and muscle contraction [PubMed: 28334592]. Loss-of-function mutations in the MYBPC3 gene, often leading to protein haploinsufficiency, are the most frequent genetic cause of hypertrophic cardiomyopathy (HCM) [PubMed: 31513740]. These mutations result in sarcomere disorganization, hypercontractility, and impaired relaxation, which can progress to heart failure or sudden cardiac death [NCBI Gene: 4607]. Therapeutic approaches include gene replacement therapies like TN-201, which aim to restore functional MYBPC3 levels, and small-molecule myosin inhibitors such as mavacamten that address the downstream hypercontractile phenotype [ClinicalTrials.gov: NCT05836259].

Other names

Cardiac MyBP-CC-protein, cardiac muscle typeMYBPC3

Gene replacement therapy to restore MYBPC3 protein levels; Myosin inhibition to reduce hypercontractility associated with MYBPC3 deficiency.