ACTC1

ACTC1 Full Name

actin, alpha, cardiac muscle 1

ACTC1 Introduction

ACTC1, or actin alpha cardiac muscle 1, encodes the cardiac-specific α-actin isoform that is a fundamental component of the contractile apparatus in cardiomyocytes. This highly conserved protein polymerizes into thin filaments within the sarcomere, where it interacts with myosin, tropomyosin, and the troponin complex to enable force generation and coordinated heart contraction. ACTC1 is predominantly expressed in cardiac muscle and, to a lesser extent, in fetal skeletal muscle, reflecting its essential role in heart development and lifelong cardiac function. Its precise spatial organization and regulated expression are critical for maintaining normal myocardial structure and performance.

Figure 1. Cellular locations and functions of proteins, encoded by sarcomeric and minor HCM-associated genes.(Sources: Chumakova OS, et al.; 2023)

Functionally, ACTC1 provides the structural scaffold necessary for sarcomere assembly and efficient excitation–contraction coupling. By binding to regulatory proteins, α-cardiac actin translates calcium-dependent signaling into mechanical contraction, allowing the heart to respond dynamically to physiological demands. ACTC1 also contributes to mechanotransduction, helping cardiomyocytes sense and adapt to changes in mechanical load. Experimental studies show that even subtle alterations in ACTC1 structure or expression can disrupt filament stability, impair force transmission, and alter contractile kinetics, underscoring its central role in maintaining cardiac contractility and cellular integrity.

Clinically, mutations in ACTC1 are linked to a spectrum of inherited cardiomyopathies and congenital heart diseases. Pathogenic variants have been identified in hypertrophic cardiomyopathy, dilated cardiomyopathy, and restrictive cardiomyopathy, where they impair sarcomeric function and lead to progressive heart failure or arrhythmias. ACTC1 mutations are also associated with atrial septal defects and other developmental cardiac abnormalities, highlighting its importance in early heart morphogenesis. Because of its disease associations and tissue specificity, ACTC1 serves as a valuable molecular marker in cardiovascular genetics and translational research, with ongoing interest in its potential role in precision diagnostics and targeted therapies for cardiac disorders.

Alternate Names for ACTC1

ACTC1; actin, alpha, cardiac muscle 1; actin, alpha cardiac muscle 1; alphac-actin; actin alpha cardiac; alpha-cardiac actin; Actc-1;

• 1. Chumakova OS, Baulina NM. Advanced searching for hypertrophic cardiomyopathy heritability in real practice tomorrow. Front Cardiovasc Med. 2023, 10:1236539.