Capping Protein Muscle Z Line Alpha 1 (CAPZa1)

CAPZA1 is a member of the F-actin capping protein alpha subunit family. This gene encodes the alpha subunit of the barbed-end actin binding protein. The protein regulates growth of the actin filament by capping the barbed end of growing actin filaments.

CapZ was identified in chicken as a nonsevering, barbed-end actin-binding protein composed of alpha and beta subunits. In the chicken, 2 cDNAs were isolated for the alpha subunit. The alpha-1 and alpha-2 (CAPZA2) isoforms, which share 85% identity, are the products of 2 separate genes; 1 gene appears to be responsible for beta-subunit expression. By capping the barbed end of actin filaments, CapZ regulates the growth of the actin filament at the barbed end.