A heterodimeric microfilament capping protein (capping protein, cap32/34, α, 286 aa; β, 277 aa) that binds to the barbed (assembly) end, blocking further G-actin addition. It is calcium-insensitive and does not sever filaments. There are multiple isoforms, some tissue-specific, and in muscle it is found in the Z-disc (sometimes called β-actinin). CapZ-interacting protein (protein kinase substrate CapZIP, 416 aa) is phosphorylated in stress conditions and then binds to, and inhibits, capZ.
Subjects: Medicine and Health.