CAPZB
Description
The CAPZB (capping actin protein of muscle Z-line subunit beta) is a protein-coding gene located on chromosome 1.
CAPZB, also known as CapZβ, is a protein encoded by the CAPZB gene in humans. It functions to cap actin filaments at their barbed ends, preventing further elongation or shortening. CAPZB can exist in three forms due to alternative splicing: CapZβ1, CapZβ2, and CapZβ3. It forms a heterodimer with an alpha subunit (CAPZA1) to create the complete capping protein complex. In muscle cells, the CAPZB complex is found at the Z-disc, interacting with other proteins like α-actinin, nebulette, nebulin, and HSC70. CAPZB is crucial for maintaining the structure and function of the cytoskeleton.
CAPZB, also known as CapZβ, binds to the fast-growing ends of actin filaments (barbed end) in a calcium-independent manner. This prevents the addition or removal of actin subunits at these ends, effectively stabilizing the filament. Unlike other capping proteins, CAPZB does not break down actin filaments. This protein plays a crucial role in regulating cell shape and organization of the cytoskeleton. CAPZB forms a complex with CAPZA1 to create the barbed end of actin filaments in the dynactin complex, which helps to stabilize the dynactin structure. Dynactin, in turn, activates the dynein motor protein for long-distance movement along microtubules.
CAPZB is also known as CAPB, CAPPB, CAPZ.
