This gene encodes the beta subunit of a highly conserved filamentous actin capping protein that binds the barbed end of filamentous actin to stabilize it and terminate elongation. Interaction of this protein with the barbed end of the actin filament occurs through binding of the amphipathic helix at the C-terminus to the hydrophobic cleft on the actin molecule. This gene is required for a variety of dynamic actin-mediated processes including organization of lamellipodia and filopodia, growth cone morphology and neurite outgrowth in hippocampal neurons, and asymmetric spindle migration and polar body extrusion during oocyte maturation. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2015]