alpha-Smooth Muscle Actin: Proteins and Enzymes

Actin makes up the most abundant protein in many eukaryotic cell types. It polymerizes forming microfilaments that have an array of functions including regulating contractility, motility, cytokinesis, phagocytosis, adhesion, cell morphology, and providing structural support. At least six types of Actin, falling into three categories, exist in higher eukaryotes. The three types, separated based on isoelectric point, include a (alpha-Skeletal, alpha-Cardiac, alpha-Smooth Muscle), beta (beta-Non-muscle) and gamma (gamma-Smooth Muscle, gamma-non-muscle) isoforms.