Purified actin protein from rabbit skeletal muscle.

Actin Protein

Actin, like tubulin, is a superfamily of cytoskeletal proteins that provide shape and structure to the eukaryotic cell. G-actin (globular actin) is the monomeric subunit that polymerizes into linear microfilaments termed F-actin (filamentous actin). Actin is required for several essential eukaryotic processes including muscle contraction, cell motility, cell junctions, and cytokinesis. Multiple actin isoforms are differentially expressed in various tissues, including α-cardiac, α-skeletal, α-smooth muscle, γ-smooth muscle, and non-muscle β- and γ-actin. Prokaryotic actin homologs also exist. G-actin polymerizes into higher order actin filaments that, together with myosin motor proteins, form the contractile machinery of the cell. Two parallel F-actin strands create a double helix structure with a diameter of ~7 nm. Given the asymmetry of G-actin, actin filaments have inherent polarity with distinct “pointed” and “barbed” ends. Each actin monomer is bound to a molecule of adenosine triphosphate (ATP) and a Mg2+ cation. The ATPase activity of G-actin confers dynamic “treadmilling” capabilities to actin filaments that are critical for cell motility and muscle contraction, and genetic mutations in actin can cause a number of human pathologies including cardiomyopathies and deafness. Given its remarkable properties and relevance to human health and disease, actin has been the subject of intensive research across multiple disciplines for many decades.

We specialize in isolating and modifying native actin proteins for in vitro research use. Our stocked actin proteins are derived from rabbit skeletal muscle and lyophilized for long-term storage at ambient temperatures. We offer a range of purity levels as well as custom services including actin labeling or purification from diverse sources.