ACTR2

Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeletal proteins, including the alpha and beta spectrins and dystrophins. Alpha actinin is an actin-binding protein with multiple roles in different cell types. In nonmuscle cells, the cytoskeletal isoform is found along microfilament bundles and adherens-type junctions, where it is involved in binding actin to the membrane. In contrast, skeletal, cardiac, and smooth muscle isoforms are localized to the Z-disc and analogous dense bodies, where they help anchor the myofibrillar actin filaments. This gene encodes a muscle-specific, alpha actinin isoform that is expressed in both skeletal and cardiac muscles. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2013]

Full Name

Actinin Alpha 2

Function

ATP-binding component of the Arp2/3 complex, a multiprotein complex that mediates actin polymerization upon stimulation by nucleation-promoting factor (NPF). The Arp2/3 complex mediates the formation of branched actin networks in the cytoplasm, providing the force for cell motility. Seems to contact the pointed end of the daughter actin filament. In podocytes, required for the formation of lamellipodia downstream of AVIL and PLCE1 regulation. In addition to its role in the cytoplasmic cytoskeleton, the Arp2/3 complex also promotes actin polymerization in the nucleus, thereby regulating gene transcription and repair of damaged DNA. The Arp2/3 complex promotes homologous recombination (HR) repair in response to DNA damage by promoting nuclear actin polymerization, leading to drive motility of double-strand breaks (DSBs).

Biological Process

Arp2/3 complex-mediated actin nucleation
Associative learning
Asymmetric cell division
Cellular response to interferon-gamma
Cellular response to trichostatin A
Cilium assembly
Cytosolic transport
Ephrin receptor signaling pathway
Establishment or maintenance of cell polarity
Fc-gamma receptor signaling pathway involved in phagocytosis
Meiotic chromosome movement towards spindle pole
Meiotic cytokinesis
Membrane organization
Neutrophil degranulation
Positive regulation of dendritic spine morphogenesis
Positive regulation of double-strand break repair via homologous recombination
Positive regulation of lamellipodium assembly
Positive regulation of transcription by RNA polymerase II
Response to ethanol
Response to immobilization stress
Spindle localization

Cellular Location

Nucleus; Cytoskeleton; Cell projection