Beta-actin

Beta-actin (human gene and protein symbol ACTB/ACTB) is one of six different is_associated_with::actin isoforms which have been identified in humans. This is one of the two nonmuscle is_associated_with::cytoskeletal actins. Actins are highly conserved proteins that are involved in cell motility, structure and integrity. Alpha actins are a major constituent of the contractile apparatus.

Interactions
Beta-actin has been shown to interact with is_associated_with::SPTBN2. In addition, is_associated_with::RNA-binding protein Sam68 was found to interact with the mRNA encoding β-actin, which regulates the synaptic formation of the dendritic spines with its cytoskeletal components.

Beta-actin has been shown to activate eNOS, thereby increasing NO production. An eight-amino acid residue (326-333) in actin has been shown to mediate the interaction between actin and eNOS

Clinical relevance
Recurrent mutations in this gene have been associated to cases of is_associated_with::diffuse large B-cell lymphoma.

Applications
Beta actin is usually used as a loading control, for among others, the integrity of cells, is_associated_with::protein degradation, in is_associated_with::PCR and is_associated_with::Western blotting. Its molecular weight is approximately 42 kDa.