The protein encoded by ACTA2 gene belongs to the actin family of proteins, which are highly conserved proteins that play a role in cell motility, structure and integrity. Alpha, beta and gamma actin isoforms have been identified, with alpha actins being a major constituent of the contractile apparatus, while beta and gamma actins are involved in the regulation of cell motility. This smooth muscle specific alpha actin (SMA) stains actin from smooth muscle cells, myoepithelial cells, and myofibroblasts without cross-reaction of skeletal muscle. SMA is used especially for detection of leiomyomatous and myofibroblastic tumours, GIST and mesenchymal tumors.
The protein encoded by ACTA2 gene belongs to the actin family of proteins, which are highly conserved proteins that play a role in cell motility, structure and integrity. Alpha, beta and gamma actin isoforms have been identified, with alpha actins being a major constituent of the contractile apparatus, while beta and gamma actins are involved in the regulation of cell motility. This smooth muscle specific alpha actin (SMA) stains actin from smooth muscle cells, myoepithelial cells, and myofibroblasts without cross-reaction of skeletal muscle. SMA is used especially for detection of leiomyomatous and myofibroblastic tumours, GIST and mesenchymal tumors.