ACTA2

For the EU Copyright Directive, see Directive on Copyright in the Digital Single Market.

ACTA2 (actin alpha 2) is an actin protein with several aliases including alpha-actin, alpha-actin-2, aortic smooth muscle or alpha smooth muscle actin (α-SMA, SMactin, alpha-SM-actin, ASMA). Actins are a family of globular multi-functional proteins that form microfilaments. ACTA2 is one of 6 different actin isoforms and is involved in the contractile apparatus of smooth muscle. ACTA2 (as with all the actins) is extremely highly conserved and found in nearly all mammals.

ACTA2
Identifiers
Aliases	ACTA2, AAT6, ACTSA, MYMY5, actin, alpha 2, smooth muscle, aorta, actin alpha 2, smooth muscle
External IDs	OMIM: 102620; MGI: 87909; HomoloGene: 133938; GeneCards: ACTA2; OMA:ACTA2 - orthologs
Gene location (Human) Chr. Chromosome 10 (human)[1] Band 10q23.31 Start 88,935,074 bp[1] End 88,991,339 bp[1]
Gene location (Mouse) Chr. Chromosome 19 (mouse)[2] Band 19|19 C1 Start 34,218,490 bp[2] End 34,232,990 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in saphenous vein tail of epididymis right coronary artery popliteal artery tibial arteries urethra ascending aorta seminal vesicula body of uterus Descending thoracic aorta Top expressed in ascending aorta tunica media of zone of aorta aortic valve iris umbilical cord cervix calvaria migratory enteric neural crest cell internal carotid artery seminal vesicula More reference expression data BioGPS More reference expression data
Gene ontology Molecular function ATP binding nucleotide binding protein kinase binding Cellular component cytosol cytoplasm actin cytoskeleton smooth muscle contractile fiber cell body lamellipodium filopodium cytoskeleton extracellular exosome extracellular space protein-containing complex Biological process muscle contraction regulation of blood pressure vascular associated smooth muscle contraction mesenchyme migration positive regulation of gene expression glomerular mesangial cell development response to virus positive regulation of transcription, DNA-templated Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 59 11475 Ensembl ENSG00000107796 ENSMUSG00000035783 UniProt P62736 P62737 RefSeq (mRNA) NM_001141945 NM_001613 NM_001320855 NM_007392 RefSeq (protein) NP_001135417 NP_001307784 NP_001604 NP_031418 Location (UCSC) Chr 10: 88.94 – 88.99 Mb Chr 19: 34.22 – 34.23 Mb PubMed search [3] [4]
Wikidata
View/Edit Human View/Edit Mouse

In humans, ACTA2 is encoded by the ACTA2 gene located on 10q22-q24.^[5][6] Mutations in this gene cause a variety of vascular diseases, such as thoracic aortic disease, coronary artery disease, stroke, Moyamoya disease, and multisystemic smooth muscle dysfunction syndrome.^[5]

ACTA2 (commonly referred to as alpha-smooth muscle actin or α-SMA) is often used as a marker of myofibroblast formation.^[7] Studies have shown that ACTA2 is associated with TGF-β pathway that enhances contractile properties of hepatic stellate cells leading to liver fibrosis and cirrhosis.^[8]