Actin, alpha skeletal muscle is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
that in humans is encoded by the ''ACTA1''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
.
Actin alpha 1 which is expressed in skeletal muscle is one of six different actin isoforms which have been identified. Actins are highly conserved proteins that are involved in cell motility, structure and integrity. Alpha actins are a major constituent of the contractile apparatus.
Skeletal actin gene expression
Skeletal alpha actin expression is induced by stimuli and conditions known to cause muscle formation. Such conditions result in fusion of committed cells (satellite cells) into myotubes, to form muscle fibers. Skeletal actin itself, when expressed, causes expression of several other "myogenic genes", which are essential to muscle formation. One key transcription factor that activates skeletal actin gene expression is Serum Response Factor ("SRF"), a protein that binds to specific sites on the promoter DNA of the actin gene. SRF may bring a number of other proteins to the promoter of skeletal actin, such as androgen receptor, and thereby contribute to induction of skeletal actin gene expression by androgenic (often termed "anabolic") steroids.
Interactions
Actin, alpha 1 has been shown to
interact with
TMSB4X,
and
PRKCE.
Clinical significance
Mutations in the ACTA1 gene are known to cause the following conditions:
* Nemaline myopathy 3 (NEM3);
* Myopathy, actin, congenital, with excess of thin myofilaments (MPCETM);
* Myopathy, congenital, with fiber-type disproportion (CFTD);
* Myopathy, scapulohumeroperoneal (SHPM).
See also
*
Actin
Actin is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells, where it may be present at a concentration of ...
*
ACTB
Actin beta (HUGO Gene Nomenclature Committee abbreviation ''ACTB''/ACTB) is one of six different actin isoforms which have been identified in humans. This is one of the two nonmuscle cytoskeletal actins. Actins are highly conserved proteins that ...
References
Further reading
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External links
GeneReviews/NCBI/NIH/UW entry on Nemaline Myopathy*
{{Cytoskeletal Proteins