Tropomyosin alpha-3 chain, also known as TPM3, is member of the tropomyosin family of actin-binding proteins involved in the contractile system of striated and smooth muscles and the cytoskeleton of non-muscle cells. Tropomyosins are dimers of coiled-coil proteins that polymerize end-to-end along the major groove in most actin filaments. They provide stability to the filaments and regulate access of other actin-binding proteins. Mutations in this gene result in autosomal dominant nemaline myopathy, and oncogenes formed by chromosomal translocations involving this locus are associated with cancer. Recombinant human TPM3 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.