Anti-skr-1 antibodies enable researchers to detect and measure the skr-1 antigen in biological samples. This target is a reported synonym of the ACVR1 gene, which encodes activin A receptor type 1. The human version of skr-1 has a canonical amino acid length of 509 residues and a protein mass of 57.2 kilodaltons. It is reported to be localized in the membrane of cells and notably expressed in many tissues, such as the smooth muscle and thyroid gland. skr-1 is a member of the TKL Ser/Thr protein kinase protein family.