Actin Related Protein T1 (ACTRT1)

ACTRT1 encodes a protein related to the cytoskeletal protein beta-actin. This protein is a major component of the calyx in the perinuclear theca of mammalian sperm heads, and it therefore likely functions in spermatid formation. This gene is intronless and is similar to a related gene located on chromosome 1. A related pseudogene has also been identified approximately 75 kb downstream of this gene on chromosome X.

The deduced 376-amino acid protein shares 49.3% amino acid identity with beta-actin (ACTB) and 75.5% identity with ARPT2. Both ARPT1 and ARPT2 contain several cysteine residues not found in beta-actin or other ARPs. Bovine Arpt1 showed an apparent molecular mass of about 40 kD.