This gene 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. [provided by RefSeq, May 2010],