The mammalian homolog of the Drosophila protein Maelstrom is expressed in the male germline and localizes to the sex body in spermatocytes and the chromatoid body in round spermatids. Similar to its expression in Drosophila, Maelstrom is a component of nuages, a germ-cell specific organelle and is thought to be essential for spermatogenesis and transposon repression during meiosis. In humans, Maelstrom has been found to be expressed only in the testis and in various cancer cell lines. Treatment of these cell lines with the demethylating agent 5'-Aza-2-Deoxycytidine significantly upregulated Maelstrom levels, indicating that its expression is regulated by DNA methylation.Synonyms: Protein maelstrom homolog