Transmembrane protein 225 (TMEM225)

Transmembrane protein 225 (TMEM225) is a four-pass transmembrane protein expressed predominantly in the testis. It is evolutionarily conserved and found across species, including humans, rodents, and other mammals. TMEM225 localizes primarily to the nuclear envelope and cytoplasmic vesicles, with specific expression in spermatocyte and round spermatid stages. Functional studies in knockout mice indicate that TMEM225 is not required for spermatogenesis but is essential for the maturation of sperm within the epididymis, particularly affecting flagellar structure and mitochondrial function. Mutations or deletions in TMEM225 result in defective motility, abnormal sperm flagella, increased reactive oxygen species, and consequent male infertility of the asthenozoospermic type. TMEM225 likely functions in the regulation of protein phosphatase 1 activity during spermatid development, although the complete molecular mechanism remains to be clarified. No current drugs or therapeutic approaches target TMEM225; its main relevance is in male reproductive biology and potential as an infertility biomarker.

Other names

PMP22 claudin domain-containing proteinPMP22CDPPP1R154SPATA47protein phosphatase 1, regulatory subunit 154spermatogenesis associated 47

Not established for any drugs; suspected molecular function relates to inhibition or regulation of protein phosphatase 1 (PP1)