title: Expression of Atp8b3 in murine testis and its characterization as a testis specific P-type ATPase.
abstract: Spermatogenesis is a complex process that produces haploid motile sperms from diploid spermatogonia through dramatic morphological and biochemical changes. P-type ATPases, which support a variety of cellular processes, have been shown to play a role in the functioning of sperm. In this study, we isolated one putative androgen-regulated gene, which is the previously reported sperm-specific aminophospholipid transporter (Atp8b3, previously known as Saplt), and explored its expression pattern in murine testis and its biochemical characteristics as a P-type ATPase. Atp8b3 is exclusively expressed in the testis and its expression is developmentally regulated during testicular development. Immunohistochemistry of the testis reveals that Atp8b3 is expressed only in germ cells, especially haploid spermatids, and the protein is localized in developing acrosomes. As expected, from its primary amino acid sequence, ATP8B3 has an ATPase activity and is phosphorylated by an ATP-producing acylphosphate intermediate, which is a signature property of the P-Type ATPases. Together, ATP8B3 may play a role in acrosome development and/or in sperm function during fertilization.
authors.affiliation: School of Biological Sciences and Technology, Hormone Research Center, Chonnam National University, Gwangju, Republic of Korea.
authors.forename: Eun-Yeung
authors.initials: EY
authors.lastname: Gong
authors.forename: Eunsook
authors.initials: E
authors.lastname: Park
authors.forename: Hyun Joo
authors.initials: HJ
authors.lastname: Lee
authors.forename: Keesook
authors.initials: K
authors.lastname: Lee
mesh_terms: D000177:Acrosome / Q000201:enzymology; D000251:Adenosine Triphosphatases / Q000032:analysis*; D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008856:Microscopy, Fluorescence; D049294:Phospholipid Transfer Proteins / Q000032:analysis*; D006180:Proton-Translocating ATPases / Q000032:analysis / Q000378:metabolism*; D013087:Spermatids / Q000201:enzymology; D013091:Spermatogenesis / Q000502:physiology*; D013737:Testis / Q000201:enzymology*
chemical_list: D049294:Phospholipid Transfer Proteins; D000251:Adenosine Triphosphatases; D006180:Proton-Translocating ATPases; C539156:Atp8b3 protein, mouse