title: Expression of Penaeus monodon ortholog of Niemann-Pick type C-2 in the spermatic tract, and its role in sperm cholesterol removal.
abstract: Protein and lipid composition of sperm plasma membrane are modified as these gametes continue to mature during their transit along the spermatic tract. Our previous study revealed that during its journey through the spermatic duct of the black tiger prawn, Penaeus monodon, sperm cholesterol content decreases through the action of lipid-binding proteins within the luminal environment. In this study, the full cDNA sequence of epididymal secretory protein E1 (HE1), or Niemann-Pick C2 (NPC2), was cloned from P. monodon (termed Pmnpc2), and its conserved cholesterol/lipid-binding domain was characterized. The putative tertiary structure of PmNPC2 showed high similarity with the structure of Bos taurus NPC2. Pmnpc2 is expressed in many tissues, including the spermatic tract (i.e., testis, vas deferens, terminal ampoule) and the female thelycum. In situ hybridization revealed the presence of Pmnpc2 transcripts in the vas deferens, terminal ampoule, and thelycum epithelia, suggesting that PmNPC2 could be secreted into the lumen of the spermatic duct. A recombinant hexahistidine-tagged PmNPC2 (rPmNPC2-6His) was able to bind cholesterol and sperm lipid extracts, while co-incubation of sperm from the vas deferens with rPmNPC2-6His resulted in the depletion of cholesterol from these gametes. Together, these results suggest that PmNPC2 participates in sperm cholesterol efflux during the sperm maturation process in P. monodon. Mol. Reprod. Dev. 83: 259-270, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Mahidol University, Nakhonsawan Campus, Nakhonsawan, Thailand.
authors.forename: Charoonroj
authors.initials: C
authors.lastname: Chotwiwatthanakun
authors.affiliation: Faculty of Science, Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Mahidol University, Bangkok, Thailand.|Faculty of Science, Department of Anatomy, Mahidol University, Bangkok, Thailand.
authors.forename: Jutharat
authors.initials: J
authors.lastname: Sangatit
authors.affiliation: Faculty of Science, Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Mahidol University, Bangkok, Thailand.
authors.forename: Wanida
authors.initials: W
authors.lastname: Santimanawong
authors.affiliation: Faculty of Science, Department of Anatomy, Mahidol University, Bangkok, Thailand.
authors.forename: Piyaporn
authors.initials: P
authors.lastname: Surinlert
authors.affiliation: Shrimp Genetic Improvement Center, Surat Thani, Thailand.
authors.forename: Juthatip
authors.initials: J
authors.lastname: Prommoon
authors.affiliation: Faculty of Science, Department of Anatomy, Mahidol University, Bangkok, Thailand.
authors.forename: Wattana
authors.initials: W
authors.lastname: Weerachatyanukul
authors.affiliation: Faculty of Science, Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Mahidol University, Bangkok, Thailand.|Faculty of Science, Department of Anatomy, Mahidol University, Bangkok, Thailand.|Aquatic Animal Biotechnology Research Center, Prince of Songkla University Surat Thani Campus, Surat Thani, Thailand.
authors.forename: Boonsirm
authors.initials: B
authors.lastname: Withyachumnarnkul
authors.affiliation: Faculty of Science, Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Mahidol University, Bangkok, Thailand.|Faculty of Science, Department of Anatomy, Mahidol University, Bangkok, Thailand.
authors.forename: Rapeepun
authors.initials: R
authors.lastname: Vanichviriyakit
mesh_terms: D000818:Animals; D060829:Arthropod Proteins / Q000096:biosynthesis / Q000235:genetics; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics; D002784:Cholesterol / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D005786:Gene Expression Regulation / Q000502:physiology*; D008297:Male; D033561:Penaeidae / Q000235:genetics / Q000378:metabolism; D013094:Spermatozoa / Q000378:metabolism*
chemical_list: D060829:Arthropod Proteins; D002352:Carrier Proteins; D002784:Cholesterol