title: Effects of scrotal heating on sperm surface protein PH-20 expression in sheep.
abstract: Sperm surface protein PH-20 expression was studied during spermatogenesis in pubertal and adult sheep, using molecular and histological methods. The effects of 24 hr of insulation raising scrotal temperatures to 39 degrees C on PH-20 expression in ejaculated sheep sperm were also determined. A 282 nt cDNA fragment of ovine PH-20 was identified in total RNA extracts of sheep testes, which exhibited 76% identity at the nucleotide level with the equivalent region of the human sequence. Ovine PH-20 mRNA and immunoreactivity were identified only in adult ram testis and not in peri-pubertal ram testis tubules lacking round spermatids, nor in adult sheep brain, pituitary, heart, spleen, lung, liver, kidney, epididymis, or ovary. Ovine PH-20 protein was distributed predominantly on the postacrosomal membrane and was also present on the anterior membrane of the sperm head in fresh, unheated sheep semen. Scrotal heating caused a significant, transient decrease in the percentage of PH-20 immunoreactive sperm, but did not change the pattern of PH-20 staining on the sperm head. The results strongly suggest that ovine PH-20 is postmeiotically expressed in haploid germ cells in sheep testis and is arrayed on the membrane of the mature ovine spermatozoon. Scrotal heating appears to have few effects on PH-20 expression and distribution on ejaculated sperm.
authors.affiliation: Department of Anatomy and Structural Biology, Otago School of Medical Science, University of Otago, Dunedin, New Zealand. jean.fleming@stonebow.otago.ac.nz
authors.forename: Jean S
authors.initials: JS
authors.lastname: Fleming
authors.forename: Fu
authors.initials: F
authors.lastname: Yu
authors.forename: Robin M
authors.initials: RM
authors.lastname: McDonald
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Meyers
authors.forename: Grant W
authors.initials: GW
authors.lastname: Montgomery
authors.forename: John F
authors.initials: JF
authors.lastname: Smith
authors.forename: Helen D
authors.initials: HD
authors.lastname: Nicholson
mesh_terms: D000375:Aging / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D015815:Cell Adhesion Molecules / Q000235:genetics* / Q000378:metabolism*; D004542:Ejaculation; D005786:Gene Expression Regulation; D006358:Hot Temperature; D006821:Hyaluronoglucosaminidase; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012611:Scrotum / Q000502:physiology*; D012671:Seminiferous Tubules / Q000378:metabolism; D016415:Sequence Alignment; D012756:Sheep; D013091:Spermatogenesis / Q000235:genetics; D013094:Spermatozoa / Q000378:metabolism*; D013737:Testis / Q000166:cytology / Q000378:metabolism; D014020:Tissue Extracts
chemical_list: D015815:Cell Adhesion Molecules; D012333:RNA, Messenger; D014020:Tissue Extracts; D006821:Hyaluronoglucosaminidase; C066852:hyaluronidase PH-20