title: Pig sperm membrane microdomains contain a highly glycosylated 15-25-kDa wheat germ agglutinin-binding protein.
abstract: A highly glycosylated protein, which has unique, novel features in localization, structure, and potential function, is found in pig sperm, and named WGA-gp due to its high binding property with wheat germ agglutinin (WGA). WGA-gp is localized mainly in flagella and enriched in membrane microdomains or lipid rafts. It is not detected by ordinary protein staining methods due to a high content of both N- and O-glycans consisting of neutral monosaccharides. Interestingly, WGA-gp may be involved in intracellular Ca(2+) regulation. Treatment of sperm with anti-WGA-gp antibody enhances the amplitude of Ca(2+) oscillation without changing the basal intracellular Ca(2+) concentrations. All these features of WGA-gp, except for different carbohydrate structures occupying most part of the molecules, are similar to those of flagellasialin in sea urchin sperm, which regulates the intracellular Ca(2+) concentration. Presence of carbohydrate-enriched flagellar proteins involved in intracellular Ca(2+) regulation may be a common feature among animal sperm.
authors.affiliation: Bioscience and Biotechnology Center, Nagoya University, Nagoya 464-8601, Japan. wkasekarn@hotmail.com
authors.forename: Waraporn
authors.initials: W
authors.lastname: Kasekarn
authors.forename: Takeru
authors.initials: T
authors.lastname: Kanazawa
authors.forename: Kazuki
authors.initials: K
authors.lastname: Hori
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Tsuchiyama
authors.forename: Xue
authors.initials: X
authors.lastname: Lian
authors.forename: Estelle
authors.initials: E
authors.lastname: Garénaux
authors.forename: Kessiri
authors.initials: K
authors.lastname: Kongmanas
authors.forename: Nongnuj
authors.initials: N
authors.lastname: Tanphaichitr
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yasue
authors.forename: Chihiro
authors.initials: C
authors.lastname: Sato
authors.forename: Ken
authors.initials: K
authors.lastname: Kitajima
mesh_terms: D000818:Animals; D002352:Carrier Proteins; D006023:Glycoproteins / Q000032:analysis / Q000378:metabolism*; D006031:Glycosylation; D008297:Male; D021962:Membrane Microdomains / Q000737:chemistry / Q000378:metabolism*; D013094:Spermatozoa / Q000737:chemistry / Q000378:metabolism*; D034421:Sus scrofa; D014909:Wheat Germ Agglutinins / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D006023:Glycoproteins; D014909:Wheat Germ Agglutinins