RRC ID 19626
著者 Yamatoya K, Yoshida K, Ito C, Maekawa M, Yanagida M, Takamori K, Ogawa H, Araki Y, Miyado K, Toyama Y, Toshimori K.
タイトル Equatorin: identification and characterization of the epitope of the MN9 antibody in the mouse.
ジャーナル Biol Reprod
Abstract Equatorin (MN9 antigenic molecule) is a widely distributed acrosomal protein in mammalian sperm. During the acrosome reaction, some amount of equatorin translocates to the plasma membrane, covering the equatorial region. From the results of studies of both in vitro and in vivo fertilization inhibition using the MN9 antibody, equatorin has been suggested to be involved in fusion with the oolemma. In the present study, we cloned equatorin and, using mass spectrometry and carbohydrate staining, found it to be a highly glycosylated protein. Equatorin is a sperm-specific type 1 transmembrane protein, and glycosidase treatment and recombinant protein assays verified that it is an N,O-sialoglycoprotein. In addition, the gamete interaction-related domain recognized by the MN9 antibody is posttranslationally modified. The modified domain was identified near threonine 138, which was most likely to be O-glycosylated when analyzed by amino acid substitution, dephosphorylation, and O-glycosylation inhibitor assays. Immunogold electron microscopy localized the equatorin N-terminus, where the MN9 epitope is present, on the acrosomal membrane facing the acrosomal lumen. These biochemical properties and the localization of equatorin are important for further analysis of the translocation mechanism leading to gamete interaction.
巻・号 81(5)
ページ 889-97
公開日 2009-11-1
DOI 10.1095/biolreprod.109.077438
PII biolreprod.109.077438
PMID 19605790
MeSH Amino Acid Sequence Animals Antigens / analysis* Antigens / metabolism Blotting, Western Cell Line Cells, Cultured Cloning, Molecular Electrophoretic Mobility Shift Assay Epididymis / metabolism Epitopes / analysis* Male Mass Spectrometry Mice Mice, Inbred ICR Microscopy, Fluorescence Microscopy, Immunoelectron Molecular Sequence Data RNA, Messenger / metabolism Reverse Transcriptase Polymerase Chain Reaction Testis / metabolism
IF 3.322
引用数 21
WOS 分野 REPRODUCTIVE BIOLOGY
リソース情報
ヒト・動物細胞 293T(RCB2202)