HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 280, Issue 15, 15029-15037, April 15, 2005

This Article Full Text Full Text (PDF) All Versions of this Article: 280/15/15029    most recent M410538200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sakakibara, K. Articles by Fukami, Y. Search for Related Content PubMed PubMed Citation Articles by Sakakibara, K. Articles by Fukami, Y. Social Bookmarking                      What's this?

Molecular Identification and Characterization of Xenopus Egg Uroplakin III, an Egg Raft-associated Transmembrane Protein That Is Tyrosine-phosphorylated upon Fertilization^*

Keiichi Sakakibara, Ken-ichi Sato¶, Ken-ichi Yoshino||**, Noriko Oshiro||, Shino Hirahara, A. K. M. Mahbub Hasan, Tetsushi Iwasaki, Yasushi Ueda, Yasuhiro Iwao, Kazuyoshi Yonezawa||**, and Yasuo Fukami

From the Graduate School of Science and Technology, the Research Center for Environmental Genomics, and the ^||Biosignal Research Center, Kobe University, Nada, Kobe 657-8501, ^**CREST, Japan Science and Technology Agency, Kawaguchi 332-0012, and the Department of Biological Sciences, Faculty of Science, Yamaguchi University, Yamaguchi 753-8512, Japan

Here we describe mass spectrometric identification, molecular cloning, and biochemical characterization of a lipid/membrane raft-associated protein that is tyrosine-phosphorylated upon Xenopus egg fertilization. This protein is homologous to mammalian uroplakin III, a member of the uroplakin family proteins (UPs) that constitute asymmetric unit membranes in the mammalian urothelial tissues, thus termed Xenopus uroplakin III (xUPIII). xUPIII contains N-linked sugars and is highly expressed in Xenopus eggs, ovary, urinary tract, and kidney. In unfertilized eggs, xUPIII is predominantly localized to the lipid/membrane rafts and exposed on the cell surface, as judged by surface biotinylation experiments and indirect immunofluorescent studies. After fertilization or hydrogen peroxide-induced egg activation, xUPIII becomes rapidly phosphorylated on tyrosine residue-249, which locates in the carboxyl-terminal cytoplasmic tail of the molecule. Raft localization and tyrosine phosphorylation of xUPIII can be reconstituted in HEK293 cells by coexpression of xUPIII, and Xenopus c-Src, a tyrosine kinase whose fertilization-induced activation in egg rafts is required for initiation of development. In mammals, UPIII is forming a complex with a tetraspanin molecule uroplakin Ib. As another tetraspanin, CD9, is known to be a critical component for sperm-egg fusion in the mouse, we have assumed that xUPIII is involved in sperm-egg interaction. An antibody against the extracellular domain of xUPIII blocks sperm-egg interaction, as judged by the occurrence of egg activation and first cell cleavage. Thus, xUPIII represents an egg raft-associated protein that is likely involved in sperm-egg interaction as well as subsequent Src-dependent intracellular events of egg activation in Xenopus.

Received for publication, September 13, 2004 , and in revised form, February 3, 2005.

^* This work was funded in part by grants (16022243, 16026224, 16570174) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan (to K. Sato). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

The nucleotide sequence(s) reported in this paper has been submitted to the GenBank^TM/EBI Data Bank with accession number(s) AB122061 and BAC99015

^¶ To whom correspondence should be addressed. Tel.: 81-78-803-5953; Fax: 81-78-803-5951; E-mail: kksato{at}kobe-u.ac.jp.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				D. W. Petcoff, W. L. Holland, and B. J. Stith Lipid levels in sperm, eggs, and during fertilization in Xenopus laevis J. Lipid Res., November 1, 2008; 49(11): 2365 - 2378. [Abstract] [Full Text] [PDF]

				N. Oshiro, R. Takahashi, K.-i. Yoshino, K. Tanimura, A. Nakashima, S. Eguchi, T. Miyamoto, K. Hara, K. Takehana, J. Avruch, et al. The Proline-rich Akt Substrate of 40 kDa (PRAS40) Is a Physiological Substrate of Mammalian Target of Rapamycin Complex 1 J. Biol. Chem., July 13, 2007; 282(28): 20329 - 20339. [Abstract] [Full Text] [PDF]

				A.K.M. Mahbub Hasan, Z. Ou, K. Sakakibara, S. Hirahara, T. Iwasaki, K.-i. Sato, and Y. Fukami Characterization of Xenopus egg membrane microdomains containing uroplakin Ib/III complex: roles of their molecular interactions for subcellular localization and signal transduction. Genes Cells, February 1, 2007; 12(2): 251 - 267. [Abstract] [Full Text] [PDF]

				D. Jenkins, M. Bitner-Glindzicz, S. Malcolm, J. Allison, R. de Bruyn, S. Flanagan, D. F. M. Thomas, R. A. Belk, S. A. Feather, C. Bingham, et al. Mutation analyses of Uroplakin II in children with renal tract malformations Nephrol. Dial. Transplant., December 1, 2006; 21(12): 3415 - 3421. [Abstract] [Full Text] [PDF]

				L. Meng, J. Luo, C. Li, and W. H Kinsey Role of Src homology 2 domain-mediated PTK signaling in mouse zygotic development. Reproduction, September 1, 2006; 132(3): 413 - 421. [Abstract] [Full Text] [PDF]