title: Diverse lectin-binding specificity of four ZP3 glycoprotein isoforms with a discrete isoelectric point in chicken egg coat.
abstract: The vertebrate egg coat corresponding to mammalian zona pellucida is a filamentous matrix composed of highly and heterogeneously glycosylated proteins designated ZP glycoproteins including ZP1 to 4, ZPD and ZPAX, and play important roles in species-specific egg-sperm interactions. Recent advance in structural biology of chicken ZP3 provided new insights into molecular mechanisms of the egg-coat function involving its carbohydrate moieties. In this study, chicken ZP3 was separated into four major and distinct isoforms with different pI in 2D-PAGE. To investigate the meanings of the ZP3 heterogeneity in egg-sperm interactions, we preliminary analyzed glycan diversity on the molecules by using lectin-staining assays. The four major ZP3 isoforms 4-7 (from acidic to basic) were recognized equally with PNA (Galβ1-3GalNAc), but the isoforms 5-7 were recognized dominantly with WGA ((β-GlcNAc)n, clustered Sia), PHA-E (bi- and triantennary N-glycan containing Galβ1-4GlcNAcβ1-2Manα1-6) and RCA I (terminal Galβ1-4GlcNAc), respectively. Despite such sugar chain diversity among the ZP3 isoforms, a partner in the egg coat, ZP1, showed specific binding to each isoform equally. Localization of ZP1 and ZP3 in the egg-coat matrix were also analyzed.
authors: Department of Applied Biological Chemistry, Faculty of Agriculture, Meijo University, Nagoya 468-8502, Japan. hokumura@meijo-u.ac.jp
authors: Hiroki
authors: H
authors: Okumura
authors: Hideaki
authors: H
authors: Fukushima
authors: Masaki
authors: M
authors: Momoda
authors: Yurie
authors: Y
authors: Ima
authors: Tsukasa
authors: T
authors: Matsuda
authors: Minoru
authors: M
authors: Ujita
mesh_terms: D000818:Animals; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000737:chemistry / Q000378:metabolism; D002642:Chick Embryo; D004527:Egg Proteins / Q000097:blood / Q000737:chemistry / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D007526:Isoelectric Point; D037102:Lectins / Q000737:chemistry / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000097:blood / Q000737:chemistry / Q000378:metabolism*; D010063:Ovum / Q000378:metabolism; D020033:Protein Isoforms / Q000097:blood / Q000737:chemistry / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000097:blood / Q000737:chemistry / Q000378:metabolism*; D013084:Sperm-Ovum Interactions; D000072216:Zona Pellucida Glycoproteins
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D004527:Egg Proteins; D037102:Lectins; D008562:Membrane Glycoproteins; D020033:Protein Isoforms; D011956:Receptors, Cell Surface; D000072216:Zona Pellucida Glycoproteins; C016467:Thomsen-Friedenreich antigen