title: Esr proteins are secreted by the cells of the embryo surrounding region.
abstract: Three highly homologous Esr genes are expressed specifically in the embryo surrounding region at the micropylar end of the maize endosperm. The proteins belong to a family of small hydrophilic proteins that share a conserved motive with Clv3, the ligand of the receptor-like kinase Clv1. In this study, co-localization of Esr proteins with their mRNAs in the embryo surrounding region was shown with polyclonal antibodies recognizing all three Esr proteins. On a subcellular level the secretion of Esr proteins and their association with the cell wall was shown independently by cell fractionation, immunohistochemistry and transient expression of Gfp fusion proteins. Furthermore, a possible interaction of Esr proteins with a 35 kDa protein present in the lower half of maize kernels was suggested by in vitro affinity chromatography. Therefore Esr proteins share two characteristics with ligands of receptor-like kinases: they are released in the extracellular space and they have the capacity to form protein-protein interactions.
authors.affiliation: Reproduction et Développement des Plantes, UMR 5667 INRA-CNRS-ENSL-UCBL, ENS-Lyon, 46 Allée d'Italie, F-69364 Lyon Cedex 07, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Bonello
authors.forename: Sandrine
authors.initials: S
authors.lastname: Sevilla-Lecoq
authors.forename: Annick
authors.initials: A
authors.lastname: Berne
authors.forename: Maria-Carmen
authors.initials: MC
authors.lastname: Risueño
authors.forename: Christian
authors.initials: C
authors.lastname: Dumas
authors.forename: Peter M
authors.initials: PM
authors.lastname: Rogowsky
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology; D015153:Blotting, Western; D018506:Gene Expression Regulation, Plant; D007150:Immunohistochemistry; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D017386:Sequence Homology, Amino Acid; D003313:Zea mays / Q000166:cytology / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; C108216:Esr protein, Zea mays; D010940:Plant Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger