title: EphA receptor tyrosine kinases interact with co-expressed ephrin-A ligands in cis.
abstract: Eph receptor tyrosine kinases have been implicated in various developmental processes, including axonal guidance, angiogenesis and morphogenesis. In general, Eph receptors and their ligands, ephrins, are reciprocally compartmentalized during embryogenesis. However, they are expressed in an overlapping fashion in some developing neural and non-neural tissues. Results from the overexpression or mutant mice of ephrin ligands in the retino-tectal system suggest that ephrin-As regulate co-expressed EphA receptor activity, but little is known about the molecular mechanisms. Here we show that EphA receptors and co-expressed ephrin-A ligands interact directly in cis via their functional binding domains, and that this interaction does not seem to mediate intracellular signals, but has an inhibitory effect on the trans interaction.
authors.affiliation: Division of Developmental Neurobiology, Kumamoto University Graduate School of Medical Sciences, Honjo 2, Kumamoto 860-0811, Japan.
authors.forename: Yanzhi
authors.initials: Y
authors.lastname: Yin
authors.forename: Yukie
authors.initials: Y
authors.lastname: Yamashita
authors.forename: Hirono
authors.initials: H
authors.lastname: Noda
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Okafuji
authors.forename: Masahiro J
authors.initials: MJ
authors.lastname: Go
authors.forename: Hideaki
authors.initials: H
authors.lastname: Tanaka
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D015153:Blotting, Western / Q000379:methods; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D002645:Chickens; D004622:Embryo, Mammalian; D004625:Embryo, Nonmammalian; D036342:Ephrins / Q000737:chemistry / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007668:Kidney; D008024:Ligands; D051379:Mice; D008817:Mice, Mutant Strains; D008954:Models, Biological; D010766:Phosphorylation; D011485:Protein Binding / Q000187:drug effects / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis; D036082:Receptor, EphA1 / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D014162:Transfection / Q000379:methods
chemical_list: D000911:Antibodies, Monoclonal; D036342:Ephrins; D008024:Ligands; D012333:RNA, Messenger; D036082:Receptor, EphA1