title: Xenopus Tetraspanin-1 regulates gastrulation movements and neural differentiation in the early Xenopus embryo.
abstract: The tetraspanin family of four-pass transmembrane proteins has been implicated in fundamental biological processes, including cell adhesion, migration, and proliferation. Tetraspanins interact with various transmembrane proteins, establishing a network of large multimolecular complexes that allows specific lateral secondary interactions. Here we report the identification and functional characterization of Xenopus Tetraspanin-1 (xTspan-1). At gastrula and neurula, xTspan-1 is expressed in the dorsal ectoderm and neural plate, respectively, and in the hatching gland, cement gland, and posterior neural tube at tailbud stages. The expression of xTspan-1 in the early embryo is negatively regulated by bone morphogenetic protein (BMP) and stimulated by Notch signals. Microinjection of xTspan-1 mRNA interfered with gastrulation movements and reduced ectodermal cell adhesion in a cadherin-dependent manner. Morpholino knock-down of endogenous xTspan-1 protein revealed a requirement of xTspan-1 for gastrulation movements and primary neurogenesis. Our data suggest that xTspan-1 could act as a molecular link between BMP signalling and the regulation of cellular interactions that are required for gastrulation movements and neural differentiation in the early Xenopus embryo.
authors.affiliation: Max-Planck Institute of Immunobiology, Stübeweg 51, Freiburg D-79108, Germany.
authors.forename: Yukiyo
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Kristina
authors.initials: K
authors.lastname: Grubisic
authors.forename: Michael
authors.initials: M
authors.lastname: Oelgeschläger
mesh_terms: D000818:Animals; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D002448:Cell Adhesion; D002454:Cell Differentiation; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D005775:Gastrula / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D009024:Morphogenesis; D009474:Neurons / Q000502:physiology*; D051880:Receptors, Notch / Q000378:metabolism; D015398:Signal Transduction; D059470:Tetraspanins; D029867:Xenopus Proteins / Q000378:metabolism / Q000502:physiology*; D014982:Xenopus laevis / Q000196:embryology* / Q000378:metabolism
chemical_list: D019485:Bone Morphogenetic Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D051880:Receptors, Notch; D059470:Tetraspanins; D029867:Xenopus Proteins; C064045:delta protein; C520831:tspan1 protein, Xenopus