title: Claudin5 genes encoding tight junction proteins are required for Xenopus heart formation.
abstract: Claudin proteins are the major components of tight junctions connecting adjacent cells, where they regulate a variety of cellular activities. In the present paper we identified two Xenopus claudin5 genes (cldn5a and 5b), which are expressed early in the developing cardiac region. Precocious cldn5 expression was observed in explants of non-heart-forming mesoderm under inhibition of the canonical Wnt pathway. Cardiogenesis was severely perturbed by antisense oligonucleotides against cldn5 or by Cldn5 proteins lacking the cytoplasmic domain. Results of light- and electron-microscopic observations suggested that cldn5a and 5b are required for Xenopus heart tube formation through epithelialization of the precardiac mesoderm.
authors.affiliation: Research Center for Stem Cell Engineering (SCRC), National Institute of Advanced Industrial Science and Technology (AIST), Higashi, Tsukuba-city, Ibaraki 305-3962, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamagishi
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Ito
authors.forename: Takashi
authors.initials: T
authors.lastname: Ariizumi
authors.forename: Shinji
authors.initials: S
authors.lastname: Komazaki
authors.forename: Hiroki
authors.initials: H
authors.lastname: Danno
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Michiue
authors.forename: Makoto
authors.initials: M
authors.lastname: Asashima
mesh_terms: D000818:Animals; D062507:Claudin-5; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D006321:Heart / Q000196:embryology*; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D019108:Tight Junctions / Q000378:metabolism*; D014981:Xenopus / Q000196:embryology / Q000235:genetics* / Q000378:metabolism*; D029867:Xenopus Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
chemical_list: D062507:Claudin-5; C556560:Cldn5 protein, Xenopus; D008565:Membrane Proteins; D029867:Xenopus Proteins