Claudin-5 expression in the vasculature of the developing chick embryo.
The claudin family of proteins are integral components of tight junctions and are responsible for determining the ion specificity and permeability of paracellular transport within epithelial and endothelial cell layers. Studies in human, mouse, Xenopus, and zebrafish have shown that only a limited number of claudins are expressed in endothelial cells. Here, we report the expression pattern of Claudin-5 during chick development. Between HH stage 4 and 6 Claudin-5 expression was observed exclusively in extraembryonic tissue. Claudin-5 expression was not observed in the embryo until HH stage 8, coincident with the onset of embryonic vascularization. Claudin-5 expression was maintained in the developing vasculature in the embryonic and extraembryonic tissue throughout organogenesis (HH stage 19-35), including the vasculature of the ectoderm and of organs derived from the mesoderm and endoderm lineages. These data describe a conserved expression pattern for Claudin-5 in the endothelial tight junction barrier and is the first report of the onset of Claudin-5 expression in a vertebrate embryo.
Department of Human Genetics, Montréal, Québec, Canada H3Z 2Z3; The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada H3Z 2Z3.
Michelle M
MM
Collins
Department of Human Genetics, Montréal, Québec, Canada H3Z 2Z3; The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada H3Z 2Z3.
Amanda I
AI
Baumholtz
Department of Human Genetics, Montréal, Québec, Canada H3Z 2Z3; Department of Pediatrics, McGill University, Montréal, Québec, Canada H3Z 2Z3; The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada H3Z 2Z3.
Aimee K
AK
Ryan
D000595:Amino Acid Sequence; D000818:Animals; D002642:Chick Embryo; D062507:Claudin-5 / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D004475:Ectoderm / Q000196:embryology; D047108:Embryonic Development / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D038081:Organogenesis / Q000235:genetics; D010802:Phylogeny; D019108:Tight Junctions / Q000378:metabolism
D062507:Claudin-5; D018076:DNA, Complementary