title: Endothelium-specific replacement of the connexin43 coding region by a lacZ reporter gene.
abstract: The murine gap junction protein connexin43 (Cx43) is expressed in blood vessels, with vastly different contribution by endothelial and smooth muscle cells. We have used the Cre recombinase under control of TIE2 transcriptional elements to inactivate a floxed Cx43 gene specifically in endothelial cells. Cre-mediated deletion led to replacement of the Cx43 coding region by a lacZ reporter gene. This allowed us to monitor the extent of deletion and to visualize the endothelial expression pattern of Cx43. We found widespread endothelial expression of the Cx43 gene during embryonic development, which became restricted largely to capillaries and small vessels in all adult organs examined. Mice lacking Cx43 in endothelium did not exhibit altered blood pressure, in contrast to mice deficient in Cx40. Our results show that lacZ activation after deletion of the target gene allows us to determine the extent of cell type-specific deletion after phenotypical investigation of the same animal.
authors.affiliation: Institut für Genetik, Universität Bonn, Bonn, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Theis
authors.forename: C
authors.initials: C
authors.lastname: de Wit
authors.forename: T M
authors.initials: TM
authors.lastname: Schlaeger
authors.forename: D
authors.initials: D
authors.lastname: Eckardt
authors.forename: O
authors.initials: O
authors.lastname: Krüger
authors.forename: B
authors.initials: B
authors.lastname: Döring
authors.forename: W
authors.initials: W
authors.lastname: Risau
authors.forename: U
authors.initials: U
authors.lastname: Deutsch
authors.forename: U
authors.initials: U
authors.lastname: Pohl
authors.forename: K
authors.initials: K
authors.lastname: Willecke
mesh_terms: D000818:Animals; D001795:Blood Pressure Determination; D018031:Connexin 43 / Q000235:genetics*; D004247:DNA / Q000032:analysis; D004622:Embryo, Mammalian / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D015870:Gene Expression; D018390:Gene Targeting / Q000379:methods*; D017930:Genes, Reporter; D006801:Humans; D007124:Immunoenzyme Techniques; D019426:Integrases / Q000235:genetics* / Q000378:metabolism; D007763:Lac Operon; D051379:Mice; D008822:Mice, Transgenic; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D012333:RNA, Messenger / Q000096:biosynthesis; D013234:Stem Cells / Q000502:physiology; D014158:Transcription, Genetic; D014764:Viral Proteins; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D018031:Connexin 43; D012333:RNA, Messenger; D014764:Viral Proteins; D004247:DNA; D019001:Nitric Oxide Synthase; C045073:Cre recombinase; D019426:Integrases; D001616:beta-Galactosidase; D019331:NG-Nitroarginine Methyl Ester