title: Coronary stem development in wild-type and Tbx1 null mouse hearts.
abstract: BACKGROUND
  Coronary artery (CA) stems connect the ventricular coronary tree with the aorta. Defects in proximal CA patterning are a cause of sudden cardiac death. In mice lacking Tbx1, common arterial trunk is associated with an abnormal trajectory of the proximal left CA. Here we investigate CA stem development in wild-type and Tbx1 null embryos.
  
  
  RESULTS
  Genetic lineage tracing reveals that limited outgrowth of aortic endothelium contributes to proximal CA stems. Immunohistochemistry and fluorescent tracer injections identify a periarterial vascular plexus present at the onset of CA stem development. Transplantation experiments in avian embryos indicate that the periarterial plexus originates in mesenchyme distal to the outflow tract. Tbx1 is required for the patterning but not timing of CA stem development and a Tbx1 reporter allele is expressed in myocardium adjacent to the left but not right CA stem. This expression domain is maintained in Sema3c(-/-) hearts with a common arterial trunk and leftward positioned CA. Ectopic myocardial differentiation is observed on the left side of the Tbx1(-/-) common arterial trunk.
  
  
  CONCLUSIONS
  A periarterial plexus bridges limited outgrowth of the aortic endothelium with the ventricular plexus during CA stem development. Molecular differences associated with left and right CA stems provide new insights into the etiology of CA patterning defects.
authors.affiliation: Aix-Marseille University, CNRS, IBDM UMR 7288, Marseille, France.
authors.forename: Magali
authors.initials: M
authors.lastname: Théveniau-Ruissy
authors.affiliation: Department of Animal Biology, Instituto de Investigación Biomedica de Málaga (IBIMA), Faculty of Science, University of Málaga, Málaga, Spain.|Andalusian Centre for Nanomedicine and Biotechnology (BIONAND), Málaga, Spain.
authors.forename: José-Maria
authors.initials: JM
authors.lastname: Pérez-Pomares
authors.affiliation: Aix-Marseille University, CNRS, IBDM UMR 7288, Marseille, France.
authors.forename: Pauline
authors.initials: P
authors.lastname: Parisot
authors.affiliation: Institute of Genetics and Biophysics, Naples, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Baldini
authors.affiliation: Aix-Marseille University, CNRS, IBDM UMR 7288, Marseille, France.
authors.forename: Lucile
authors.initials: L
authors.lastname: Miquerol
authors.affiliation: Aix-Marseille University, CNRS, IBDM UMR 7288, Marseille, France.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Kelly
mesh_terms: D000818:Animals; D001011:Aorta / Q000196:embryology* / Q000473:pathology; D002642:Chick Embryo; D003331:Coronary Vessels / Q000196:embryology* / Q000473:pathology; D004730:Endothelium, Vascular / Q000196:embryology* / Q000473:pathology; D006321:Heart / Q000196:embryology*; D051379:Mice; D008817:Mice, Mutant Strains; D013234:Stem Cells / Q000378:metabolism* / Q000473:pathology; D020825:T-Box Domain Proteins / Q000172:deficiency*
chemical_list: D020825:T-Box Domain Proteins; C491573:Tbx1 protein, mouse
keywords: Tbx1; coronary arteries; coronary ostia; heart development