title: Mouse gridlock: no aortic coarctation or deficiency, but fatal cardiac defects in Hey2 -/- mice.
abstract: Gridlock (grl) is one of the first mutations characterized from the large zebrafish mutagenesis screens, and it results in an arterial (aortic) maturation defect, which was proposed to resemble aortic coarctation, a clinically important human malformation. While the grl mutation appears to be a hypomorph, grl knockdown experiments have shown even stronger effects on arterial development. We have generated a knockout of the murine Hey2 (gridlock) gene to analyze the mammalian phenotype. Surprisingly, Hey2 loss does not affect aortic development, but it instead leads to a massive postnatal cardiac hypertrophy with high lethality during the first 10 days of life. This cardiomyopathy is ameliorated with time in surviving animals that do not appear to be manifestly impaired during adult life. These differences in phenotypes suggest that changes in expression or function of genes during evolution may lead to quite different pathological phenotypes, if impaired.
authors.affiliation: Theodor-Boveri-Institute of the University of Wuerzburg, Physiological Chemistry I, Am Hubland, D-97074 Wuerzburg, Germany. gessler@biozentrum.uni-wuerzburg.de
authors.forename: Manfred
authors.initials: M
authors.lastname: Gessler
authors.forename: Klaus-Peter
authors.initials: KP
authors.lastname: Knobeloch
authors.forename: Armin
authors.initials: A
authors.lastname: Helisch
authors.forename: Kerstin
authors.initials: K
authors.lastname: Amann
authors.forename: Nina
authors.initials: N
authors.lastname: Schumacher
authors.forename: Elvira
authors.initials: E
authors.lastname: Rohde
authors.forename: Andreas
authors.initials: A
authors.lastname: Fischer
authors.forename: Cornelia
authors.initials: C
authors.lastname: Leimeister
mesh_terms: D000818:Animals; D001017:Aortic Coarctation / Q000235:genetics*; D051792:Basic Helix-Loop-Helix Proteins; D005075:Biological Evolution; D024741:Cardiomyopathy, Hypertrophic, Familial / Q000196:embryology / Q000235:genetics* / Q000473:pathology; D015870:Gene Expression; D006801:Humans; D017403:In Situ Hybridization; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D010641:Phenotype; D011506:Proteins / Q000235:genetics*; D014157:Transcription Factors / Q000172:deficiency* / Q000235:genetics* / Q000502:physiology; D015027:Zebrafish / Q000235:genetics; D029961:Zebrafish Proteins
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D011506:Proteins; D014157:Transcription Factors; D029961:Zebrafish Proteins; C405954:hey2 protein, zebrafish