title: Novel Roles of GATA4/6 in the Postnatal Heart Identified through Temporally Controlled, Cardiomyocyte-Specific Gene Inactivation by Adeno-Associated Virus Delivery of Cre Recombinase.
abstract: GATA4 and GATA6 are central cardiac transcriptional regulators. The postnatal, stage-specific function of the cardiac transcription factors GATA4 and GATA6 have not been evaluated. In part, this is because current Cre-loxP approaches to cardiac gene inactivation require time consuming and costly breeding of Cre-expressing and "floxed" mouse lines, often with limited control of the extent or timing of gene inactivation. We investigated the stage-specific functions of GATA4 and GATA6 in the postnatal heart by using adeno-associated virus serotype 9 to control the timing and extent of gene inactivation by Cre. Systemic delivery of recombinant, adeno-associated virus 9 (AAV9) expressing Cre from the cardiac specific Tnnt2 promoter was well tolerated and selectively and efficiently recombined floxed target genes in cardiomyocytes. AAV9:Tnnt2-Cre efficiently inactivated Gata4 and Gata6. Neonatal Gata4/6 inactivation caused severe, rapidly lethal systolic heart failure. In contrast, Gata4/6 inactivation in adult heart caused only mild systolic dysfunction but severe diastolic dysfunction. Reducing the dose of AAV9:Tnnt2-Cre generated mosaics in which scattered cardiomyocytes lacked Gata4/6. This mosaic knockout revealed that Gata4/6 are required cell autonomously for physiological cardiomyocyte growth. Our results define novel roles of GATA4 and GATA6 in the neonatal and adult heart. Furthermore, our data demonstrate that evaluation of gene function hinges on controlling the timing and extent of gene inactivation. AAV9:Tnnt2-Cre is a powerful tool for controlling these parameters.
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America.
authors.forename: Terence W
authors.initials: TW
authors.lastname: Prendiville
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America; Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
authors.forename: Haidong
authors.initials: H
authors.lastname: Guo
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America.
authors.forename: Pingzhu
authors.initials: P
authors.lastname: Zhou
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Stevens
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America; Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.
authors.forename: Aibin
authors.initials: A
authors.lastname: He
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America.
authors.forename: Nathan
authors.initials: N
authors.lastname: VanDusen
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America.
authors.forename: Jinghai
authors.initials: J
authors.lastname: Chen
authors.affiliation: Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors.forename: Li
authors.initials: L
authors.lastname: Zhong
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America; Harvard Stem Cell Institute, 1350 Massachusetts Ave, Cambridge, Massachusetts, United States of America.
authors.forename: Da-Zhi
authors.initials: DZ
authors.lastname: Wang
authors.affiliation: Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors.forename: Guangping
authors.initials: G
authors.lastname: Gao
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, United States of America; Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors.forename: William T
authors.initials: WT
authors.lastname: Pu
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000229:Dependovirus / Q000235:genetics*; D050991:GATA4 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D050993:GATA6 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D020868:Gene Silencing; D005822:Genetic Vectors; D006321:Heart / Q000254:growth & development* / Q000502:physiology; D054143:Heart Failure, Systolic / Q000235:genetics; D019426:Integrases / Q000008:administration & dosage / Q000235:genetics*; D008822:Mice, Transgenic; D032383:Myocytes, Cardiac / Q000502:physiology*
chemical_list: D050991:GATA4 Transcription Factor; D050993:GATA6 Transcription Factor; C484171:Gata4 protein, mouse; C494760:Gata6 protein, mouse; C045073:Cre recombinase; D019426:Integrases