title: DNA methylation is developmentally regulated for genes essential for cardiogenesis.
abstract: BACKGROUND
  DNA methylation is a major epigenetic mechanism altering gene expression in development and disease. However, its role in the regulation of gene expression during heart development is incompletely understood. The aim of this study is to reveal DNA methylation in mouse embryonic hearts and its role in regulating gene expression during heart development.
  
  
  RESULTS
  We performed the genome-wide DNA methylation profiling of mouse embryonic hearts using methyl-sensitive, tiny fragment enrichment/massively parallel sequencing to determine methylation levels at ACGT sites. The results showed that while global methylation of 1.64 million ACGT sites in developing hearts remains stable between embryonic day (E) 11.5 and E14.5, a small fraction (2901) of them exhibit differential methylation. Gene Ontology analysis revealed that these sites are enriched at genes involved in heart development. Quantitative real-time PCR analysis of 350 genes with differential DNA methylation showed that the expression of 181 genes is developmentally regulated, and 79 genes have correlative changes between methylation and expression, including hyaluronan synthase 2 (Has2). Required for heart valve formation, Has2 expression in the developing heart valves is downregulated at E14.5, accompanied with increased DNA methylation in its enhancer. Genetic knockout further showed that the downregulation of Has2 expression is dependent on DNA methyltransferase 3b, which is co-expressed with Has2 in the forming heart valve region, indicating that the DNA methylation change may contribute to the Has2 enhancer's regulating function.
  
  
  CONCLUSIONS
  DNA methylation is developmentally regulated for genes essential to heart development, and abnormal DNA methylation may contribute to congenital heart disease.
authors.affiliation: Division of Hematology, Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (A.A.C., M.L., A.A.M., Y.W., M.S., B.W., J.M.G., D.Z.).
authors.forename: Alyssa A
authors.initials: AA
authors.lastname: Chamberlain
authors.affiliation: Division of Hematology, Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (A.A.C., M.L., A.A.M., Y.W., M.S., B.W., J.M.G., D.Z.).
authors.forename: Mingyan
authors.initials: M
authors.lastname: Lin
authors.affiliation: Division of Hematology, Department of Obstetrics & Gynecology and Women's Health (Maternal & Fetal Medicine), Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (R.L.L.).
authors.forename: Rolanda L
authors.initials: RL
authors.lastname: Lister
authors.affiliation: Division of Hematology, Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (A.A.C., M.L., A.A.M., Y.W., M.S., B.W., J.M.G., D.Z.).
authors.forename: Alex A
authors.initials: AA
authors.lastname: Maslov
authors.affiliation: Division of Hematology, Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (A.A.C., M.L., A.A.M., Y.W., M.S., B.W., J.M.G., D.Z.).
authors.forename: Yidong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Division of Hematology, Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (A.A.C., M.L., A.A.M., Y.W., M.S., B.W., J.M.G., D.Z.).
authors.forename: Masako
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Division of Hematology, Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (A.A.C., M.L., A.A.M., Y.W., M.S., B.W., J.M.G., D.Z.).
authors.forename: Bingruo
authors.initials: B
authors.lastname: Wu
authors.affiliation: Division of Hematology, Department of Medicine, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (J.M.G.) Division of Hematology, Department of Pediatrics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (J.M.G.) Division of Hematology, Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (A.A.C., M.L., A.A.M., Y.W., M.S., B.W., J.M.G., D.Z.).
authors.forename: John M
authors.initials: JM
authors.lastname: Greally
authors.affiliation: Division of Hematology, Department of Neurology, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (D.Z.) Division of Hematology, Department of Neuroscience, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (D.Z.) Division of Hematology, Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (A.A.C., M.L., A.A.M., Y.W., M.S., B.W., J.M.G., D.Z.).
authors.forename: Deyou
authors.initials: D
authors.lastname: Zheng
authors.affiliation: Division of Cardiology, Departments of Medicine, Pediatrics, and Genetics, and Wilf Family Cardiovascular Research Institute, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY (B.Z.) Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (B.Z.).
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
mesh_terms: D000818:Animals; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics / Q000502:physiology; D019175:DNA Methylation / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D050437:Genes, Developmental / Q000502:physiology; D014453:Glucuronosyltransferase / Q000235:genetics / Q000502:physiology; D006321:Heart / Q000196:embryology*; D000076002:Hyaluronan Synthases; D051379:Mice; D008813:Mice, Inbred ICR; D018345:Mice, Knockout; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction; D000097584:DNA Methyltransferase 3B
chemical_list: D004248:DNA (Cytosine-5-)-Methyltransferases; D014453:Glucuronosyltransferase; D000076002:Hyaluronan Synthases; D000097584:DNA Methyltransferase 3B; C491099:Has2 protein, mouse
keywords: DNA methylation; DNA methyltransferase 3b; gene expression; heart development; hyaluronan synthase 2