title: Changes in DNA methylation during somatic embryogenesis in Cucurbita pepo L.
abstract: Three pumpkin embryogenic lines were initiated on wounded zygotic embryos cultured on medium with or without 2,4-dichlorophenoxyacetic acid (2,4-D). Somatic embryo development was controlled by the availability of various compounds in the medium: presence/absence of 2,4-D, nitrogen sources. The highest rate of DNA methylation was in the early embryo stages, predominantly on MSC medium with 2,4-D and on auxin-free medium supplemented with 1.0 m M NH(4)Cl. DNA methylation was correlated with early embryo development in a manner that was not exclusively dependent on the presence/absence of exogenous auxin. DNA methylation decreased during embryo maturation on auxin-free MSC medium and on auxin-free MSC supplemented with 12.3 micro M 5-azacytidine (5-azaC). The embryogenic features of the pumpkin tissue were preserved, even after a 2-month treatment with 5-azaC.
authors.affiliation: Department of Molecular Biology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, 10000 Zagreb, Croatia. dunja@zg.biol.pmf.hr
authors.forename: Dunja
authors.initials: D
authors.lastname: Leljak-Levanić
authors.forename: Natasa
authors.initials: N
authors.lastname: Bauer
authors.forename: Snjezana
authors.initials: S
authors.lastname: Mihaljević
authors.forename: Sibila
authors.initials: S
authors.lastname: Jelaska
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000494:pharmacology; D000643:Ammonium Chloride / Q000494:pharmacology; D001374:Azacitidine / Q000494:pharmacology; D028464:Cucurbita / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*; D003470:Culture Media / Q000494:pharmacology; D019175:DNA Methylation / Q000187:drug effects*; D018744:DNA, Plant / Q000235:genetics / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006540:Herbicides / Q000494:pharmacology; D007210:Indoleacetic Acids / Q000494:pharmacology; D009584:Nitrogen / Q000378:metabolism / Q000494:pharmacology; D009586:Nitrogen Fixation / Q000187:drug effects / Q000502:physiology; D012038:Regeneration / Q000187:drug effects / Q000502:physiology; D012639:Seeds / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*
chemical_list: D003470:Culture Media; D018744:DNA, Plant; D004791:Enzyme Inhibitors; D006540:Herbicides; D007210:Indoleacetic Acids; D000643:Ammonium Chloride; D015084:2,4-Dichlorophenoxyacetic Acid; D001374:Azacitidine; D009584:Nitrogen