title: Morphological changes and hypomethylation of DNA in transgenic tobacco expressing antisense RNA of the S-adenosyl-L-homocysteine hydrolase gene.
abstract: S-adenosyl-L-homocysteine hydrolase (SAHH) is a key enzyme in the regulation of intracellular methylation reactions. To investigate the role of SAHH in methylation reactions and morphogenesis in planta, we have made transgenic plants expressing antisense RNA of tobacco SAHH. The transgenic plants displayed distinct morphological changes including a floral homeotic change. We hypothesized that the changes were caused by increased levels of cytokinin. In those transgenic plants, we observed that a repetitive DNA sequence appeared less methylated than controls. We speculated that altered gene expressions by the hypomethylation of DNA might be involved in the changes.
authors.affiliation: Life Science Research Laboratory, Japan Tobacco Inc., Kanagawa, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Tanaka
authors.forename: C
authors.initials: C
authors.lastname: Masuta
authors.forename: K
authors.initials: K
authors.lastname: Uehara
authors.forename: J
authors.initials: J
authors.lastname: Kataoka
authors.forename: A
authors.initials: A
authors.lastname: Koiwai
authors.forename: M
authors.initials: M
authors.lastname: Noma
mesh_terms: D043383:Adenosylhomocysteinase; D019175:DNA Methylation; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D006867:Hydrolases / Q000096:biosynthesis / Q000235:genetics*; D006868:Hydrolysis; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D016372:RNA, Antisense / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000378:metabolism; D018749:RNA, Plant / Q000096:biosynthesis / Q000235:genetics*; D014026:Nicotiana / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development
chemical_list: D016372:RNA, Antisense; D012333:RNA, Messenger; D018749:RNA, Plant; D006867:Hydrolases; D043383:Adenosylhomocysteinase