title: Inhibition of SAH-hydrolase activity during seed germination leads to deregulation of flowering genes and altered flower morphology in tobacco.
abstract: Developmental processes are closely connected to certain states of epigenetic information which, among others, rely on methylation of chromatin. S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) are key cofactors of enzymes catalyzing DNA and histone methylation. To study the consequences of altered SAH/SAM levels on plant development we applied 9-(S)-(2,3-dihydroxypropyl)-adenine (DHPA), an inhibitor of SAH-hydrolase, on tobacco seeds during a short phase of germination period (6 days). The transient drug treatment induced: (1) dosage-dependent global DNA hypomethylation mitotically transmitted to adult plants; (2) pleiotropic developmental defects including decreased apical dominance, altered leaf and flower symmetry, flower whorl malformations and reduced fertility; (3) dramatic upregulation of floral organ identity genes NTDEF, NTGLO and NAG1 in leaves. We conclude that temporal SAH-hydrolase inhibition deregulated floral genes expression probably via chromatin methylation changes. The data further show that plants might be particularly sensitive to accurate setting of SAH/SAM levels during critical developmental periods.
authors.affiliation: Institute of Biophysics, Academy of Sciences of the Czech Republic, vvi, Kralovopolska 135, 612 65 Brno, Czech Republic. fulnecek@ibp.cz
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Fulneček
authors.forename: Roman
authors.initials: R
authors.lastname: Matyášek
authors.forename: Ivan
authors.initials: I
authors.lastname: Votruba
authors.forename: Antonín
authors.initials: A
authors.lastname: Holý
authors.forename: Kateřina
authors.initials: K
authors.lastname: Křížová
authors.forename: Aleš
authors.initials: A
authors.lastname: Kovařík
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000633:toxicity; D043383:Adenosylhomocysteinase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015139:Blotting, Southern; D019175:DNA Methylation; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D044127:Epigenesis, Genetic / Q000187:drug effects / Q000502:physiology*; D035264:Flowers / Q000033:anatomy & histology* / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D018525:Germination / Q000187:drug effects / Q000502:physiology*; D010940:Plant Proteins / Q000378:metabolism; D011058:Pollen / Q000502:physiology; D018709:Statistics, Nonparametric; D014026:Nicotiana / Q000201:enzymology / Q000502:physiology*
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; C081703:GLO protein, Nicotiana tabacum; D010940:Plant Proteins; C016391:9-(2,3-dihydroxypropyl)adenine; D043383:Adenosylhomocysteinase; D000225:Adenine