Inhibition of SAH-hydrolase activity during seed germination leads to deregulation of flowering genes and altered flower morphology in tobacco

• Published in: Molecular genetics and genomics : MGG 2011-03, Vol.285 (3), p.225-236
• Main Authors: Fulneček, Jaroslav, Matyášek, Roman, Votruba, Ivan, Holý, Antonín, Křížová, Kateřina, Kovařík, Aleš
• Format: Article
• Language: English
• Subjects: Adenine - analogs & derivatives; Adenine - toxicity; Adenosylhomocysteinase - antagonists & inhibitors; Adenosylhomocysteinase - metabolism; Animal Genetics and Genomics; Biochemistry; Biomedical and Life Sciences; Blotting, Southern; DEFICIENS/APETALA 3; Deregulation; DHPA; DNA Methylation; DNA Primers - genetics; DNA, Complementary - genetics; Enzymes; Epigenesis, Genetic - drug effects; Epigenesis, Genetic - physiology; Epigenetics; FLORICAULA/LEAFY; Flowers - anatomy & histology; Flowers - physiology; Gene Expression Regulation, Plant - drug effects; Gene Expression Regulation, Plant - genetics; Gene Expression Regulation, Plant - physiology; Genomics; Germination - drug effects; Germination - physiology; GLOBOSA/PISTILLATA; Human Genetics; Life Sciences; MADS box genes; Microbial Genetics and Genomics; Morphology; Nicotiana - enzymology; Nicotiana - physiology; Nicotiana tabacum; Original Paper; plant development; Plant Genetics and Genomics; Plant Proteins - metabolism; PLENA/AGAMOUS; Pollen - physiology; S-adenosyl-l-homocysteine hydrolase inhibitor; Seeds; Statistics, Nonparametric; Tobacco
• ISSN: 1617-4615; 1617-4623
• DOI: 10.1007/s00438-011-0601-8

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.