title: Knockdown of SAMS genes encoding S-adenosyl-l-methionine synthetases causes methylation alterations of DNAs and histones and leads to late flowering in rice.
abstract: S-Adenosyl-l-methionine synthetase (SAMS) [EC 2.5.1.6] catalyzes to produce SAM (S-adenosyl-l-methionine), a universal methyl group donor in biochemical reactions in cells. However, less is known how SAMS controls plant development. Here, we demonstrate that OsSAMS1, 2 and 3 are essential for histone H3K4me3 and DNA methylation to regulate gene expression related to flowering in Oryza sativa. RNA interference (RNAi) transgenic rice with downregulated transcripts of OsSAMS1, 2 and 3 showed pleiotropic phenotypes, including dwarfism, reduced fertility, delayed germination, as well as late flowering. Delayed germination was largely rescued by application of SAM in the knockdown lines. Knockdown of OsSAMS1, 2 and 3 led to distinguished late flowering and greatly reduced the expression of the flowering key genes, Early heading date 1 (Ehd1), Hd3a and RFT1 (rice FT-like genes). Moreover, the histone H3K4me3 and symmetric DNA methylation at these genes were greatly reduced. Thus, SAM deficiency suppressing DNA and H3K4me3 transmethylations at flowering key genes led to a late-flowering phenotype in rice. This information could help elucidate the mechanism of epigenetic control flowering transition.
authors.affiliation: Research Center for Molecular and Developmental Biology, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Wenxuan
authors.initials: W
authors.lastname: Li
authors.forename: Yingying
authors.initials: Y
authors.lastname: Han
authors.forename: Feng
authors.initials: F
authors.lastname: Tao
authors.forename: Kang
authors.initials: K
authors.lastname: Chong
mesh_terms: D019175:DNA Methylation / Q000235:genetics; D044127:Epigenesis, Genetic; D035264:Flowers / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D055785:Gene Knockdown Techniques; D005816:Genetic Complementation Test; D058685:Genetic Pleiotropy; D006657:Histones / Q000378:metabolism*; D008716:Methionine Adenosyltransferase / Q000235:genetics* / Q000378:metabolism; D008745:Methylation; D008969:Molecular Sequence Data; D012275:Oryza / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D017440:Photoperiod; D010802:Phylogeny; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D015003:Yeasts / Q000235:genetics / Q000378:metabolism
chemical_list: D006657:Histones; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D008716:Methionine Adenosyltransferase