MGOUN3: evidence for chromatin-mediated regulation of FLC expression.
The MGOUN3(MGO3)/BRUSHY1(BRU1)/TONSOKU(TSK) gene of Arabidopsis thaliana encodes a nuclear leucine-glycine-asparagine (LGN) domain protein that may be implicated in chromatin dynamics and genome maintenance. Mutants with defects in MGO3 display a fasciated stem and disorganized meristem structures. The transition to flowering was examined in mgo3 mutants and it was found that, under short days, the mutants flowered significantly earlier than the wild-type plants. Study of flowering-time associated gene expression showed that the floral transition inhibitor gene FLC was under-expressed in the mutant background. Ectopic expression of the flower-specific genes AGAMOUS (AG), PISTILLATA (PI), and SEPALLATA3 (SEP3) in mgo3 vegetative organs was also detected. Western blot and chromatin immunoprecipitation experiments suggested that histone H3 acetylation may be altered in the mgo3 background. Together, these data suggest that MGO3 is required for the correct transition to flowering and that this may be mediated by histone acetylation and associated changes in FLC expression.
Guyomarc'h
Soazig
S
Institut de Biotechnologie des Plantes, UMR CNRS 8618, Bât. 630. Université Paris XI, Orsay, France.
Benhamed
Moussa
M
Lemonnier
Gaëtan
G
Renou
Jean-Pierre
JP
Zhou
Dao-Xiu
DX
Delarue
Marianne
M
D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism* / Q000502:physiology*; D002843:Chromatin / Q000378:metabolism* / Q000502:physiology; D035264:Flowers / Q000254:growth & development*; D015870:Gene Expression; D017343:Genes, Plant; D026161:MADS Domain Proteins / Q000378:metabolism*; D018519:Meristem; D009154:Mutation; D010641:Phenotype; D017440:Photoperiod; D018515:Plant Leaves / Q000378:metabolism; D013997:Time Factors; D002868:Chromosomal Proteins, Non-Histone
D029681:Arabidopsis Proteins; D002843:Chromatin; D026161:MADS Domain Proteins; C418902:At5g10140 protein, Arabidopsis; C487787:AT3G18730 protein, Arabidopsis; D002868:Chromosomal Proteins, Non-Histone