Over-Expression of Delays Leaf Senescence in Rice ( L.).

Histone deacetylases (HDACs) influence chromatin state and gene expression. Eighteen genes with important biological functions have been identified in rice. In this study, we surveyed the gene presence frequency of all 18 rice genes in 3,010 rice accessions. showed insertion/deletion (InDel) polymorphisms in almost 98.8% accessions but only 1% accessions. InDel polymorphism association analysis showed that accessions with partial deletions in tended to display early leaf senescence. Further transgenic results confirmed that delayed leaf senescence in rice. The over-expression of delayed leaf senescence, and the knock-down of accelerated leaf senescence. Transcriptome analysis showed that photosynthesis and chlorophyll biosynthesis related genes were up-regulated in over-expression lines, while some programmed cell death and disease resistance related genes were down-regulated. Co-expression network analysis with gene expression view revealed that was co-expressed with multiple genes, particularly , which was significantly up-regulated in : lines. InDels in the promoter region of and in the gene region of occurred coincidentally among more than 90% accessions, and we identified multiple W-box motifs at the InDel position of . Over-expression of also delayed leaf senescence in rice. Taken together, our results suggest that both and are involved in regulating the process of leaf senescence in rice.