CHD3 chromatin-remodeling factor PICKLE regulates floral transition partially via modulating LEAFY expression at the chromatin level in Arabidopsis  

作　　者：Xing Fu Chaonan Li Qing Liang Yangyang Zhou Hang He Liu-Min Fan 

机构地区：[1]State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China

出　　处：《Science China(Life Sciences)》2016年第5期516-528,共13页中国科学（生命科学英文版）

摘　　要：PICKLE(PKL), a putative CHD3 chromatin remodeling factor, has been suggested to be involved in multiple processes in Arabidopsis. Here, we confirmed the late-flowering phenotype caused by pkl mutation with pkl mutants in two different ecotypes, and investigated the possible mechanisms that account for PKL regulation of flowering time. Quantitative RT-PCR and RNA-seq assays showed that expression of the LEAFY gene(LFY) and a number of LFY-regulated floral homeotic genes were down-regulated in seedlings of the pkl mutants. As predicted, overexpression of LFY restored normal flowering time of pkl mutants. Our results suggest that PKL may be involved in regulating flowering time via LFY expression. To uncover the underlying mechanism, Ch IP-PCR using anti-PKL was performed on materials from three developmental stages of seedlings. Our results showed that PKL associated with the genomic sequences of LFY, particularly at 10-day and 25-day after germination. We also showed that loss of PKL affected H3K27me3 level at the promoter of LFY. Taken together, our data suggest that transcriptional regulation of LFY at the chromatin level by PKL may at least partially account for the late-flowering phenotype of pkl mutants.PICKLE （PKL）, a putative CHD3 chromatin remodeling factor, has been suggested to be involved in multiple processes in Ar- abidopsis. Here, we confirmed the late-flowering phenotype caused by pkl mutation with pkl mutants in two different ecotypes, and investigated the possible mechanisms that account for PKL regulation of flowering time. Quantitative RT-PCR and RNA-seq assays showed that expression of the LEAFY gene （LFY） and a number of LFY-regulated floral homeotic genes were down-regulated in seedlings of the pkl mutants. As predicted, overexpression of LFY restored normal flowering time of pkl mutants. Our results suggest that PKL may be involved in regulating flowering time via LFY expression. To uncover the un- derlying mechanism, ChIP-PCR using anti-PKL was performed on materials from three developmental stages of seedlings. Our results showed that PKL associated with the genomic sequences of LFY, particularly at 10-day and 25-day after germina- tion. We also showed that loss of PKL affected H3K27me3 level at the promoter of LFY. Taken together, our data suggest that transcriptional regulation of LFY at the chromatin level by PKL may at least partially account for the late-flowering phenotype of pkl mutants.

关 键 词：chromatin-remodeling factor PICKLE floral transition LEAFY ARABIDOPSIS 

分 类 号：Q943.2[生物学—植物学]