SWI/SNF chromatin remodelers are evolutionarily conserved multiprotein complexes that use the energy of ATP hydrolysis to change chromatin structure.A characteristic feature of SWI/SNF remodelers is the occurrence in ...SWI/SNF chromatin remodelers are evolutionarily conserved multiprotein complexes that use the energy of ATP hydrolysis to change chromatin structure.A characteristic feature of SWI/SNF remodelers is the occurrence in both the catalytic ATPase subunit and some auxiliary subunits,of bromodomains,the protein motifs capable of binding acetylated histones.Here,we report that the Arabidopsis bromodomaincontaining proteins BRD1,BRD2,and BRD13 are likely true SWI/SNF subunits that interact with the core SWI/SNF components SWI3C and SWP73B.Loss of function of each single BRD protein caused early flowering but had a negligible effect on other developmental pathways.By contrast,a brd triple mutation(brdx3)led to more pronounced developmental abnormalities,indicating functional redundancy among the BRD proteins.The brdx3 phenotypes,including hypersensitivity to abscisic acid and the gibberellin biosynthesis inhibitor paclobutrazol,resembled those of swi/snf mutants.Furthermore,the BRM protein level and occupancy at the direct target loci SCL3,ABI5,and SVP were reduced in the brdx3 mutant background.Finally,a brdx3 brm-3 quadruple mutant,in which SWI/SNF complexes were devoid of all constituent bromodomains,phenocopied a loss-of-function mutation in BRM.Taken together,our results demonstrate the relevance of BRDs as SWI/SNF subunits and suggest their cooperation with the bromodomain of BRM ATPase.展开更多
基金supported by grants from National Science Centre project nos.2014/15/N/NZ2/00396 to K.J.,2014/13/B/NZ1/00967 to A.J.,and 2017/26/E/NZ2/00899 to R.A.sponsored in part by the Center for Preclinical Research and Technology(CePT)+1 种基金a project co-sponsored by the European Regional Development Fund and Innovative EconomyThe National Cohesion Strategy of Poland.
文摘SWI/SNF chromatin remodelers are evolutionarily conserved multiprotein complexes that use the energy of ATP hydrolysis to change chromatin structure.A characteristic feature of SWI/SNF remodelers is the occurrence in both the catalytic ATPase subunit and some auxiliary subunits,of bromodomains,the protein motifs capable of binding acetylated histones.Here,we report that the Arabidopsis bromodomaincontaining proteins BRD1,BRD2,and BRD13 are likely true SWI/SNF subunits that interact with the core SWI/SNF components SWI3C and SWP73B.Loss of function of each single BRD protein caused early flowering but had a negligible effect on other developmental pathways.By contrast,a brd triple mutation(brdx3)led to more pronounced developmental abnormalities,indicating functional redundancy among the BRD proteins.The brdx3 phenotypes,including hypersensitivity to abscisic acid and the gibberellin biosynthesis inhibitor paclobutrazol,resembled those of swi/snf mutants.Furthermore,the BRM protein level and occupancy at the direct target loci SCL3,ABI5,and SVP were reduced in the brdx3 mutant background.Finally,a brdx3 brm-3 quadruple mutant,in which SWI/SNF complexes were devoid of all constituent bromodomains,phenocopied a loss-of-function mutation in BRM.Taken together,our results demonstrate the relevance of BRDs as SWI/SNF subunits and suggest their cooperation with the bromodomain of BRM ATPase.
