植物免疫调控基因RTP5(Resistance to Phytophthora 5)编码一个含WD40结构域的蛋白,该基因负调控植物对疫霉的抗性。为获得沉默马铃薯中RTP5同源基因StRTP5a和StRTP5b的遗传材料,以便进一步探究StRTP5a和StRTP5b基因的生物学功能。以四...植物免疫调控基因RTP5(Resistance to Phytophthora 5)编码一个含WD40结构域的蛋白,该基因负调控植物对疫霉的抗性。为获得沉默马铃薯中RTP5同源基因StRTP5a和StRTP5b的遗传材料,以便进一步探究StRTP5a和StRTP5b基因的生物学功能。以四倍体马铃薯品种‘Désirée’的cDNA为模板,扩增到靶向StRTP5a和StRTP5b基因的DNA片段,通过Gateway技术将目的片段重组至植物表达载体pHellsgate12,构建同步靶向StRTP5a和StRTP5b基因的目的表达载体pHells12-StRTP5a/b i,然后利用根癌农杆菌介导的遗传转化方法将目的表达载体转化至‘Désirée’中。经PCR和qPCR分析后,获得8株2个目的基因同时沉默的马铃薯株系,转化株系中StRTP5a和StRTP5b基因表达量同时降幅最高达70%以上。展开更多
Active DNA demethylation is critical for altering DNA methylation patterns and regulating gene expression.The 5-methylcytosine DNA glycosylase/lyase ROS1 initiates a base-excision repair pathway for active DNA demethy...Active DNA demethylation is critical for altering DNA methylation patterns and regulating gene expression.The 5-methylcytosine DNA glycosylase/lyase ROS1 initiates a base-excision repair pathway for active DNA demethylation and is required for the prevention of DNA hypermethylation at 1000 s of genomic regions in Arabidopsis.How ROS1 is regulated and targeted to specific genomic regions is not well understood.Here,we report the discovery of an Arabidopsis protein complex that contains ROS1,regulates ROS1 gene expression,and likely targets the ROS1 protein to specific genomic regions.ROS1 physically interacts with a WD40 domain protein(RWD40),which in turn interacts with a methyl-DNA binding protein(RMB1)as well as with a zinc finger and homeobox domain protein(RHD1).RMB1 binds to DNA that is methylated in any sequence context,and this binding is necessary for its function in vivo.Loss-of-function mutations in RWD40,RMB1,or RHD1 cause DNA hypermethylation at several tested genomic regions independently of the known ROS1 regulator IDM1.Because the hypermethylated genomic regions include the DNA methylation monitoring sequence in the ROS1 promoter,plants mutated in RWD40,RMB1,or RHD1 show increased ROS1 expression.Importantly,ROS1 binding to the ROS1 promoter requires RWD40,RMB1,and RHD1,suggesting that this complex dictates ROS1 targeting to this locus.Our results demonstrate that ROS1 forms a protein complex with RWD40,RMB1,and RHD1,and that this novel complex regulates active DNA demethylation at several endogenous loci in Arabidopsis.展开更多
文摘植物免疫调控基因RTP5(Resistance to Phytophthora 5)编码一个含WD40结构域的蛋白,该基因负调控植物对疫霉的抗性。为获得沉默马铃薯中RTP5同源基因StRTP5a和StRTP5b的遗传材料,以便进一步探究StRTP5a和StRTP5b基因的生物学功能。以四倍体马铃薯品种‘Désirée’的cDNA为模板,扩增到靶向StRTP5a和StRTP5b基因的DNA片段,通过Gateway技术将目的片段重组至植物表达载体pHellsgate12,构建同步靶向StRTP5a和StRTP5b基因的目的表达载体pHells12-StRTP5a/b i,然后利用根癌农杆菌介导的遗传转化方法将目的表达载体转化至‘Désirée’中。经PCR和qPCR分析后,获得8株2个目的基因同时沉默的马铃薯株系,转化株系中StRTP5a和StRTP5b基因表达量同时降幅最高达70%以上。
基金supported by the Chinese Academy of SciencesNational Nature Science Foundation of China(32002046)Natural Science Foundation of Jiangsu Province(BK20200948)。
文摘Active DNA demethylation is critical for altering DNA methylation patterns and regulating gene expression.The 5-methylcytosine DNA glycosylase/lyase ROS1 initiates a base-excision repair pathway for active DNA demethylation and is required for the prevention of DNA hypermethylation at 1000 s of genomic regions in Arabidopsis.How ROS1 is regulated and targeted to specific genomic regions is not well understood.Here,we report the discovery of an Arabidopsis protein complex that contains ROS1,regulates ROS1 gene expression,and likely targets the ROS1 protein to specific genomic regions.ROS1 physically interacts with a WD40 domain protein(RWD40),which in turn interacts with a methyl-DNA binding protein(RMB1)as well as with a zinc finger and homeobox domain protein(RHD1).RMB1 binds to DNA that is methylated in any sequence context,and this binding is necessary for its function in vivo.Loss-of-function mutations in RWD40,RMB1,or RHD1 cause DNA hypermethylation at several tested genomic regions independently of the known ROS1 regulator IDM1.Because the hypermethylated genomic regions include the DNA methylation monitoring sequence in the ROS1 promoter,plants mutated in RWD40,RMB1,or RHD1 show increased ROS1 expression.Importantly,ROS1 binding to the ROS1 promoter requires RWD40,RMB1,and RHD1,suggesting that this complex dictates ROS1 targeting to this locus.Our results demonstrate that ROS1 forms a protein complex with RWD40,RMB1,and RHD1,and that this novel complex regulates active DNA demethylation at several endogenous loci in Arabidopsis.
