本研究从贵州地方粳稻(Oryza sativa ssp.japonica)品种‘黎平杂边禾’甲基磺酸乙酯(EMS)突变体库中筛选获得一份能稳定遗传的矮秆小粒突变体,暂命名为dss1(dwarf and small seed 1)。与野生型相比,dss1表现为植株矮化、株型直立、叶色...本研究从贵州地方粳稻(Oryza sativa ssp.japonica)品种‘黎平杂边禾’甲基磺酸乙酯(EMS)突变体库中筛选获得一份能稳定遗传的矮秆小粒突变体,暂命名为dss1(dwarf and small seed 1)。与野生型相比,dss1表现为植株矮化、株型直立、叶色深绿、籽粒变小、第二节间严重缩短、穗长增加等典型油菜素内酯(BR)缺陷突变体的性状。显微观察结果表明dss1叶鞘表皮细胞的长度变短,可能是突变体第二叶鞘长度比野生型短的原因。对突变体的暗形态建成与BR敏感性研究表明,黑暗条件下突变体表现为去黄化表型,对外源BR敏感。遗传特性分析证明dss1突变体由一个隐性单基因位点控制。利用Mut Map技术将dss1基因定位于3号染色体上,筛选获得一个候选基因,测序结果表明,dss1候选基因为BR合成途径关键酶基因Os DWARF,dss1是由于该基因第5个外显子上第335位的氨基酸由苏氨酸(ACT)突变为异亮氨酸(ATT)所引起的。定位得到的矮化小粒基因DSS1为一个新的Os DWARF等位基因。展开更多
Plant architecture is a vital agronomic trait to control yield in rice(Oryza sativa L.).A dwarf and small seed 1(dss1)mutant were obtained from the ethyl methanesulfonate(EMS)mutagenized progeny of a Guizhou glutinous...Plant architecture is a vital agronomic trait to control yield in rice(Oryza sativa L.).A dwarf and small seed 1(dss1)mutant were obtained from the ethyl methanesulfonate(EMS)mutagenized progeny of a Guizhou glutinous landrace cultivar,Lipingzabianhe.The dss1 mutant displayed phenotypes similar to those of brassinosteroid(BR)deficient mutants,such as dwarfing,dark green and rugose erect leaves,small seeds,and loner neck internode panicles with primary branching.In our previous study,the underlying DSS1 gene was isolated,a novel allele of OsDWARF(OsBR6ox)that encodes a cytochrome P450 protein involved in the BR biosynthetic pathway by MutMap technology.In this work,we confirmed that a Thr335Ile amino acid substitution residing in DSS1/OsDWARF was responsible for the dwarf,panicle architecture,and small seed phenotypes in the dss1 mutants by genetic transformation experiments.The overexpression of OsDWARF in the dss1 mutant background could not only recover dss1 to the normal plant height and panicle architecture but also rescued normal leaf angles,seed size,and leaf color.Thus,the specific mutation in DSS1/OsDWARF influenced plant architecture,seed size,and chlorophyll biosynthesis.展开更多
Timely removal of oxidatively damaged proteins is crit- ical for cells exposed to oxidative stresses; however, cellular mechanism for clearing oxidized proteins is not clear. Our study reveals a novel type of protein ...Timely removal of oxidatively damaged proteins is crit- ical for cells exposed to oxidative stresses; however, cellular mechanism for clearing oxidized proteins is not clear. Our study reveals a novel type of protein modifi- cation that may play a role in targeting oxidized proteins and remove them. In this process, DSS1 （deleted in split hand/split foot 1）, an evolutionally conserved small protein, is conjugated to proteins induced by oxidative stresses in vitro and in vivo, implying oxidized proteins are DSS1 clients. A subsequent ubiquitination targeting DSSl-protein adducts has been observed, suggesting the client proteins are degraded through the ubiquitin- proteasome pathway. The DSS1 attachment to its clients is evidenced to be an enzymatic process modulated by an unidentified ATPase. We name this novel protein modification as DSSylation, in which DSS1 plays as amodifier, whose attachment may render target proteins a signature leading to their subsequent ubiquitination, thereby recruits proteasome to degrade them.展开更多
文摘本研究从贵州地方粳稻(Oryza sativa ssp.japonica)品种‘黎平杂边禾’甲基磺酸乙酯(EMS)突变体库中筛选获得一份能稳定遗传的矮秆小粒突变体,暂命名为dss1(dwarf and small seed 1)。与野生型相比,dss1表现为植株矮化、株型直立、叶色深绿、籽粒变小、第二节间严重缩短、穗长增加等典型油菜素内酯(BR)缺陷突变体的性状。显微观察结果表明dss1叶鞘表皮细胞的长度变短,可能是突变体第二叶鞘长度比野生型短的原因。对突变体的暗形态建成与BR敏感性研究表明,黑暗条件下突变体表现为去黄化表型,对外源BR敏感。遗传特性分析证明dss1突变体由一个隐性单基因位点控制。利用Mut Map技术将dss1基因定位于3号染色体上,筛选获得一个候选基因,测序结果表明,dss1候选基因为BR合成途径关键酶基因Os DWARF,dss1是由于该基因第5个外显子上第335位的氨基酸由苏氨酸(ACT)突变为异亮氨酸(ATT)所引起的。定位得到的矮化小粒基因DSS1为一个新的Os DWARF等位基因。
基金This work was supported by grants from the Genetically Modified Organisms Breeding Major Projects of China(2016ZX08010003)The Science and Technology Foundation of Guizhou Province(20181043)+1 种基金The Science and Technology Cooperation Project of Guizhou Province([2016]7448)Guizhou university talent introduced project(2015[25]).
文摘Plant architecture is a vital agronomic trait to control yield in rice(Oryza sativa L.).A dwarf and small seed 1(dss1)mutant were obtained from the ethyl methanesulfonate(EMS)mutagenized progeny of a Guizhou glutinous landrace cultivar,Lipingzabianhe.The dss1 mutant displayed phenotypes similar to those of brassinosteroid(BR)deficient mutants,such as dwarfing,dark green and rugose erect leaves,small seeds,and loner neck internode panicles with primary branching.In our previous study,the underlying DSS1 gene was isolated,a novel allele of OsDWARF(OsBR6ox)that encodes a cytochrome P450 protein involved in the BR biosynthetic pathway by MutMap technology.In this work,we confirmed that a Thr335Ile amino acid substitution residing in DSS1/OsDWARF was responsible for the dwarf,panicle architecture,and small seed phenotypes in the dss1 mutants by genetic transformation experiments.The overexpression of OsDWARF in the dss1 mutant background could not only recover dss1 to the normal plant height and panicle architecture but also rescued normal leaf angles,seed size,and leaf color.Thus,the specific mutation in DSS1/OsDWARF influenced plant architecture,seed size,and chlorophyll biosynthesis.
文摘Timely removal of oxidatively damaged proteins is crit- ical for cells exposed to oxidative stresses; however, cellular mechanism for clearing oxidized proteins is not clear. Our study reveals a novel type of protein modifi- cation that may play a role in targeting oxidized proteins and remove them. In this process, DSS1 （deleted in split hand/split foot 1）, an evolutionally conserved small protein, is conjugated to proteins induced by oxidative stresses in vitro and in vivo, implying oxidized proteins are DSS1 clients. A subsequent ubiquitination targeting DSSl-protein adducts has been observed, suggesting the client proteins are degraded through the ubiquitin- proteasome pathway. The DSS1 attachment to its clients is evidenced to be an enzymatic process modulated by an unidentified ATPase. We name this novel protein modification as DSSylation, in which DSS1 plays as amodifier, whose attachment may render target proteins a signature leading to their subsequent ubiquitination, thereby recruits proteasome to degrade them.
