以陆地棉中35和军棉1号的茎尖为外植体,利用农杆菌介导法将含有拟南芥抗病基因SNC1(sup-pressor of npr1-1,constitutive 1)转入棉花。对外植体培养时期、农杆菌侵染时间和共培养时间进行改良,实验结果表明,在外植体培养1d,菌液侵染20m...以陆地棉中35和军棉1号的茎尖为外植体,利用农杆菌介导法将含有拟南芥抗病基因SNC1(sup-pressor of npr1-1,constitutive 1)转入棉花。对外植体培养时期、农杆菌侵染时间和共培养时间进行改良,实验结果表明,在外植体培养1d,菌液侵染20min,并且共培养保持在2d能够获得较高的遗传转化效率。PCR以及RT-PCR对再生植株T0代和T1代棉花的检测结果表明,SNC1基因已经整合到棉花的基因组中并得到表达。利用浸根法,对T1代转基因棉花接种棉花枯萎病菌强致病力菌株(Fusarium oxysporum f.sp.Vasinfectum),与对照比较,T1代转基因棉花的枯萎病抗性明显提高。展开更多
【目的】棉花抵御外来病原物侵害的途径是多种多样的,研究抗病转基因棉和非转基因棉在组织结构上的抗性差异。【方法】利用茎尖遗传转化获得的转SNC1(suppressor of npr1-1,constitutive)基因棉花"中35"和"军棉1号"...【目的】棉花抵御外来病原物侵害的途径是多种多样的,研究抗病转基因棉和非转基因棉在组织结构上的抗性差异。【方法】利用茎尖遗传转化获得的转SNC1(suppressor of npr1-1,constitutive)基因棉花"中35"和"军棉1号",通过营养钵伤根法对其接种棉花枯萎病菌菌株,借助石蜡切片技术,观察棉株根茎部细胞解剖结构。【结果】抗病转基因棉根茎部胼胝质、侵填体和胶质体形成多于非转基因棉,并且韧皮部细胞排列紧密,规整,细胞间隙小。【结论】组织结构抗性在棉花抵御外来病原物侵害时所起到的至关重要的作用。展开更多
The nucleotide-binding and leucine-rich repeat(NLR)proteins comprise a major class of intracellular immune receptors that are capable of detecting pathogen-derived molecules and activating immunity and cell death in p...The nucleotide-binding and leucine-rich repeat(NLR)proteins comprise a major class of intracellular immune receptors that are capable of detecting pathogen-derived molecules and activating immunity and cell death in plants.The activity of some NLRs,particularly the Toll-like/interleukin-1 receptor(TIR)type,is highly correlated with their nucleocytoplasmic distribution.However,whether and how the nucleocytoplasmic homeostasis of NLRs is coordinated through a bidirectional nuclear shuttling mechanism remains unclear.Here,we identified a nuclear transport receptor,KA120,which is capable of affecting the nucleocytoplasmic distribution of an NLR protein and is essential in preventing its autoactivation.We showed that the ka120 mutant displays an autoimmune phenotype and NLR-induced transcriptome features.Through a targeted genetic screen using an artificial NLR microRNA library,we identified the TIR-NLR gene SNC1 as a genetic interactor of KA120.Loss-of-function snc1 mutations as well as compromising SNC1 protein activities all substantially suppressed ka120-induced autoimmune activation,and the enhanced SNC1 activity upon loss of KA120 functionappeared to occur at the protein level.Overexpression of KA120 efficiently repressed SNC1 activity and led to a nearly complete suppression of the autoimmune phenotype caused by the gain-of-function snc1-1 mutation or SNC1 overexpression in transgenic plants.Further florescence imaging analysis indicated that SNC1 undergoes altered nucleocytoplasmic distribution with significantly reduced nuclear signal when KA120 is constitutively expressed,supporting a role of KA120 in coordinating SNC1 nuclear abundance and activity.Consistently,compromising the SNC1 nuclear level by disrupting the nuclear pore complex could also partially rescue ka120-induced autoimmunity.Collectively,our study demonstrates that KA120 is essential to avoid autoimmune activation in the absence of pathogens and is required to constrain the nuclear activity of SNC1,possibly through coordinating SNC1 nucleocytoplasmic homeostasis as a potential mechanism.展开更多
文摘【目的】棉花抵御外来病原物侵害的途径是多种多样的,研究抗病转基因棉和非转基因棉在组织结构上的抗性差异。【方法】利用茎尖遗传转化获得的转SNC1(suppressor of npr1-1,constitutive)基因棉花"中35"和"军棉1号",通过营养钵伤根法对其接种棉花枯萎病菌菌株,借助石蜡切片技术,观察棉株根茎部细胞解剖结构。【结果】抗病转基因棉根茎部胼胝质、侵填体和胶质体形成多于非转基因棉,并且韧皮部细胞排列紧密,规整,细胞间隙小。【结论】组织结构抗性在棉花抵御外来病原物侵害时所起到的至关重要的作用。
基金X.Shen and X.Shi were supported by Tsinghua-Peking Joint Center tor Life SciencesThis project was supported by the USDA National Institute of Food and Agriculture(HATCH project CA-B-PLB-0243-H)+1 种基金the National Science Foundation(grant MCB-2049931)startup funds from Inno-vative Genomics Institute and University of California Berkeley.
文摘The nucleotide-binding and leucine-rich repeat(NLR)proteins comprise a major class of intracellular immune receptors that are capable of detecting pathogen-derived molecules and activating immunity and cell death in plants.The activity of some NLRs,particularly the Toll-like/interleukin-1 receptor(TIR)type,is highly correlated with their nucleocytoplasmic distribution.However,whether and how the nucleocytoplasmic homeostasis of NLRs is coordinated through a bidirectional nuclear shuttling mechanism remains unclear.Here,we identified a nuclear transport receptor,KA120,which is capable of affecting the nucleocytoplasmic distribution of an NLR protein and is essential in preventing its autoactivation.We showed that the ka120 mutant displays an autoimmune phenotype and NLR-induced transcriptome features.Through a targeted genetic screen using an artificial NLR microRNA library,we identified the TIR-NLR gene SNC1 as a genetic interactor of KA120.Loss-of-function snc1 mutations as well as compromising SNC1 protein activities all substantially suppressed ka120-induced autoimmune activation,and the enhanced SNC1 activity upon loss of KA120 functionappeared to occur at the protein level.Overexpression of KA120 efficiently repressed SNC1 activity and led to a nearly complete suppression of the autoimmune phenotype caused by the gain-of-function snc1-1 mutation or SNC1 overexpression in transgenic plants.Further florescence imaging analysis indicated that SNC1 undergoes altered nucleocytoplasmic distribution with significantly reduced nuclear signal when KA120 is constitutively expressed,supporting a role of KA120 in coordinating SNC1 nuclear abundance and activity.Consistently,compromising the SNC1 nuclear level by disrupting the nuclear pore complex could also partially rescue ka120-induced autoimmunity.Collectively,our study demonstrates that KA120 is essential to avoid autoimmune activation in the absence of pathogens and is required to constrain the nuclear activity of SNC1,possibly through coordinating SNC1 nucleocytoplasmic homeostasis as a potential mechanism.