Dofs(DNA-binding with one zinc finger proteins)是植物特有的转录因子家族。Dof蛋白参与许多生物过程,如植物激素的产生,种子发育和环境适应。Dof蛋白已经在多种植物中被鉴定,但在辣椒中尚未开展类似的研究。我们在辣椒中鉴定出了33...Dofs(DNA-binding with one zinc finger proteins)是植物特有的转录因子家族。Dof蛋白参与许多生物过程,如植物激素的产生,种子发育和环境适应。Dof蛋白已经在多种植物中被鉴定,但在辣椒中尚未开展类似的研究。我们在辣椒中鉴定出了33个可能的Dof基因(CaDofs)。为了了解CaDof基因的特征,我们分析了其系统进化关系、蛋白质基序和进化历史。我们将含有25个基序且分布在8条染色体上的33个CaDof基因分成4个族。我们发现CaDof基因的扩张可追溯到最近的复制事件。茄科种系形成之前,片段复制在CaDof家族基因中占主导地位。通过RNA-seq分析获得了CaDof基因表达谱,发现在对包括两种TMV菌株,辣椒斑驳病毒和辣椒疫霉菌的生物胁迫响应过程中,Ca Dof家族基因表现出了时间和病原特异性变化,这表明CaDof基因的功能具有多样性。这些结果不仅为研究Dof基因在生物胁迫中的响应提供有价值的信息,同时也有助于更好地理解Dof基因在辣椒和其他物种中的多重功能。展开更多
Pathogen effectors target diverse subcellular organelles to manipulate the plant immune system.Although the nucleolus has emerged as a stress marker and several effectors are localized in the nucleolus,the roles of nu...Pathogen effectors target diverse subcellular organelles to manipulate the plant immune system.Although the nucleolus has emerged as a stress marker and several effectors are localized in the nucleolus,the roles of nucleolar-targeted effectors remain elusive.In this study,we showed that Phytophthora infestans infection of Nicotiana benthamiana results in nucleolar inflation during the transition from the biotrophic to the necrotrophic phase.Multiple P.infestans effectors were localized in the nucleolus:Pi23226 induced cell death in N.benthamiana and nucleolar inflation similar to that observed in the necrotrophic stage of infection,whereas its homolog Pi23015 and a deletion mutant(Pi23226DC)did not induce cell death or affect nucleolar size.RNA immunoprecipitation and individual-nucleotide-resolution UV crosslinking and immunoprecipitation sequencing analysis indicated that Pi23226 bound to the 30 end of 25S rRNA precursors,resulting in accumulation of unprocessed 27S pre-rRNAs.The nucleolar stress marker NAC082 was strongly upregulated under Pi23226-expressing conditions.Pi23226 subsequently inhibited global protein translation in host cells by interacting with ribosomes.Pi23226 enhanced P.infestans pathogenicity,indicating that Pi23226-induced ribosome malfunction and cell death were beneficial for pathogenesis in the host.Our results provide evidence for the molecular mechanism underlying RNA-binding effector activity in host ribosome biogenesis and lead to new insights into the nucleolar action of effectors in pathogenesis.展开更多
文摘Dofs(DNA-binding with one zinc finger proteins)是植物特有的转录因子家族。Dof蛋白参与许多生物过程,如植物激素的产生,种子发育和环境适应。Dof蛋白已经在多种植物中被鉴定,但在辣椒中尚未开展类似的研究。我们在辣椒中鉴定出了33个可能的Dof基因(CaDofs)。为了了解CaDof基因的特征,我们分析了其系统进化关系、蛋白质基序和进化历史。我们将含有25个基序且分布在8条染色体上的33个CaDof基因分成4个族。我们发现CaDof基因的扩张可追溯到最近的复制事件。茄科种系形成之前,片段复制在CaDof家族基因中占主导地位。通过RNA-seq分析获得了CaDof基因表达谱,发现在对包括两种TMV菌株,辣椒斑驳病毒和辣椒疫霉菌的生物胁迫响应过程中,Ca Dof家族基因表现出了时间和病原特异性变化,这表明CaDof基因的功能具有多样性。这些结果不仅为研究Dof基因在生物胁迫中的响应提供有价值的信息,同时也有助于更好地理解Dof基因在辣椒和其他物种中的多重功能。
基金supported by National Research Foundation of Korea(NRF)grants funded by the Korean government(MSIT)(NRF-2018R1A5A1023599[SRC],NRF-2021R1A2B5B03001613,and NRF-2019R1C1C1008698).
文摘Pathogen effectors target diverse subcellular organelles to manipulate the plant immune system.Although the nucleolus has emerged as a stress marker and several effectors are localized in the nucleolus,the roles of nucleolar-targeted effectors remain elusive.In this study,we showed that Phytophthora infestans infection of Nicotiana benthamiana results in nucleolar inflation during the transition from the biotrophic to the necrotrophic phase.Multiple P.infestans effectors were localized in the nucleolus:Pi23226 induced cell death in N.benthamiana and nucleolar inflation similar to that observed in the necrotrophic stage of infection,whereas its homolog Pi23015 and a deletion mutant(Pi23226DC)did not induce cell death or affect nucleolar size.RNA immunoprecipitation and individual-nucleotide-resolution UV crosslinking and immunoprecipitation sequencing analysis indicated that Pi23226 bound to the 30 end of 25S rRNA precursors,resulting in accumulation of unprocessed 27S pre-rRNAs.The nucleolar stress marker NAC082 was strongly upregulated under Pi23226-expressing conditions.Pi23226 subsequently inhibited global protein translation in host cells by interacting with ribosomes.Pi23226 enhanced P.infestans pathogenicity,indicating that Pi23226-induced ribosome malfunction and cell death were beneficial for pathogenesis in the host.Our results provide evidence for the molecular mechanism underlying RNA-binding effector activity in host ribosome biogenesis and lead to new insights into the nucleolar action of effectors in pathogenesis.