The phytohormone gibberellin（GA） plays essential roles in plant growth and development. Here,we report that OsINO80, a conserved ATP-dependent chromatin-remodeling factor in rice（Oryza sativa）, functions in both G...The phytohormone gibberellin（GA） plays essential roles in plant growth and development. Here,we report that OsINO80, a conserved ATP-dependent chromatin-remodeling factor in rice（Oryza sativa）, functions in both GA biosynthesis and diverse biological processes. OsINO80-knockdown mutants, derived from either T-DNA insertion or RNA interference, display typical GA-deficient phenotypes, including dwarfism, reduced cell length, late flowering, retarded seed germination and impaired reproductive development. Consistently, transcriptome analyses reveal that OsINO80 knockdown results in downregulation by more than two-fold of over 1,000 genes, including the GA biosynthesis genes CPS_1 and GA_3ox_2, and the dwarf phenotype of OsINO80-knockdown mutants can be rescued by the application of exogenous GA3. Chromatin immunoprecipitation（Ch IP） experiments show that OsINO80 directly binds to the chromatin of CPS1 and GA_3ox_2 loci. Biochemical assays establish that OsINO80 specially interacts with histone variant H_2A.Z and the H_2A.Z enrichments at CPS_1 and GA_3ox_2 are decreased in OsINO80-knockdown mutants. Thus, our study identified a rice chromatin-remodeling factor,OsINO80, and demonstrated that OsINO80 is involved in regulation of the GA biosynthesis pathway and plays critical functions for many aspects of rice plant growth and development.展开更多
NAC transcription factors(TFs)are pivotal in plant immunity against diverse pathogens.Here,we report the functional and regulatory network of MNAC3,a novel NAC TF,in rice immunity.MNAC3,a transcriptional activator,neg...NAC transcription factors(TFs)are pivotal in plant immunity against diverse pathogens.Here,we report the functional and regulatory network of MNAC3,a novel NAC TF,in rice immunity.MNAC3,a transcriptional activator,negatively modulates rice immunity against blast and bacterial leaf blight diseases and pathogen-associated molecular pattern(PAMP)-triggered immune responses.MNAC3 binds to a CACG cis-element and activates the transcription of immune-negative target genes OsINO80,OsJAZ10,and OsJAZ11.The negative function of MNAC3 in rice immunity depends on its transcription of downstream genes such as OsINO80 and OsJAZ10.MNAC3 interacts with immunity-related OsPP2C41(a protein phosphatase),ONAC066(a NAC TF),and OsDjA6(a DnaJ chaperone).ONAC066 and OsPP2C41 attenuate MNAC3 transcriptional activity,while OsDjA6 promotes it.Phosphorylation of MNAC3 at S163 is critical for its negative functions in rice immunity.OsPP2C41,which plays positive roles in rice blast resistance and chitin-triggered immune responses,dephosphorylates MNAC3,suppressing its transcriptional activity on the target genes OsINO80,OsJAZ10,and OsJAZ11 and promoting the translocation of MNAC3 from nucleus to cytoplasm.These results establish a MNAC3-centered regulatory network in which OsPP2C41 dephosphorylates MNAC3,attenuating its transcriptional activity on downstream immune-negative target genes in rice.Together,these findings deepen our understanding of molecular mechanisms in rice immunity and offer a novel strategy for genetic improvement of rice disease resistance.展开更多
基金supported by the National Basic Research Program of China (973 Program, Grants no.2012CB910500)the National Natural Science Foundation of China (31570315, 91519308, and 31371304)
文摘The phytohormone gibberellin（GA） plays essential roles in plant growth and development. Here,we report that OsINO80, a conserved ATP-dependent chromatin-remodeling factor in rice（Oryza sativa）, functions in both GA biosynthesis and diverse biological processes. OsINO80-knockdown mutants, derived from either T-DNA insertion or RNA interference, display typical GA-deficient phenotypes, including dwarfism, reduced cell length, late flowering, retarded seed germination and impaired reproductive development. Consistently, transcriptome analyses reveal that OsINO80 knockdown results in downregulation by more than two-fold of over 1,000 genes, including the GA biosynthesis genes CPS_1 and GA_3ox_2, and the dwarf phenotype of OsINO80-knockdown mutants can be rescued by the application of exogenous GA3. Chromatin immunoprecipitation（Ch IP） experiments show that OsINO80 directly binds to the chromatin of CPS1 and GA_3ox_2 loci. Biochemical assays establish that OsINO80 specially interacts with histone variant H_2A.Z and the H_2A.Z enrichments at CPS_1 and GA_3ox_2 are decreased in OsINO80-knockdown mutants. Thus, our study identified a rice chromatin-remodeling factor,OsINO80, and demonstrated that OsINO80 is involved in regulation of the GA biosynthesis pathway and plays critical functions for many aspects of rice plant growth and development.
基金supported by grants from the National Natural Science Foundation of China(32072403,31871945)the National Key Research and Development Program of China(2016YFD0100600).
文摘NAC transcription factors(TFs)are pivotal in plant immunity against diverse pathogens.Here,we report the functional and regulatory network of MNAC3,a novel NAC TF,in rice immunity.MNAC3,a transcriptional activator,negatively modulates rice immunity against blast and bacterial leaf blight diseases and pathogen-associated molecular pattern(PAMP)-triggered immune responses.MNAC3 binds to a CACG cis-element and activates the transcription of immune-negative target genes OsINO80,OsJAZ10,and OsJAZ11.The negative function of MNAC3 in rice immunity depends on its transcription of downstream genes such as OsINO80 and OsJAZ10.MNAC3 interacts with immunity-related OsPP2C41(a protein phosphatase),ONAC066(a NAC TF),and OsDjA6(a DnaJ chaperone).ONAC066 and OsPP2C41 attenuate MNAC3 transcriptional activity,while OsDjA6 promotes it.Phosphorylation of MNAC3 at S163 is critical for its negative functions in rice immunity.OsPP2C41,which plays positive roles in rice blast resistance and chitin-triggered immune responses,dephosphorylates MNAC3,suppressing its transcriptional activity on the target genes OsINO80,OsJAZ10,and OsJAZ11 and promoting the translocation of MNAC3 from nucleus to cytoplasm.These results establish a MNAC3-centered regulatory network in which OsPP2C41 dephosphorylates MNAC3,attenuating its transcriptional activity on downstream immune-negative target genes in rice.Together,these findings deepen our understanding of molecular mechanisms in rice immunity and offer a novel strategy for genetic improvement of rice disease resistance.
