The Rpd3 histone deacetylase complex is a multiple-subunit complex that mediates the regulation of chromatin accessibility and gene expression.Sin3,the largest subunit of Rpd3 complex,is conserved in a broad range of ...The Rpd3 histone deacetylase complex is a multiple-subunit complex that mediates the regulation of chromatin accessibility and gene expression.Sin3,the largest subunit of Rpd3 complex,is conserved in a broad range of eukaryotes.Despite being a molecular scaffold for complex assembly,the functional sites and mechanism of action of Sin3 remain unexplored.In this study,we functionally characterized a glutamate residue(E810)in Fg Sin3,the ortholog of yeast Sin3 in Fusarium graminearum(known as wheat scab fungus).Our findings indicate that E810 was important for the functions of Fg Sin3 in regulating vegetative growth,sexual reproduction,wheat infection,and DON biosynthesis.Furthermore,the E810K missense mutation restored the reduced H4 acetylation caused by the deletion of FNG1,the ortholog of the human inhibitor of growth(ING1)gene in F.graminearum.Correspondingly,the defects of the fng1 mutant were also partially rescued by the E810K mutation in Fg Sin3.Sequence alignment and evolutionary analysis revealed that E810 residue is well-conserved in fungi,animals,and plants.Based on Alphafold2 structure modeling,E810 localized on the Fg Rpd3–Fg Sin3 interface for the formation of a hydrogen bond with Fg Rpd3.Mutation of E810 disrupts the hydrogen bond and likely affects the Fg Rpd3–Fg Sin3 interaction.Taken together,E810 of Fg Sin3 is functionally associated with Fng1 in the regulation of H4 acetylation and related biological processes,probably by affecting the assembly of the Rpd3 complex.展开更多
Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F....Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.pseudograminearum infects wheat remains unclear.In this study,we aimed to elucidate these mechanisms by constructing a T-DNA insertion mutant library for the highly virulent strain WZ-8A of F.pseudograminearum.By screening this mutant library,we identified nine independent mutants that displayed impaired pathogenesis in barley leaves.Among these mutants,one possessed a disruption in the gene FpRCO1 that is an ortholog of Saccharomyces cerevisiae RCO1,encoding essential component of the Rpd3S histone deacetylase complex in F.pseudograminearum.To further investigate the role of FpRCO1 in F.pseudograminearum,we employed a split-marker approach to knock out FpRCO1 in F.pseudograminearum WZ-8A.FpRCO1 deletion mutants exhibit reduced vegetative growth,conidium production,and virulence in wheat coleoptiles and barley leaves,whereas the complementary strain restores these phenotypes.Moreover,under stress conditions,the FpRCO1 deletion mutants exhibited increased sensitivity to NaCl,sorbitol,and SDS,but possessed reduced sensitivity to H_(2)O_(2)compared to these characteristics in the wild-type strain.RNA-seq analysis revealed that deletion of FpRCO1 affected gene expression(particularly the downregulation of TRI gene expression),thus resulting in significantly reduced deoxynivalenol(DON)production.In summary,our findings highlight the pivotal role of FpRCO1 in regulating vegetative growth and development,asexual reproduction,DON production,and pathogenicity of F.pseudograminearum.This study provides valuable insights into the molecular mechanisms underlying F.pseudograminearum infection in wheat and may pave the way for the development of novel strategies to combat this devastating disease.展开更多
Arabidopsis thaliana histone deacetylase 1 （AtHD1 or AtHDA19）, a homolog ot yeast RPD3, is a global regulator ot many physiological and developmental processes in plants. In spite of the genetic evidence for a role ...Arabidopsis thaliana histone deacetylase 1 （AtHD1 or AtHDA19）, a homolog ot yeast RPD3, is a global regulator ot many physiological and developmental processes in plants. In spite of the genetic evidence for a role of AtHD1 in plant gene regulation and development, the biochemical and cellular properties ofAtHD 1 are poorly understood. Here we report cellular localization patterns ofAtHD 1 in vivo and histone deacetylase activity in vitro. The transient and stable expression of a green fluorescent protein （GFP）-tagged AtHD1 in onion cells and in roots, seeds and leaves of the transgenic Arabidopsis, respectively, revealed that AtHD1 is localized in the nucleus presumably in the euchromatic regions and excluded from the nucleolus. The localization patterns ofAtHD 1 are different from those of AtHD2 and AtHDA6 that are involved in nucleolus formation and silencing of transgenes and repeated DNA elements, respectively. In addition, a histone deacetylase activity assay showed that the recombinant AtHD 1 produced in bacteria demonstrated a specific histone deacetylase activity in vitro. The data suggest that AtHD 1 is a nuclear protein and possesses histone deacetylase activities responsible for global transcriptional regulation important to plant growth and development.展开更多
基金supported by the grants from the National Natural Science Foundation of China(32102181)the Shaanxi Science Fund for Distinguished Young Scholars,China(2022JC-14)。
文摘The Rpd3 histone deacetylase complex is a multiple-subunit complex that mediates the regulation of chromatin accessibility and gene expression.Sin3,the largest subunit of Rpd3 complex,is conserved in a broad range of eukaryotes.Despite being a molecular scaffold for complex assembly,the functional sites and mechanism of action of Sin3 remain unexplored.In this study,we functionally characterized a glutamate residue(E810)in Fg Sin3,the ortholog of yeast Sin3 in Fusarium graminearum(known as wheat scab fungus).Our findings indicate that E810 was important for the functions of Fg Sin3 in regulating vegetative growth,sexual reproduction,wheat infection,and DON biosynthesis.Furthermore,the E810K missense mutation restored the reduced H4 acetylation caused by the deletion of FNG1,the ortholog of the human inhibitor of growth(ING1)gene in F.graminearum.Correspondingly,the defects of the fng1 mutant were also partially rescued by the E810K mutation in Fg Sin3.Sequence alignment and evolutionary analysis revealed that E810 residue is well-conserved in fungi,animals,and plants.Based on Alphafold2 structure modeling,E810 localized on the Fg Rpd3–Fg Sin3 interface for the formation of a hydrogen bond with Fg Rpd3.Mutation of E810 disrupts the hydrogen bond and likely affects the Fg Rpd3–Fg Sin3 interaction.Taken together,E810 of Fg Sin3 is functionally associated with Fng1 in the regulation of H4 acetylation and related biological processes,probably by affecting the assembly of the Rpd3 complex.
基金supported by grants from the National Natural Science Foundation of China(31901835)the Science and Technology Planning Project of Henan Province of China(212102110145)the International(Regional)Cooperation and Exchange Program of the National Natural Science Foundation of China(31961143018).
文摘Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.pseudograminearum infects wheat remains unclear.In this study,we aimed to elucidate these mechanisms by constructing a T-DNA insertion mutant library for the highly virulent strain WZ-8A of F.pseudograminearum.By screening this mutant library,we identified nine independent mutants that displayed impaired pathogenesis in barley leaves.Among these mutants,one possessed a disruption in the gene FpRCO1 that is an ortholog of Saccharomyces cerevisiae RCO1,encoding essential component of the Rpd3S histone deacetylase complex in F.pseudograminearum.To further investigate the role of FpRCO1 in F.pseudograminearum,we employed a split-marker approach to knock out FpRCO1 in F.pseudograminearum WZ-8A.FpRCO1 deletion mutants exhibit reduced vegetative growth,conidium production,and virulence in wheat coleoptiles and barley leaves,whereas the complementary strain restores these phenotypes.Moreover,under stress conditions,the FpRCO1 deletion mutants exhibited increased sensitivity to NaCl,sorbitol,and SDS,but possessed reduced sensitivity to H_(2)O_(2)compared to these characteristics in the wild-type strain.RNA-seq analysis revealed that deletion of FpRCO1 affected gene expression(particularly the downregulation of TRI gene expression),thus resulting in significantly reduced deoxynivalenol(DON)production.In summary,our findings highlight the pivotal role of FpRCO1 in regulating vegetative growth and development,asexual reproduction,DON production,and pathogenicity of F.pseudograminearum.This study provides valuable insights into the molecular mechanisms underlying F.pseudograminearum infection in wheat and may pave the way for the development of novel strategies to combat this devastating disease.
基金We thank Mary Bryk and Timothy Hall for critical suggestions to improve the manuscript,David Stelly and Keerti Rathore for assistance in GFP localization studies in onion cells,and Stanislav Vitha in the Microscopy and Imaging Center at Texas A&M University for technical support for epifluorescence microscopic image analysis in the transgenic plants.The work is supported by grants from the National Institutes of Health(GM067015)the National Science Foundation Plant Genome Research Program(DBI0077774)to Z J C.
文摘Arabidopsis thaliana histone deacetylase 1 （AtHD1 or AtHDA19）, a homolog ot yeast RPD3, is a global regulator ot many physiological and developmental processes in plants. In spite of the genetic evidence for a role of AtHD1 in plant gene regulation and development, the biochemical and cellular properties ofAtHD 1 are poorly understood. Here we report cellular localization patterns ofAtHD 1 in vivo and histone deacetylase activity in vitro. The transient and stable expression of a green fluorescent protein （GFP）-tagged AtHD1 in onion cells and in roots, seeds and leaves of the transgenic Arabidopsis, respectively, revealed that AtHD1 is localized in the nucleus presumably in the euchromatic regions and excluded from the nucleolus. The localization patterns ofAtHD 1 are different from those of AtHD2 and AtHDA6 that are involved in nucleolus formation and silencing of transgenes and repeated DNA elements, respectively. In addition, a histone deacetylase activity assay showed that the recombinant AtHD 1 produced in bacteria demonstrated a specific histone deacetylase activity in vitro. The data suggest that AtHD 1 is a nuclear protein and possesses histone deacetylase activities responsible for global transcriptional regulation important to plant growth and development.
