Plant organ size is an important agronomic trait that makes a significant contribution to plant yield.Despite its central importance,the genetic and molecular mechanisms underlying organ size control remain to be full...Plant organ size is an important agronomic trait that makes a significant contribution to plant yield.Despite its central importance,the genetic and molecular mechanisms underlying organ size control remain to be fully clarified.Here,we report that the trithorax group protein ULTRAPETALA1(ULT1)interacts with the TEOSINTE BRANCHED1/CYCLOIDEA/PCF14/15(TCP14/15)transcription factors by antagonizing the LIN-11,ISL-1,and MEC-3(LIM)peptidase DA1,thereby regulating organ size in Arabidopsis.Loss of ULT1 function significantly increases rosette leaf,petal,silique,and seed size,whereas overexpression of ULT1 results in reduced organ size.ULT1 associates with TCP14 and TCP15 to co-regulate cell size by affecting cellular endoreduplication.Transcriptome analysis revealed that ULT1 and TCP14/15 regulate common target genes involved in endoreduplication and leaf development.ULT1 can be recruited by TCP14/15 to promote lysine 4 of histone H3 trimethylation at target genes,activating their expression to determinefinal cell size.Furthermore,we found that ULT1 influences the interaction of DA1 and TCP14/15 and antagonizes the effect of DA1 on TCP14/15 degradation.Collectively,ourfindings reveal a novel epigenetic mechanism underlying the regulation of organ size in Arabidopsis.展开更多
The blue-light receptor cryptochrome 1(CRY1)primarily mediates blue-light inhibition of hypocotyl elongation in Arabidopsis.However,the underlying mechanisms remain largely elusive.We report here that CRY1 inhibits hy...The blue-light receptor cryptochrome 1(CRY1)primarily mediates blue-light inhibition of hypocotyl elongation in Arabidopsis.However,the underlying mechanisms remain largely elusive.We report here that CRY1 inhibits hypocotyl elongation by repressing brassinosteroid(BR)signaling.A genetic interaction assay reveals the negative regulatory effect of CRY1 on the function of BZR1,a core transcription factor in the BR signaling pathway.We demonstrated that CRY1 interacts with the DNA-binding domain of BZR1 to interfere with the DNA-binding ability of BZR1,and represses its transcriptional activity.Furthermore,we found that CRY1 promotes the phosphorylation of BZR1 and inhibits the nuclear accumulation of BZR1.Interestingly,we discovered that CRY1 interacts with the GSK3-like kinase BIN2 and enhances the interaction of BIN2 and BZR1 in a light-dependent manner.Our findings revealed that CRY1 negatively regulates the function of BZR1 through at least two mechanisms:interfering with the DNA-binding ability of BZR1 and promoting the phosphorylation of BZR1.Therefore,we uncover a novel CRY1-BIN2-BZR1 regulatory module that mediates crosstalk between blue light and BR signaling to coordinate plant growth in Arabidopsis.展开更多
Ms2 is an important dominant male-sterile gene in wheat,but the biochemical function of Ms2 and the mechanism by which it causes male sterility remain elusive.Here,we report the molecular basis underlying Ms2-induced ...Ms2 is an important dominant male-sterile gene in wheat,but the biochemical function of Ms2 and the mechanism by which it causes male sterility remain elusive.Here,we report the molecular basis underlying Ms2-induced male sterility in wheat.We found that activated Ms2 specifically reduces the reactive oxygen species(ROS)signals in anthers and thereby induces termination of wheat anther development at an early stage.Furthermore,our results indicate that Ms2 is localized in mitochondria,where it physically interacts with a wheat homolog of ROS modulator 1(TaRomo1).Romo1 positively regulates the ROS levels in humans but has never been studied in plants.We found that single amino acid substitutions in the Ms2 protein that rescue the ms2 male-sterile phenotype abolish the interaction between Ms2 and TaRomo1.Significantly,Ms2 promotes the transition of TaRomo1 proteins from active monomers to inactive oligomers.Taken together,our findings unravel the molecular basis of Ms2-induced male sterility and reveal a regulatory mechanism in which ROS act as essential signals guiding the anther development program in wheat.展开更多
Photoreceptor phytochrome B(phy B)mediates a variety of light responses in plants.To further elucidate the molecular mechanisms of phy B-regulated hypocotyl elongation,we performed firefly luciferase complementation i...Photoreceptor phytochrome B(phy B)mediates a variety of light responses in plants.To further elucidate the molecular mechanisms of phy B-regulated hypocotyl elongation,we performed firefly luciferase complementation imaging(LCI)screening for phy B-interacting transcription factors(TFs).LCI assays showed that phy B possibly interacts with brassinazoleresistant 1(BZR1),BZR2,AUXIN RESPONSE FACTOR 6(ARF6),and several WRKY DNA-binding TFs in a red light-dependent manner.Furthermore,biochemical assays demonstrated that photoexcited phy B specifically interacts with nonphosphorylated BZR1,the physiologically active form of a master TF in brassinosteroid(BR)signaling,and this interaction can be competitively interfered by phytochrome-interacting factor 4.Furthermore,we showed that phy B can directly interact with the DNA-binding domain of BZR1 and affect the enrichment of BZR1 on the chromatin of target genes.Moreover,our genetic evidence and RNA-seq analysis demonstrated that phy B negatively regulates BR signaling.Together,we revealed that photoexcited phy B directly interacts with the TF BZR1 to repress BR signaling in Arabidopsis.展开更多
Improvements in plant architecture,such as reduced plant height under high-density planting,are important for agricultural production.Light and gibberellin(GA)are essential external and internal cues that affect plant...Improvements in plant architecture,such as reduced plant height under high-density planting,are important for agricultural production.Light and gibberellin(GA)are essential external and internal cues that affect plant architecture.In this study,we characterize the direct interaction of distinct receptors that link light and GA signaling in Arabidopsis(Arabidopsis thaliana)and wheat(Triticum aestivum L.).We show that the light receptor CRY1 represses GA signaling through interaction with all five DELLA proteins and promotion of RGA protein accumulation in Arabidopsis.Genetic analysis shows that CRY1-mediated growth repression is achieved by means of the DELLA proteins.Interestingly,we find that CRY1 also directly interacts with the GA receptor GID1 to competitively inhibit the GID1-GAI interaction.We also show that overexpression of TaCRY1a reduces plant height and coleoptile growth in wheat and that TaCRY1a interacts with both TaGID1 and Rht1 to competitively attenuate the TaGID1-Rht1 interaction.Based on these findings,we propose that the photoreceptor CRY1 competitively inhibits the GID1-DELLA interaction,thereby stabilizing DELLA proteins and enhancing their repression of plant growth.展开更多
基金supported by the National Natural Science Foundation of China (31872805)the Fundamental Research Funds for Central NonProfit of the Chinese Academy of Agricultural Sciences (CAASZDRW202109 and Y2023PT20)the Nanfan Special Project of the Chinese Academy of Agricultural Sciences (YBXM15).
文摘Plant organ size is an important agronomic trait that makes a significant contribution to plant yield.Despite its central importance,the genetic and molecular mechanisms underlying organ size control remain to be fully clarified.Here,we report that the trithorax group protein ULTRAPETALA1(ULT1)interacts with the TEOSINTE BRANCHED1/CYCLOIDEA/PCF14/15(TCP14/15)transcription factors by antagonizing the LIN-11,ISL-1,and MEC-3(LIM)peptidase DA1,thereby regulating organ size in Arabidopsis.Loss of ULT1 function significantly increases rosette leaf,petal,silique,and seed size,whereas overexpression of ULT1 results in reduced organ size.ULT1 associates with TCP14 and TCP15 to co-regulate cell size by affecting cellular endoreduplication.Transcriptome analysis revealed that ULT1 and TCP14/15 regulate common target genes involved in endoreduplication and leaf development.ULT1 can be recruited by TCP14/15 to promote lysine 4 of histone H3 trimethylation at target genes,activating their expression to determinefinal cell size.Furthermore,we found that ULT1 influences the interaction of DA1 and TCP14/15 and antagonizes the effect of DA1 on TCP14/15 degradation.Collectively,ourfindings reveal a novel epigenetic mechanism underlying the regulation of organ size in Arabidopsis.
文摘The blue-light receptor cryptochrome 1(CRY1)primarily mediates blue-light inhibition of hypocotyl elongation in Arabidopsis.However,the underlying mechanisms remain largely elusive.We report here that CRY1 inhibits hypocotyl elongation by repressing brassinosteroid(BR)signaling.A genetic interaction assay reveals the negative regulatory effect of CRY1 on the function of BZR1,a core transcription factor in the BR signaling pathway.We demonstrated that CRY1 interacts with the DNA-binding domain of BZR1 to interfere with the DNA-binding ability of BZR1,and represses its transcriptional activity.Furthermore,we found that CRY1 promotes the phosphorylation of BZR1 and inhibits the nuclear accumulation of BZR1.Interestingly,we discovered that CRY1 interacts with the GSK3-like kinase BIN2 and enhances the interaction of BIN2 and BZR1 in a light-dependent manner.Our findings revealed that CRY1 negatively regulates the function of BZR1 through at least two mechanisms:interfering with the DNA-binding ability of BZR1 and promoting the phosphorylation of BZR1.Therefore,we uncover a novel CRY1-BIN2-BZR1 regulatory module that mediates crosstalk between blue light and BR signaling to coordinate plant growth in Arabidopsis.
基金supported by grants from the National Natural Science FoundationofChina(31871623,31991213)the National Key Research andDevelopment Program of China(2016YFD0100302)+1 种基金the Central Public-interest Scientific Institution Basal Research Fund(S2022D02)the Talent Program and Agricultural Science and Technology Innovation Program of CAAS.WethankLingli Zheng and Yuhong Liuforper forming the wheat transformation and planting,and Drs.Guan-Zhu Han and Yun Zhou forthe experimental assistance.
文摘Ms2 is an important dominant male-sterile gene in wheat,but the biochemical function of Ms2 and the mechanism by which it causes male sterility remain elusive.Here,we report the molecular basis underlying Ms2-induced male sterility in wheat.We found that activated Ms2 specifically reduces the reactive oxygen species(ROS)signals in anthers and thereby induces termination of wheat anther development at an early stage.Furthermore,our results indicate that Ms2 is localized in mitochondria,where it physically interacts with a wheat homolog of ROS modulator 1(TaRomo1).Romo1 positively regulates the ROS levels in humans but has never been studied in plants.We found that single amino acid substitutions in the Ms2 protein that rescue the ms2 male-sterile phenotype abolish the interaction between Ms2 and TaRomo1.Significantly,Ms2 promotes the transition of TaRomo1 proteins from active monomers to inactive oligomers.Taken together,our findings unravel the molecular basis of Ms2-induced male sterility and reveal a regulatory mechanism in which ROS act as essential signals guiding the anther development program in wheat.
基金supported by Institute of Crop SciencesChinese Academy of Agricultural Sciences(CAAS)+1 种基金the Agricultural Science and Technology Innovation Program of CAASYouth Talent Plan of CAAS。
文摘Photoreceptor phytochrome B(phy B)mediates a variety of light responses in plants.To further elucidate the molecular mechanisms of phy B-regulated hypocotyl elongation,we performed firefly luciferase complementation imaging(LCI)screening for phy B-interacting transcription factors(TFs).LCI assays showed that phy B possibly interacts with brassinazoleresistant 1(BZR1),BZR2,AUXIN RESPONSE FACTOR 6(ARF6),and several WRKY DNA-binding TFs in a red light-dependent manner.Furthermore,biochemical assays demonstrated that photoexcited phy B specifically interacts with nonphosphorylated BZR1,the physiologically active form of a master TF in brassinosteroid(BR)signaling,and this interaction can be competitively interfered by phytochrome-interacting factor 4.Furthermore,we showed that phy B can directly interact with the DNA-binding domain of BZR1 and affect the enrichment of BZR1 on the chromatin of target genes.Moreover,our genetic evidence and RNA-seq analysis demonstrated that phy B negatively regulates BR signaling.Together,we revealed that photoexcited phy B directly interacts with the TF BZR1 to repress BR signaling in Arabidopsis.
基金This research was supported by the Central Public-interest Scientific Institution Basic Research Fund(S2021ZD02)the Open Project Funding of the State Key Laboratory of Crop Stress Adaptation and Improvement,the National Natural Science Foundation of China(grant nos.31971880 and 31991213)the Agricultural Science and Technology Innovation Program of CAAS.
文摘Improvements in plant architecture,such as reduced plant height under high-density planting,are important for agricultural production.Light and gibberellin(GA)are essential external and internal cues that affect plant architecture.In this study,we characterize the direct interaction of distinct receptors that link light and GA signaling in Arabidopsis(Arabidopsis thaliana)and wheat(Triticum aestivum L.).We show that the light receptor CRY1 represses GA signaling through interaction with all five DELLA proteins and promotion of RGA protein accumulation in Arabidopsis.Genetic analysis shows that CRY1-mediated growth repression is achieved by means of the DELLA proteins.Interestingly,we find that CRY1 also directly interacts with the GA receptor GID1 to competitively inhibit the GID1-GAI interaction.We also show that overexpression of TaCRY1a reduces plant height and coleoptile growth in wheat and that TaCRY1a interacts with both TaGID1 and Rht1 to competitively attenuate the TaGID1-Rht1 interaction.Based on these findings,we propose that the photoreceptor CRY1 competitively inhibits the GID1-DELLA interaction,thereby stabilizing DELLA proteins and enhancing their repression of plant growth.