The auxin polar transporter,PIN-FORMED 2(PIN2)plays an important role in root development.However,it remains unclear whether PIN2 genes form two Liriodendron species,L.chinense(LcPIN2)and L.tulipifera(LtPIN2),are both...The auxin polar transporter,PIN-FORMED 2(PIN2)plays an important role in root development.However,it remains unclear whether PIN2 genes form two Liriodendron species,L.chinense(LcPIN2)and L.tulipifera(LtPIN2),are both involved in root development and whether and to what extent these two genes diverge in function.Here,we cloned and overexpressed LcPIN2 and LtPIN2 in Arabidopsis thaliana wild-type(WT)and Atpin2 mutant.Phylogenetic and sequence analysis showed a small degree of differentiation between these two Liriodendron PIN2 genes.Tissue-specific gene expression analysis indicated that both Liriodendron PIN2 genes were highly expressed in roots,implying a potential role in root development.Finally,heterologous overexpression of LcPIN2 and LtPIN2 in Arabidopsis both significantly increased the root length compared to wild-type and empty vector.Furthermore,the root length defect in Atpin2 was complemented both by LcPIN2 and LtPIN2.However,heterologous overexpression of LcPIN2 and LtPIN2 cannot rescue the defect in root gravitropism of Atpin2 mutants.Taken together,ourfindings unravel PIN2 genes from the magnoliids plant Liriodendron were functionally conserved with AtPIN2 in the dicotyledonous plant Arabidopsis in regard to the regulation of root length,but not root gravitropism.This study also provides a potential target for genetic improvement of the root system in these valuable forest trees Liriodendron.展开更多
Plant root systems are essential for many physiological processes,including water and nutrient absorption.MADS-box transcription factor(TF)genes have been characterized as the important regulators of root development ...Plant root systems are essential for many physiological processes,including water and nutrient absorption.MADS-box transcription factor(TF)genes have been characterized as the important regulators of root development in plants;however,the underlying mechanism is largely unknown,including chrysanthemum.Here,it was found that the overexpression of CmANR1,a chrysanthemum MADS-box TF gene,promoted both adventitious root(AR)and lateral root(LR)development in chrysanthemum.Whole transcriptome sequencing analysis revealed a series of differentially expressed unigenes(DEGs)in the roots of CmANR1-transgenic chrysanthemum plants compared to wild-type plants.Functional annotation of these DEGs by alignment with Gene Ontology(GO)terms and biochemical pathway Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis indicated that CmANR1 TF exhibited“DNA binding”and“catalytic”activity,as well as participated in“phytohormone signal transduction”.Both chromatin immunoprecipitation–polymerase chain reaction(ChIP-PCR)and gel electrophoresis mobility shift assays(EMSA)indicated the direct binding of CmPIN2 to the recognition site CArG-box motif by CmANR1.Finally,a firefly luciferase imaging assay demonstrated the transcriptional activation of CmPIN2 by CmANR1 in vivo.Overall,our results provide novel insights into the mechanisms of MADS-box TF CmANR1 modulation of both AR and LR development,which occurs by directly regulating auxin transport gene CmPIN2 in chrysanthemum.展开更多
TiO_(2) nanoparticles(nano-TiO_(2))are widely used in the world,and a considerable amount of nano-TiO_(2) is released into the environment,with toxic effects on organisms.In the various species of higher plants,growth...TiO_(2) nanoparticles(nano-TiO_(2))are widely used in the world,and a considerable amount of nano-TiO_(2) is released into the environment,with toxic effects on organisms.In the various species of higher plants,growth,including seed germination,root elongation,and biomass accumulation,is affected by nano-TiO_(2).However,the underlying molecular mechanisms remain to be elucidated.In this study,we observed that nano-TiO_(2) promoted root elongation in a dose-dependent manner.Furthermore,we found that nano-TiO_(2) elevated auxin accumulation in the root tips of the auxin marker lines DII-VENUS and DR5::GUS,and,correspondingly,quantitative real-time PCR analysis revealed that nano-TiO_(2) increased the expression levels of auxin biosynthesis-and transport-related genes.GFP fluorescence observation using transgenic PIN2-GFP indicated that nano-TiO_(2) promoted root growth by inducing PIN2 accumulation.Thus,we propose that nano-TiO_(2) promote root growth in Arabidopsis thaliana by altering the expression levels of auxin biosynthesis-and transport-related genes.展开更多
Inositol polyphosphate 5-phosphatases (5PTases) are enzymes of phosphatidylinositol metabolism that affect various aspects of plant growth and development. Arabidopsis 5PTasel3 regulates auxin homeostasis and hormon...Inositol polyphosphate 5-phosphatases (5PTases) are enzymes of phosphatidylinositol metabolism that affect various aspects of plant growth and development. Arabidopsis 5PTasel3 regulates auxin homeostasis and hormonerelated cotyledon vein development, and here we demonstrate that its knockout mutant 5pt13 has elevated sensitivity to gravistimulation in root gravitropic responses. The altered responses of 5pt13 mutants to 1-N-naphthylphthalamic acid (an auxin transport inhibitor) indicate that 5PTase13 might be involved in the regulation of auxin transport. Indeed, the auxin efflux carrier PIN2 is expressed more broadly under 5PTasel3 deficiency, and observations of the internalization of the membrane-selective dye FM4-64 reveal altered vesicle trafficking in 5pt13 mutants. Compared with wild-type, 5pt13 mutant seedlings are less sensitive to the inhibition by brefeldin A of vesicle cycling, seedling growth, and the intracellular cycling of the PIN1 and PIN2 proteins. Further, auxin redistribution upon gravitropic stimulation is stimulated under 5PTasel3 deficiency. These results suggest that 5PTasel3 may modulate auxin transport by regulating vesicle trafficking and thereby play a role in root gravitropism.展开更多
基金supported by the Youth Foundation of the Natural Science Foundation of Jiangsu Province(BK20210614)the Nature Science Foundation of China(32071784)+1 种基金Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX21_0921).
文摘The auxin polar transporter,PIN-FORMED 2(PIN2)plays an important role in root development.However,it remains unclear whether PIN2 genes form two Liriodendron species,L.chinense(LcPIN2)and L.tulipifera(LtPIN2),are both involved in root development and whether and to what extent these two genes diverge in function.Here,we cloned and overexpressed LcPIN2 and LtPIN2 in Arabidopsis thaliana wild-type(WT)and Atpin2 mutant.Phylogenetic and sequence analysis showed a small degree of differentiation between these two Liriodendron PIN2 genes.Tissue-specific gene expression analysis indicated that both Liriodendron PIN2 genes were highly expressed in roots,implying a potential role in root development.Finally,heterologous overexpression of LcPIN2 and LtPIN2 in Arabidopsis both significantly increased the root length compared to wild-type and empty vector.Furthermore,the root length defect in Atpin2 was complemented both by LcPIN2 and LtPIN2.However,heterologous overexpression of LcPIN2 and LtPIN2 cannot rescue the defect in root gravitropism of Atpin2 mutants.Taken together,ourfindings unravel PIN2 genes from the magnoliids plant Liriodendron were functionally conserved with AtPIN2 in the dicotyledonous plant Arabidopsis in regard to the regulation of root length,but not root gravitropism.This study also provides a potential target for genetic improvement of the root system in these valuable forest trees Liriodendron.
基金This work was supported by grants from the National Natural Science Foundation of China(31601728)Shandong Province(ZR2016CQ13)Young Scientists Funds of Shandong Agricultural University(564024,24024).
文摘Plant root systems are essential for many physiological processes,including water and nutrient absorption.MADS-box transcription factor(TF)genes have been characterized as the important regulators of root development in plants;however,the underlying mechanism is largely unknown,including chrysanthemum.Here,it was found that the overexpression of CmANR1,a chrysanthemum MADS-box TF gene,promoted both adventitious root(AR)and lateral root(LR)development in chrysanthemum.Whole transcriptome sequencing analysis revealed a series of differentially expressed unigenes(DEGs)in the roots of CmANR1-transgenic chrysanthemum plants compared to wild-type plants.Functional annotation of these DEGs by alignment with Gene Ontology(GO)terms and biochemical pathway Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis indicated that CmANR1 TF exhibited“DNA binding”and“catalytic”activity,as well as participated in“phytohormone signal transduction”.Both chromatin immunoprecipitation–polymerase chain reaction(ChIP-PCR)and gel electrophoresis mobility shift assays(EMSA)indicated the direct binding of CmPIN2 to the recognition site CArG-box motif by CmANR1.Finally,a firefly luciferase imaging assay demonstrated the transcriptional activation of CmPIN2 by CmANR1 in vivo.Overall,our results provide novel insights into the mechanisms of MADS-box TF CmANR1 modulation of both AR and LR development,which occurs by directly regulating auxin transport gene CmPIN2 in chrysanthemum.
基金This work is supported by the National Science Foundation of China(No.31970289).
文摘TiO_(2) nanoparticles(nano-TiO_(2))are widely used in the world,and a considerable amount of nano-TiO_(2) is released into the environment,with toxic effects on organisms.In the various species of higher plants,growth,including seed germination,root elongation,and biomass accumulation,is affected by nano-TiO_(2).However,the underlying molecular mechanisms remain to be elucidated.In this study,we observed that nano-TiO_(2) promoted root elongation in a dose-dependent manner.Furthermore,we found that nano-TiO_(2) elevated auxin accumulation in the root tips of the auxin marker lines DII-VENUS and DR5::GUS,and,correspondingly,quantitative real-time PCR analysis revealed that nano-TiO_(2) increased the expression levels of auxin biosynthesis-and transport-related genes.GFP fluorescence observation using transgenic PIN2-GFP indicated that nano-TiO_(2) promoted root growth by inducing PIN2 accumulation.Thus,we propose that nano-TiO_(2) promote root growth in Arabidopsis thaliana by altering the expression levels of auxin biosynthesis-and transport-related genes.
文摘Inositol polyphosphate 5-phosphatases (5PTases) are enzymes of phosphatidylinositol metabolism that affect various aspects of plant growth and development. Arabidopsis 5PTasel3 regulates auxin homeostasis and hormonerelated cotyledon vein development, and here we demonstrate that its knockout mutant 5pt13 has elevated sensitivity to gravistimulation in root gravitropic responses. The altered responses of 5pt13 mutants to 1-N-naphthylphthalamic acid (an auxin transport inhibitor) indicate that 5PTase13 might be involved in the regulation of auxin transport. Indeed, the auxin efflux carrier PIN2 is expressed more broadly under 5PTasel3 deficiency, and observations of the internalization of the membrane-selective dye FM4-64 reveal altered vesicle trafficking in 5pt13 mutants. Compared with wild-type, 5pt13 mutant seedlings are less sensitive to the inhibition by brefeldin A of vesicle cycling, seedling growth, and the intracellular cycling of the PIN1 and PIN2 proteins. Further, auxin redistribution upon gravitropic stimulation is stimulated under 5PTasel3 deficiency. These results suggest that 5PTasel3 may modulate auxin transport by regulating vesicle trafficking and thereby play a role in root gravitropism.