Auxin plays a critical role in lateral root(LR)formation.The signaling module composed of auxin-response factors(ARFs)and lateral organ boundaries domain transcription factors mediates auxin signaling to control almos...Auxin plays a critical role in lateral root(LR)formation.The signaling module composed of auxin-response factors(ARFs)and lateral organ boundaries domain transcription factors mediates auxin signaling to control almost every stage of LR development.Here,we show that auxin-induced degradation of the APETALA2/Ethylene Responsive Factor(AP2/ERF)transcription factor ERF13,dependent on MITOGENACTIVATED PROTEIN KINASE MPK14-mediated phosphorylation,plays an essential role in LR development.Overexpression of ERF13 results in restricted passage of the LR primordia through the endodermal layer,greatly reducing LR emergence,whereas the erf13 mutants showed an increase in emerged LR.ERF13 inhibits the expression of 3-ketoacyl-CoA synthase16(KCS16),which encodes a fatty acid elongase involved in very-long-chain fatty acid(VLCFA)biosynthesis.Overexpression of KCS16 or exogenous VLCFA treatment rescues the LR emergence defects in ERF13 overexpression lines,indicating a role downstream of the auxin-MPK14-ERF13 signaling module.Collectively,our study uncovers a novel molecular mechanism by which MPK14-mediated auxin signaling modulates LR development via ERF13-regulated VLCFA biosynthesis.展开更多
[Objective]The aim was to research the function of AtGEF1 in Rac/Rop GTPses mediate auxin signal passway.[Method]Using the transgenic plants of AtGEF1 promotor fused with GUS reporter gene and the over-expression plan...[Objective]The aim was to research the function of AtGEF1 in Rac/Rop GTPses mediate auxin signal passway.[Method]Using the transgenic plants of AtGEF1 promotor fused with GUS reporter gene and the over-expression plants of Rac/Rop GEF1 under the control of 35S promoter as materials,which were constructed from our lab,the expression pattern of GEF1 was analyzed by GUS assay using histochemical staining,and the development of seedling roots of over-expression plant of GEF1 was observed.[Result]GEF1 expression was mainly detected in root meristem,root vascular tissue,lateral roots and root hair.Furthermore,the expression level of GEF1 was highly increased with the induction of NAA.Over-expression of GEF1 was observed to enhance lateral root formation.[Conclusion]GEF1 may be involved in the regulation of development of root and root hair,and it may have redundant function in the control of lateral root development.展开更多
Brassinosteroids （BRs） are natural plant hormones critical for growth and development. BR-deficient or signaling mutants show significantly shortened root phenotypes. But for a long time, it was thought that these p...Brassinosteroids （BRs） are natural plant hormones critical for growth and development. BR-deficient or signaling mutants show significantly shortened root phenotypes. But for a long time, it was thought that these phenotypes were solely caused by reduced root cell elongation in the mutants. Functions of BRs in regulating root development have been largely neglected. Recent detailed analyses, however, revealed that BRs are not only involved in root cell elongation but are also involved in many aspects of root development, such as maintenance of meristem size, root hair formation, lateral root initiation, gravitropic response, mycorrhiza formation, and nodulation in legume species. In this review, current findings on the functions of BRs in mediating root growth, development, and symbiosis are discussed.展开更多
During plant development, the frequency and context of cell division must be controlled, and cells must differentiate properly to perform their mature functions. In addition, stem cell niches need to be maintained as ...During plant development, the frequency and context of cell division must be controlled, and cells must differentiate properly to perform their mature functions. In addition, stem cell niches need to be maintained as a reservoir for new cells. All of these processes require intercellular signaling, whether it is a cell relaying its position to other cells, or more mature cells signaling to the stem cell niche to regulate the rate of growth. Receptor-like kinases have emerged as a major component in these diverse roles, especially within the Arabidopsis root. In this review, the functions of receptor-like kinase signaling in regulating Arabidopsis root development will be examined in theareas of root apical meristem maintenance, regulation of epidermal cell fate, lateral root development and vascular differentiation.展开更多
In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA w...In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA within the phloem sap of several plant species. It is now of considerable interest to elucidate the biological functions of these potential long-distance signal agents, to further our understanding of how plants coordinate their developmental programs at the whole-plant level. In this study, we developed a strategy for the functional analysis of phloem-mobile mRNA by focusing on IAA transcripts, whose mobility has previously been reported in melon （Cucumis melo cv. Hale＇s Best Jumbo）. Indoleacetic acid （IAA） proteins are key transcriptional regulators of auxin signaling, and are involved in a broad range of developmental processes including root development. We used a combination of vasculature-enriched sampling and hetero-grafting techniques to identify IAA18 and IAA28 as phloemmobile transcripts in the model plant Arabidopsis thaliana. Micro-grafting experiments were used to confirm that these IAA transcripts, which are generated in vascular tissues of mature leaves, are then transported into the root system where they negatively regulate lateral root formation. Based on these findings, we present a model in which auxin distribution, in combination with phloem-mobile Aux/IAA transcripts, can determine the sites of auxin action.展开更多
基金This research was supported by the National Natural Science Foundation of China(Projects 31670275,31470371,31500227,and 31900246)the Shandong Province Natural Science Foundation Major Basic Research Program(2017C03)+1 种基金the China Postdoctoral Science Foundation(2019M662332,2019T120582)the Special Support for Post-doc Creative Funding in Shandong(201901010).
文摘Auxin plays a critical role in lateral root(LR)formation.The signaling module composed of auxin-response factors(ARFs)and lateral organ boundaries domain transcription factors mediates auxin signaling to control almost every stage of LR development.Here,we show that auxin-induced degradation of the APETALA2/Ethylene Responsive Factor(AP2/ERF)transcription factor ERF13,dependent on MITOGENACTIVATED PROTEIN KINASE MPK14-mediated phosphorylation,plays an essential role in LR development.Overexpression of ERF13 results in restricted passage of the LR primordia through the endodermal layer,greatly reducing LR emergence,whereas the erf13 mutants showed an increase in emerged LR.ERF13 inhibits the expression of 3-ketoacyl-CoA synthase16(KCS16),which encodes a fatty acid elongase involved in very-long-chain fatty acid(VLCFA)biosynthesis.Overexpression of KCS16 or exogenous VLCFA treatment rescues the LR emergence defects in ERF13 overexpression lines,indicating a role downstream of the auxin-MPK14-ERF13 signaling module.Collectively,our study uncovers a novel molecular mechanism by which MPK14-mediated auxin signaling modulates LR development via ERF13-regulated VLCFA biosynthesis.
基金Supported by Natural Science Foundation of Guangdong Province" Study on Molecular Mechanism of Auxin Signal Transduction "(06025819)~~
文摘[Objective]The aim was to research the function of AtGEF1 in Rac/Rop GTPses mediate auxin signal passway.[Method]Using the transgenic plants of AtGEF1 promotor fused with GUS reporter gene and the over-expression plants of Rac/Rop GEF1 under the control of 35S promoter as materials,which were constructed from our lab,the expression pattern of GEF1 was analyzed by GUS assay using histochemical staining,and the development of seedling roots of over-expression plant of GEF1 was observed.[Result]GEF1 expression was mainly detected in root meristem,root vascular tissue,lateral roots and root hair.Furthermore,the expression level of GEF1 was highly increased with the induction of NAA.Over-expression of GEF1 was observed to enhance lateral root formation.[Conclusion]GEF1 may be involved in the regulation of development of root and root hair,and it may have redundant function in the control of lateral root development.
文摘Brassinosteroids （BRs） are natural plant hormones critical for growth and development. BR-deficient or signaling mutants show significantly shortened root phenotypes. But for a long time, it was thought that these phenotypes were solely caused by reduced root cell elongation in the mutants. Functions of BRs in regulating root development have been largely neglected. Recent detailed analyses, however, revealed that BRs are not only involved in root cell elongation but are also involved in many aspects of root development, such as maintenance of meristem size, root hair formation, lateral root initiation, gravitropic response, mycorrhiza formation, and nodulation in legume species. In this review, current findings on the functions of BRs in mediating root growth, development, and symbiosis are discussed.
文摘During plant development, the frequency and context of cell division must be controlled, and cells must differentiate properly to perform their mature functions. In addition, stem cell niches need to be maintained as a reservoir for new cells. All of these processes require intercellular signaling, whether it is a cell relaying its position to other cells, or more mature cells signaling to the stem cell niche to regulate the rate of growth. Receptor-like kinases have emerged as a major component in these diverse roles, especially within the Arabidopsis root. In this review, the functions of receptor-like kinase signaling in regulating Arabidopsis root development will be examined in theareas of root apical meristem maintenance, regulation of epidermal cell fate, lateral root development and vascular differentiation.
基金supported by a grant from the United States-Israel Binational Science Foundation(BSF 2007052,to W.J.L.and S.W.)by a Postdoctoral Fellowship for Research Abroad from the Japanese Society for the Promotion of Science(awarded to Michitaka Notaguchi).
文摘In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA within the phloem sap of several plant species. It is now of considerable interest to elucidate the biological functions of these potential long-distance signal agents, to further our understanding of how plants coordinate their developmental programs at the whole-plant level. In this study, we developed a strategy for the functional analysis of phloem-mobile mRNA by focusing on IAA transcripts, whose mobility has previously been reported in melon （Cucumis melo cv. Hale＇s Best Jumbo）. Indoleacetic acid （IAA） proteins are key transcriptional regulators of auxin signaling, and are involved in a broad range of developmental processes including root development. We used a combination of vasculature-enriched sampling and hetero-grafting techniques to identify IAA18 and IAA28 as phloemmobile transcripts in the model plant Arabidopsis thaliana. Micro-grafting experiments were used to confirm that these IAA transcripts, which are generated in vascular tissues of mature leaves, are then transported into the root system where they negatively regulate lateral root formation. Based on these findings, we present a model in which auxin distribution, in combination with phloem-mobile Aux/IAA transcripts, can determine the sites of auxin action.
