The perennial root of Astragalus membranaceus is used as a medicine,while root rot is a main factor causing reduction of quality and commodity value of A. membranaceus. The screening and research of the pathogenic spe...The perennial root of Astragalus membranaceus is used as a medicine,while root rot is a main factor causing reduction of quality and commodity value of A. membranaceus. The screening and research of the pathogenic species and their characteristics could provide theoretical and practical basis for the control of this disease. A pathogenic strain was isolated and purified from the root part of four-year-old A. membranaceus,and identified by morphological and molecular biological methods as Fusarium oxysporum. This study will provide a theoretical basis for the research of the biological characteristics and control of F. oxysporum.展开更多
Hormonal crosstalk is central for tailoring plant responses to the nature of challenges encountered.The role of antagonism between the two major defense hormones,salicylic acid(SA) and jasmonic acid(JA),and modulation...Hormonal crosstalk is central for tailoring plant responses to the nature of challenges encountered.The role of antagonism between the two major defense hormones,salicylic acid(SA) and jasmonic acid(JA),and modulation of this interplay by ethylene(ET) in favor of JA signaling pathway in plant stress responses is well recognized,but the underlying mechanism is not fully understood.Here,we show the opposing function of two transcription factors,ethylene insensitive3(EIN3) and EIN3-Like1(EIL1),in SA-mediated suppression and JAmediated activation of PLANT DEFENSIN1.2(PDF1.2).This functional duality is mediated via their effect on protein,not transcript levels of the PDF1.2 transcriptional activator octadecanoid-responsive Arabidopsis59(ORA59).Specifically,JA induces ORA59 protein levels independently of EIN3/EIL1,whereas SA reduces the protein levelsdependently of EIN3/EIL1.Co-infiltration assays revealed nuclear co-localization of ORA59 and EIN3,and splitluciferase together with yeast-two-hybrid assays established their physical interaction.The functional ramification of the physical interaction is EIN3-dependent degradation of ORA59 by the 26 S proteasome.These findings allude to SA-responsive reduction of ORA59 levels mediated by EIN3 binding to and targeting of ORA59 for degrada4tion,thus nominating ORA59 pool as a coordination node for the antagonistic function of ET/JA and SA.展开更多
基金Supported by National Natural Science Foundation of China(No.21462044,No.30860036)
文摘The perennial root of Astragalus membranaceus is used as a medicine,while root rot is a main factor causing reduction of quality and commodity value of A. membranaceus. The screening and research of the pathogenic species and their characteristics could provide theoretical and practical basis for the control of this disease. A pathogenic strain was isolated and purified from the root part of four-year-old A. membranaceus,and identified by morphological and molecular biological methods as Fusarium oxysporum. This study will provide a theoretical basis for the research of the biological characteristics and control of F. oxysporum.
基金supported by National Institutes of Health(R01GM107311)National Science Foundation(IOS-1036491and IOS1352478) grants awarded to K.D.
文摘Hormonal crosstalk is central for tailoring plant responses to the nature of challenges encountered.The role of antagonism between the two major defense hormones,salicylic acid(SA) and jasmonic acid(JA),and modulation of this interplay by ethylene(ET) in favor of JA signaling pathway in plant stress responses is well recognized,but the underlying mechanism is not fully understood.Here,we show the opposing function of two transcription factors,ethylene insensitive3(EIN3) and EIN3-Like1(EIL1),in SA-mediated suppression and JAmediated activation of PLANT DEFENSIN1.2(PDF1.2).This functional duality is mediated via their effect on protein,not transcript levels of the PDF1.2 transcriptional activator octadecanoid-responsive Arabidopsis59(ORA59).Specifically,JA induces ORA59 protein levels independently of EIN3/EIL1,whereas SA reduces the protein levelsdependently of EIN3/EIL1.Co-infiltration assays revealed nuclear co-localization of ORA59 and EIN3,and splitluciferase together with yeast-two-hybrid assays established their physical interaction.The functional ramification of the physical interaction is EIN3-dependent degradation of ORA59 by the 26 S proteasome.These findings allude to SA-responsive reduction of ORA59 levels mediated by EIN3 binding to and targeting of ORA59 for degrada4tion,thus nominating ORA59 pool as a coordination node for the antagonistic function of ET/JA and SA.
