RACK1蛋白是一个高度保守的支架蛋白,介导了植物细胞许多信号转导途径,对许多重要的生物学过程起关键调控作用,包括种子萌发、幼苗生长、根系发育、激素介导的信号转导、对非生物胁迫的应答、植物的免疫防御等。南方科技大学梁建生教授...RACK1蛋白是一个高度保守的支架蛋白,介导了植物细胞许多信号转导途径,对许多重要的生物学过程起关键调控作用,包括种子萌发、幼苗生长、根系发育、激素介导的信号转导、对非生物胁迫的应答、植物的免疫防御等。南方科技大学梁建生教授团队于2023年3月在《Journal of Integrative Plant Biology》上发表了题为“Scaffold protein RACK1A positively regulates leaf senescence by coordinating the EIN3-miR164-ORE1 transcriptional cascade in Arabidopsis”的研究论文。展开更多
木薯是一种重要的能源和淀粉作物,具有较强的抗逆性和耐贫瘠等能力。为研究木薯中EIN3基因如何被逆境信号调控,对木薯基因组数据库中的EIN3基因进行了序列分析,表明其具有典型的EIN3-like protein DNA结合结构域;其启动子区具有茉莉酸...木薯是一种重要的能源和淀粉作物,具有较强的抗逆性和耐贫瘠等能力。为研究木薯中EIN3基因如何被逆境信号调控,对木薯基因组数据库中的EIN3基因进行了序列分析,表明其具有典型的EIN3-like protein DNA结合结构域;其启动子区具有茉莉酸响应元件等多种响应元件。本研究以木薯品种"华南八号"悬浮培养细胞为材料,利用q RT-PCR检测木薯EIN3基因在乙烯利和茉莉酸甲酯处理后的表达特性。结果显示:EIN3在乙烯处理后,基因表达在8 h内呈现持续上升趋势;而茉莉酸甲酯处理后则整体呈现先上升后下降的趋势,且在2 h基因表达量最大。说明EIN3基因可被乙烯和茉莉酸信号调控,并推测其可受不同激素信号的整合后的综合调控,可参与到植物体内一系列多种生理生化过程。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 m...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 JA- mediated activation of PLANT DEFENSINI.2 （PDFI.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 levels dependently of EIN3/EIL1. Co-infiltration assays revealed nuclear co-localization of ORA59 and EIN3, and split- luciferase 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 26S 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
Seed size critically affects grain yield of crops and hence represents a key breeding target.The develop-ment of embryo-nourishing endosperm is a key driver of seed expansion.We here report unexpected dual roles of th...Seed size critically affects grain yield of crops and hence represents a key breeding target.The develop-ment of embryo-nourishing endosperm is a key driver of seed expansion.We here report unexpected dual roles of the transcription factor EIN3 in regulating seed size.These EIN3 functions have remained largely undiscovered because they oppose each other.Capitalizing on the analysis of multiple ethylene biosynthesis mutants,we demonstrate that EIN3 represses endosperm and seed development in a pathway regulated by ethylene.We,in addition,provide evidence that EIN3-mediated synergid nucleus disintegration promotes endosperm expansion.Interestingly,synergid nucleus disintegration is not affected in various ethylene biosynthesis mutants,suggesting that this promoting function of EIN3 is inde-pendent of ethylene.Whereas the growth-inhibitory ethylene-dependent EIN3 action appears to be encoded by sporophytic tissue,the growth-promoting role of EIN3 is induced by fertilization,revealing a generation conflict that converges toward the key signaling component EIN3.展开更多
Mitogen-activated protein kinases(MPKs)play essential roles in guard cell signaling,but whether MPK cascades participate in guard cell ethylene signaling and interact with hydrogen peroxide(H2O2),nitric oxide(NO),and ...Mitogen-activated protein kinases(MPKs)play essential roles in guard cell signaling,but whether MPK cascades participate in guard cell ethylene signaling and interact with hydrogen peroxide(H2O2),nitric oxide(NO),and ethylene-signaling components remain unclear.Here,we report that ethylene activated MPK3 and MPK6 in the leaves of wild-type Arabidopsis thaliana as well as ethylene insensitive2(ein2),ein3,nitrate reductase1(nia1),and nia2 mutants,but this effect was impaired in ethylene response1(etr1),nicotinamide adenine dinucleotide phosphate oxidase AtrbohF,mpk kinase1(mkk1),and mkk3 mutants.By contrast,the constitutive triple response1(ctr1)mutant had constitutively active MPK3 and MPK6.Yeast two-hybrid,bimolecular fluorescence complementation,and pull-down assays indicated that MPK3 and MPK6 physically interacted with MKK1,MKK3,and the C-terminal region of EIN2(EIN2 CEND).mkk1,mkk3,mpk3,and mpk6 mutants had typical levels of ethylene-induced H2O2 generation but impaired ethylene-induced EIN2 CEND cleavage and nuclear translocation,EIN3 protein accumulation,NO production in guard cells,and stomatal closure.These results show that the MKK1/3–MPK3/6 cascade mediates ethylene-induced stomatal closure by functioning downstream of ETR1,CTR1,and H2O2 to interact with EIN2,thereby promoting EIN3 accumulation and EIN3-dependent NO production in guard cells.展开更多
文摘RACK1蛋白是一个高度保守的支架蛋白,介导了植物细胞许多信号转导途径,对许多重要的生物学过程起关键调控作用,包括种子萌发、幼苗生长、根系发育、激素介导的信号转导、对非生物胁迫的应答、植物的免疫防御等。南方科技大学梁建生教授团队于2023年3月在《Journal of Integrative Plant Biology》上发表了题为“Scaffold protein RACK1A positively regulates leaf senescence by coordinating the EIN3-miR164-ORE1 transcriptional cascade in Arabidopsis”的研究论文。
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 JA- mediated activation of PLANT DEFENSINI.2 （PDFI.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 levels dependently of EIN3/EIL1. Co-infiltration assays revealed nuclear co-localization of ORA59 and EIN3, and split- luciferase 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 26S 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.
基金support from tho Europoan Rosearch Council to R.G.(ERC Consolidator Grant"bi-BL OCK"ID 646644,ERC Proof of Concept Grant"TnVolve"ID 957547).
文摘Seed size critically affects grain yield of crops and hence represents a key breeding target.The develop-ment of embryo-nourishing endosperm is a key driver of seed expansion.We here report unexpected dual roles of the transcription factor EIN3 in regulating seed size.These EIN3 functions have remained largely undiscovered because they oppose each other.Capitalizing on the analysis of multiple ethylene biosynthesis mutants,we demonstrate that EIN3 represses endosperm and seed development in a pathway regulated by ethylene.We,in addition,provide evidence that EIN3-mediated synergid nucleus disintegration promotes endosperm expansion.Interestingly,synergid nucleus disintegration is not affected in various ethylene biosynthesis mutants,suggesting that this promoting function of EIN3 is inde-pendent of ethylene.Whereas the growth-inhibitory ethylene-dependent EIN3 action appears to be encoded by sporophytic tissue,the growth-promoting role of EIN3 is induced by fertilization,revealing a generation conflict that converges toward the key signaling component EIN3.
基金supported by the National Natural Science Foundation of China(31570397,31870375)the Natural Science Research Plan of Shaanxi Province of China(2016JZ008)the Excellent Doctoral Dissertation Project of Shaanxi Normal University(2017TS037).
文摘Mitogen-activated protein kinases(MPKs)play essential roles in guard cell signaling,but whether MPK cascades participate in guard cell ethylene signaling and interact with hydrogen peroxide(H2O2),nitric oxide(NO),and ethylene-signaling components remain unclear.Here,we report that ethylene activated MPK3 and MPK6 in the leaves of wild-type Arabidopsis thaliana as well as ethylene insensitive2(ein2),ein3,nitrate reductase1(nia1),and nia2 mutants,but this effect was impaired in ethylene response1(etr1),nicotinamide adenine dinucleotide phosphate oxidase AtrbohF,mpk kinase1(mkk1),and mkk3 mutants.By contrast,the constitutive triple response1(ctr1)mutant had constitutively active MPK3 and MPK6.Yeast two-hybrid,bimolecular fluorescence complementation,and pull-down assays indicated that MPK3 and MPK6 physically interacted with MKK1,MKK3,and the C-terminal region of EIN2(EIN2 CEND).mkk1,mkk3,mpk3,and mpk6 mutants had typical levels of ethylene-induced H2O2 generation but impaired ethylene-induced EIN2 CEND cleavage and nuclear translocation,EIN3 protein accumulation,NO production in guard cells,and stomatal closure.These results show that the MKK1/3–MPK3/6 cascade mediates ethylene-induced stomatal closure by functioning downstream of ETR1,CTR1,and H2O2 to interact with EIN2,thereby promoting EIN3 accumulation and EIN3-dependent NO production in guard cells.
