植物运输抑制响应蛋白1(transport inhibitor protein 1,TIR1)是一种生长素受体,在生长素信号转导过程中发挥重要作用。目前有关马铃薯生长素受体基因的研究尚未见报道。本研究是从前期工作中获得EST序列,利用NCBI中的BLAST工具,对原始...植物运输抑制响应蛋白1(transport inhibitor protein 1,TIR1)是一种生长素受体,在生长素信号转导过程中发挥重要作用。目前有关马铃薯生长素受体基因的研究尚未见报道。本研究是从前期工作中获得EST序列,利用NCBI中的BLAST工具,对原始序列进行同源性分析,选择与原始序列相似度最高的一条同源序列。通过电子克隆技术,得到TIR1基因。采用生物信息学方法对基因序列、编码氨基酸、理化性质、跨膜结构域、亲/疏水性、信号肽、磷酸化位点、N-端糖基化位点、高级结构等进行分析。结果表明,TIR1基因cDNA全长1740 bp,编码580个氨基酸,分子量64.68 kD,理论等电点5.60,亲水性系数0.034,不稳定系数56.67,为不稳定酸性疏水性蛋白,编码蛋白含有59个磷酸化位点,4个N-端糖基化位点,无信号肽、跨膜区域,高级结构主要由α螺旋和无规卷曲序列组成。通过系统进化分析,TIR1蛋白与烟草、番茄和拟南芥等植物中的TIR1蛋白同源性较高。亚细胞定位分析,TIR1基因主要位于细胞核,小部分可能位于线粒体。研究结果为马铃薯TIR1基因的试验克隆及功能验证研究提供了理论依据。展开更多
The phytohormone auxin plays a pivotal role in governing plant growth and development.Although the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX(TIR1/AFB)receptors function in both the nucleus and cytoplasm,the ...The phytohormone auxin plays a pivotal role in governing plant growth and development.Although the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX(TIR1/AFB)receptors function in both the nucleus and cytoplasm,the mechanism governing the distribution of TIR1/AFBs between these cellular compartments remains unknown.In this study,we demonstrate that auxin-mediated oxidation of TIR1/AFB2 is essential for their targeting to the nucleus.We showed that small active molecules,reactive oxygen species(ROS)and nitric oxide(NO),are indispensable for the nucleo-cytoplasmic distribution of TIR1/AFB2 in trichoblasts and root hairs.Further studies revealed that this process is regulated by the FERONIA receptor kinase–NADPH oxidase signaling pathway.Interestingly,ROS and NO initiate oxidative modifications in TIR1C140/516 and AFB2C135/511,facilitating their subsequent nuclear import.The oxidized forms of TIR1C140/516 and AFB2C135/511 play a crucial role in enhancing the function of TIR1 and AFB2 in transcriptional auxin responses.Collectively,our study reveals a novel mechanism by which auxin stimulates the transport of TIR1/AFB2 from the cytoplasm to the nucleus,orchestrated by the FERONIA–ROS signaling pathway.展开更多
The phytohormone auxin exerts control over remarkable developmental processes in plants.It moves from cell to cell,resulting in the creation of both extracellular auxin and intracellular auxin,which are recognized by ...The phytohormone auxin exerts control over remarkable developmental processes in plants.It moves from cell to cell,resulting in the creation of both extracellular auxin and intracellular auxin,which are recognized by distinct auxin receptors.These two auxin signaling systems govern different auxin responses while working together to regulate plant development.In this review,we outline the latest research advancements in unraveling these auxin signaling pathways,encompassing auxin perception and signaling transductions.We emphasize the interaction between extracellular and intracellular auxin,which contributes to the intricate role of auxin in plant development.展开更多
In Arabidopsis thaliana,canonical auxin-dependent gene regulation is mediated by 23 transcription factors from the AUXIN RESPONSE FACTOR(ARF)family that interact with auxin/indole acetic acid repressors(Aux/IAAs),whic...In Arabidopsis thaliana,canonical auxin-dependent gene regulation is mediated by 23 transcription factors from the AUXIN RESPONSE FACTOR(ARF)family that interact with auxin/indole acetic acid repressors(Aux/IAAs),which themselves form co-receptor complexes with one of six TRANSPORT INHIBITOR*!/AUXIN-SIGNALLING F-BOX(TIR1/AFB)proteins.Different combinations of co-receptors drive specific sensing outputs,allowing auxin to control a myriad of processes.ARF6 and ARF8 are positive regulators of adventitious root initiation upstream of jasmonate,but the exact auxin co-receptor complexes controlling the transcriptional activity of these proteins has remained unknown.Here,using loss-of-function mutants we show that three Aux/IAA genes,IAA6,IAA9,and IAA17,act additively in the control of adventitious root(AR)initiation.These three IAA proteins interact with ARF6 and/or ARF8 and likely repress their activity in AR development.We show that TIR1 and AFB2 are positive regulators of AR formation and TIR1 plays a dual role in the control of jasmonic acid(JA)biosynthesis and conjugation,as several JA biosynthesis genes are up-regulated in the tir1-1 mutant.These results lead us to propose that in the presence of auxin,TIR1 and AFB2 form specific sensing complexes with IAA6,IAA9,and/or IAA17 to modulate JA homeostasis and control AR initiation.展开更多
Dear Editor,Auxin is the major plant hormone regulating growth and development(Friml,2022).Forward genetic approaches have identified major components of auxin signaling and established the canonical mechanism mediati...Dear Editor,Auxin is the major plant hormone regulating growth and development(Friml,2022).Forward genetic approaches have identified major components of auxin signaling and established the canonical mechanism mediating transcriptional and thus developmental reprogramming in Arabidopsis thaliana.In this textbook view,TRANSPORT INHIBITOR RESPONSE 1(TIR1)/AUXIN-SIGNALING F-BOX(AFB)proteins are auxin receptors,which act as F-box subunits determining the substrate specificity of the Skp1-Cullin1-F box protein(SCF)type E3 ubiquitin ligase complex.Auxin acts as a"molecular glue,"increasing the affinity between TIR1/AFBs and the Auxin/lndole-3-Acetic Acid(Aux/IAA)repressors.Subsequently,Aux/IAAs are ubiquitinated and degraded,thus releasing auxin transcription factors from their repression and making them free to mediate transcription of auxin response genes(Yu et al.,2022).展开更多
基金supported by grants from the National Natural Science Foundation of China(32230009,31770307,31972863)the Science and Technology Innovation Plan Of Shanghai Science and Technology Commission(20ZR1416500).
文摘The phytohormone auxin plays a pivotal role in governing plant growth and development.Although the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX(TIR1/AFB)receptors function in both the nucleus and cytoplasm,the mechanism governing the distribution of TIR1/AFBs between these cellular compartments remains unknown.In this study,we demonstrate that auxin-mediated oxidation of TIR1/AFB2 is essential for their targeting to the nucleus.We showed that small active molecules,reactive oxygen species(ROS)and nitric oxide(NO),are indispensable for the nucleo-cytoplasmic distribution of TIR1/AFB2 in trichoblasts and root hairs.Further studies revealed that this process is regulated by the FERONIA receptor kinase–NADPH oxidase signaling pathway.Interestingly,ROS and NO initiate oxidative modifications in TIR1C140/516 and AFB2C135/511,facilitating their subsequent nuclear import.The oxidized forms of TIR1C140/516 and AFB2C135/511 play a crucial role in enhancing the function of TIR1 and AFB2 in transcriptional auxin responses.Collectively,our study reveals a novel mechanism by which auxin stimulates the transport of TIR1/AFB2 from the cytoplasm to the nucleus,orchestrated by the FERONIA–ROS signaling pathway.
基金supported by the National Natural Science Foundation of China(32130010).
文摘The phytohormone auxin exerts control over remarkable developmental processes in plants.It moves from cell to cell,resulting in the creation of both extracellular auxin and intracellular auxin,which are recognized by distinct auxin receptors.These two auxin signaling systems govern different auxin responses while working together to regulate plant development.In this review,we outline the latest research advancements in unraveling these auxin signaling pathways,encompassing auxin perception and signaling transductions.We emphasize the interaction between extracellular and intracellular auxin,which contributes to the intricate role of auxin in plant development.
文摘In Arabidopsis thaliana,canonical auxin-dependent gene regulation is mediated by 23 transcription factors from the AUXIN RESPONSE FACTOR(ARF)family that interact with auxin/indole acetic acid repressors(Aux/IAAs),which themselves form co-receptor complexes with one of six TRANSPORT INHIBITOR*!/AUXIN-SIGNALLING F-BOX(TIR1/AFB)proteins.Different combinations of co-receptors drive specific sensing outputs,allowing auxin to control a myriad of processes.ARF6 and ARF8 are positive regulators of adventitious root initiation upstream of jasmonate,but the exact auxin co-receptor complexes controlling the transcriptional activity of these proteins has remained unknown.Here,using loss-of-function mutants we show that three Aux/IAA genes,IAA6,IAA9,and IAA17,act additively in the control of adventitious root(AR)initiation.These three IAA proteins interact with ARF6 and/or ARF8 and likely repress their activity in AR development.We show that TIR1 and AFB2 are positive regulators of AR formation and TIR1 plays a dual role in the control of jasmonic acid(JA)biosynthesis and conjugation,as several JA biosynthesis genes are up-regulated in the tir1-1 mutant.These results lead us to propose that in the presence of auxin,TIR1 and AFB2 form specific sensing complexes with IAA6,IAA9,and/or IAA17 to modulate JA homeostasis and control AR initiation.
基金the European Research Council Advanced Grant(ETAP-742985).
文摘Dear Editor,Auxin is the major plant hormone regulating growth and development(Friml,2022).Forward genetic approaches have identified major components of auxin signaling and established the canonical mechanism mediating transcriptional and thus developmental reprogramming in Arabidopsis thaliana.In this textbook view,TRANSPORT INHIBITOR RESPONSE 1(TIR1)/AUXIN-SIGNALING F-BOX(AFB)proteins are auxin receptors,which act as F-box subunits determining the substrate specificity of the Skp1-Cullin1-F box protein(SCF)type E3 ubiquitin ligase complex.Auxin acts as a"molecular glue,"increasing the affinity between TIR1/AFBs and the Auxin/lndole-3-Acetic Acid(Aux/IAA)repressors.Subsequently,Aux/IAAs are ubiquitinated and degraded,thus releasing auxin transcription factors from their repression and making them free to mediate transcription of auxin response genes(Yu et al.,2022).
