Prolonged exposure to low temperatures during agricultural production often leads to fruit malformation in crops,significantly reducing market value.However,the underlying molecular mechanisms remain poorly understood...Prolonged exposure to low temperatures during agricultural production often leads to fruit malformation in crops,significantly reducing market value.However,the underlying molecular mechanisms remain poorly understood.In this study,we identify sugar transport protein 2(STP2)as a critical regulator of tomato fruit locule development under cold conditions.Low temperatures impair long-distance sucrose transport from leaves to shoot apices,resulting in reduced accumulation of glucose and arabinose.In response,STP2 expression is strongly upregulated in shoot apices,promoting glucose and arabinose transport.We found that the CLAVAT3-WUSCHEL(CLV3-WUS)regulatory module,which governs locule formation,relies on STP2-mediated sugar transport for CLV3 arabinosylation.Overexpression of STP2 promotes glucose and arabinose accumulation in shoot apices,enhances CLV3 arabinosylation and the WUS suppression,mitigating the multi-locular malformations induced by low temperatures.Conversely,disruption of STP2 function exacerbates locule number increases under low temperatures,which could not be rescued by exogenous sugar supplementation.Our findings reveal a key mechanism by which STP2-mediated sugar transport supports CLV3 arabinosylation to maintain fruit locule development under low temperatures,offering potential strategies to alleviate fruit malformations in winter crop cultivation.展开更多
As a peptide hormone, CLV3 restricts the stem cell number in shoot apical meristem （SAM） by interacting with CLV1/CLV2/CRN/RPK2 receptor complexes. To elucidate how the function of the CLV3 peptide in SAM maintenanc...As a peptide hormone, CLV3 restricts the stem cell number in shoot apical meristem （SAM） by interacting with CLV1/CLV2/CRN/RPK2 receptor complexes. To elucidate how the function of the CLV3 peptide in SAM maintenance is established at the amino acid （AA） level, alanine substitutions were performed by introducing point mutations to individual residues in the peptide-coding region of CLV3 and its flanking sequences. Constructs carrying such substitutions, expressed under the control of CLV3 regulatory elements, were transformed to the clv3-2 null mutant to evaluate their efficiencies in complementing its defects in SAMs in vivo. These studies showed that aspartate-8, histidine-11, glycine-6, proline-4, arginine-1, and proline-9, arranged in an order of importance, were critical, while threonine-2, valine-3, serine-5, and the previously assigned hydroxylation and arabinosylation residue proline-7 were trivial for the endogenous CLV3 function in SAM maintenance. In contrast, substitutions of flanking residues did not impose much damage on CLV3. Complementation of different alanine-substituted constructs was confirmed by measurements of the sizes of SAMs and the WUS expression levels in transgenic plants. These studies established a complete contribution map of individual residues in the peptide-coding region of CLV3 for its function in SAM, which may help to understand peptide hormones in general.展开更多
多肽配基CLAVATA3(CLV3)和转录因子WUSCHEL(WUS)构成的反馈调控环路调节拟南芥茎顶端分生区干细胞增殖与分化间的平衡.以前大家基于遗传实验的证据推测,CLV1/CLV2通过胞外域二硫键的连接形成二聚体来应答CLV3信号.2010年Clark研究组发现...多肽配基CLAVATA3(CLV3)和转录因子WUSCHEL(WUS)构成的反馈调控环路调节拟南芥茎顶端分生区干细胞增殖与分化间的平衡.以前大家基于遗传实验的证据推测,CLV1/CLV2通过胞外域二硫键的连接形成二聚体来应答CLV3信号.2010年Clark研究组发现CLV1能够与其同源蛋白BAM形成异源二聚体CLV1/BAM来参与CLV3信号传递.遗传学分析表明CLV1和CLV2/CORYNE(CRN)分属2条平行独立的信号转导通路来应答CLV3多肽信号.2010年中科院植物研究所林金星研究组通过萤火虫荧光素酶互补技术检测到CRN与CLV2相互作用,CRN和CLV1能够产生较弱的相互作用,CRN自身相互作用形成二聚体,并且CLV1,CLV2和CRN可以结合在一起形成1个复合体.Simon实验组利用荧光能量共振转移技术亦得到相同的实验结果.2010年Sawa研究组利用遗传和生化技术,发现Receptor-like Protein Kinase2(RPK2)以形成同源二聚体RPK2/RPK2的形式参与CLV3信号传递.随着蛋白质之间关系的深入研究,人们发现CLV3受体形式非常复杂,远远不是推测的CLV1/CLV1(BAM),CLV2/CRN和RPK2/RPK2 3种形式的受体模型所能全部涵盖的.展开更多
The CLAVATA3/EMBRYO SURROUNDING REGION-related(CLE)peptides are critical for stem cell homeostasis in plant shoot and root apical meristem.Although CLE genes have been reported in numerous plants,there is limited info...The CLAVATA3/EMBRYO SURROUNDING REGION-related(CLE)peptides are critical for stem cell homeostasis in plant shoot and root apical meristem.Although CLE genes have been reported in numerous plants,there is limited information for apple.Here,twenty-five MdCLE genes were identified fromapple genome(Apple Genome V1.0 predicted peptides).Analysis of chromosomal location showed that the 25 MdCLE genes were located on 12 of 17 apple chromosomes.Genetic structure analysis showed that 21 of 25 the MdCLE genes were intron-free.Expression patterns showed thatmost of the MdCLE genes showed higher expression levels in leaves and root compared with the other tissues.In addition,expression analysis demonstrated that MdCLE genes had different gene expression patterns for abiotic stress treatment,suggesting their potential roles in acclimation of apple to adverse environments.The 25 MdCLE genes encoded 19 different CLE peptides,and they were divided into two groups depending on their effects on the inhibition of Arabidopsis root growth.Our results suggest that MdCLE genesmay have an important but redundant function in regulating plant growth and development,and this work provides valuable references for further investigation of the biological functions of MdCLE genes.展开更多
In plants, the meristem has to maintain a separate population of pluripotent cells that serve two main tasks, i.e., self-maintenance and organ initiation, which are separated spatially in meristem. Prior to our study,...In plants, the meristem has to maintain a separate population of pluripotent cells that serve two main tasks, i.e., self-maintenance and organ initiation, which are separated spatially in meristem. Prior to our study, WUS and WUS.like WOX genes had been reported as essential for the development of the SAM. In this study, the consequences of gain of WOX1 function are described. Here we report the identification of an Arabidopsis gain-of-function mutant woxl-D, in which the expression level of the WOX1 （WUSCHEL HOMEOBOX 1） was elevated and subtle defects in meristem development were observed. The woxl-D mutant phenotype is dwarfed and slightly bushy, with a smaller shoot apex. The woxl-D mutant also produced small and dark green leaves, and exhibited a failure in anther dehiscence and male sterility. Molecular evidences showed that the transcription of the stem cell marker gene CLV3 was down-regulated in the meristem of woxl-D but accumulated in the other regions, i.e., in the root-hypocotyl junction and at the sites for lateral root initiation. The fact that the organ size and cell size in leaves of woxl-D are smaller than those in wild type suggests that cell expansion is possibly affected in order to have partially retarded the development of lateral organs, possibly through alteration of CLV3 expression pattern in the meristem. An S-adenosylmethionine decarboxylase （SAMDC） protein, SAMDC1, was found able to interact with WOX1 by yeast two-hybrid and pull-down assays in vitro. HPLC analysis revealed a significant reduction of polyamine content in woxl-D. Our results suggest that WOX1 plays an important role in meristem development in Arabidopsis, possibly via regulation of SAMDC activity and polyamine homeostasis, and/or by regulating CLV3 expression.展开更多
Ligand-receptor signaling initiated by the CLAVATA3/ENDOSPERM SURROUNDING REGION （CLE） family peptides is critical in regulating cell division and differentiation in meristematic tissues in plants. Biologically acti...Ligand-receptor signaling initiated by the CLAVATA3/ENDOSPERM SURROUNDING REGION （CLE） family peptides is critical in regulating cell division and differentiation in meristematic tissues in plants. Biologically active CLE peptides are released from precursor proteins via proteolytic processing. The mature form of CLE ligands consists of 12-13 amino acids with several post-translational modifications. This review summarizes recent progress toward understanding the proteolytic activities that cleave precursor proteins to release CLE peptides, the molecular structure and function of mature CLE ligands, and interactions between CLE ligands and cor- responding leucine-rich repeat （LRR） receptor-like kinases （RLKs）.展开更多
Phosphatidylserine （PS）, a quantitatively minor membrane phospholipid, is involved in many biological processes besides its role in membrane structure. One PS synthesis gene, PHOSPHATIDYLSERINE SYNTHASE1 （PSSl）, h...Phosphatidylserine （PS）, a quantitatively minor membrane phospholipid, is involved in many biological processes besides its role in membrane structure. One PS synthesis gene, PHOSPHATIDYLSERINE SYNTHASE1 （PSSl）, has been discovered to be required for microspore development in Arabidopsis thaliana L. but how PSS1 affects postembryonic development is still largely unknown. Here, we show that PSSl is also required for inflorescence meristem and organ development in Arabidopsis. Disruption of PSSI causes severe dwarfism, smaller lateral organs and reduced size of inflorescence meristem. Morphological and molecular studies suggest that both cell division and cell elongation are affected in the pssl-1 mutant. RNA in situ hybridization and promoter GUS analysis show that expression of both WUSCHEL （WUS） and CLA VA TA3 （CL V3） depend on PSS1. Moreover, the defect in meristem maintenance is recovered and the expression of WUS and CLV3 are restored in the pssl-1 clvl-1 double mutant. Both SHOOTSTEMLESS （STM） and BREVIPEDICELLUS （BP） are upregulated, and auxin distribution is disrupted in rosette leaves of pssl-1. However, expression of BP, which is also a regulator of internode development, is lost in the pssl-1 inflorescence stem. Our data suggest that PSS1 plays essential roles in inflorescence meristem maintenance through the WUS-CLV pathway, and in leaf and internode development by differentially regulating the class I KNOX genes.展开更多
基金supported by the Key Research and Development Program of China(2023YFD2000600)the National Natural Science Foundation of China(32430092)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(SN-ZJU-SIAS-0011).
文摘Prolonged exposure to low temperatures during agricultural production often leads to fruit malformation in crops,significantly reducing market value.However,the underlying molecular mechanisms remain poorly understood.In this study,we identify sugar transport protein 2(STP2)as a critical regulator of tomato fruit locule development under cold conditions.Low temperatures impair long-distance sucrose transport from leaves to shoot apices,resulting in reduced accumulation of glucose and arabinose.In response,STP2 expression is strongly upregulated in shoot apices,promoting glucose and arabinose transport.We found that the CLAVAT3-WUSCHEL(CLV3-WUS)regulatory module,which governs locule formation,relies on STP2-mediated sugar transport for CLV3 arabinosylation.Overexpression of STP2 promotes glucose and arabinose accumulation in shoot apices,enhances CLV3 arabinosylation and the WUS suppression,mitigating the multi-locular malformations induced by low temperatures.Conversely,disruption of STP2 function exacerbates locule number increases under low temperatures,which could not be rescued by exogenous sugar supplementation.Our findings reveal a key mechanism by which STP2-mediated sugar transport supports CLV3 arabinosylation to maintain fruit locule development under low temperatures,offering potential strategies to alleviate fruit malformations in winter crop cultivation.
基金This work was supported by the Ministry of China （2007CB948200）, Chinese of Science and Technology Academy of Sciences （1105000003 and 200904910192008）, and the National Natural Science Foundation of China （30821007 and 31000623）. ACKNOWLEDGMENTS We thank Dr Trevor L. Wang at the John Innes Centre, UK, for critical reading of the manuscript Prof. Kexue Xu at the Institute of Botany, Chinese Academy of Sciences, for suggestions regarding the statistica~ data analysis and Dr Wei Gao at Beijing Forestry University for discussions of the results. No conflict of interest declared.
文摘As a peptide hormone, CLV3 restricts the stem cell number in shoot apical meristem （SAM） by interacting with CLV1/CLV2/CRN/RPK2 receptor complexes. To elucidate how the function of the CLV3 peptide in SAM maintenance is established at the amino acid （AA） level, alanine substitutions were performed by introducing point mutations to individual residues in the peptide-coding region of CLV3 and its flanking sequences. Constructs carrying such substitutions, expressed under the control of CLV3 regulatory elements, were transformed to the clv3-2 null mutant to evaluate their efficiencies in complementing its defects in SAMs in vivo. These studies showed that aspartate-8, histidine-11, glycine-6, proline-4, arginine-1, and proline-9, arranged in an order of importance, were critical, while threonine-2, valine-3, serine-5, and the previously assigned hydroxylation and arabinosylation residue proline-7 were trivial for the endogenous CLV3 function in SAM maintenance. In contrast, substitutions of flanking residues did not impose much damage on CLV3. Complementation of different alanine-substituted constructs was confirmed by measurements of the sizes of SAMs and the WUS expression levels in transgenic plants. These studies established a complete contribution map of individual residues in the peptide-coding region of CLV3 for its function in SAM, which may help to understand peptide hormones in general.
文摘多肽配基CLAVATA3(CLV3)和转录因子WUSCHEL(WUS)构成的反馈调控环路调节拟南芥茎顶端分生区干细胞增殖与分化间的平衡.以前大家基于遗传实验的证据推测,CLV1/CLV2通过胞外域二硫键的连接形成二聚体来应答CLV3信号.2010年Clark研究组发现CLV1能够与其同源蛋白BAM形成异源二聚体CLV1/BAM来参与CLV3信号传递.遗传学分析表明CLV1和CLV2/CORYNE(CRN)分属2条平行独立的信号转导通路来应答CLV3多肽信号.2010年中科院植物研究所林金星研究组通过萤火虫荧光素酶互补技术检测到CRN与CLV2相互作用,CRN和CLV1能够产生较弱的相互作用,CRN自身相互作用形成二聚体,并且CLV1,CLV2和CRN可以结合在一起形成1个复合体.Simon实验组利用荧光能量共振转移技术亦得到相同的实验结果.2010年Sawa研究组利用遗传和生化技术,发现Receptor-like Protein Kinase2(RPK2)以形成同源二聚体RPK2/RPK2的形式参与CLV3信号传递.随着蛋白质之间关系的深入研究,人们发现CLV3受体形式非常复杂,远远不是推测的CLV1/CLV1(BAM),CLV2/CRN和RPK2/RPK2 3种形式的受体模型所能全部涵盖的.
基金This research was funded by National Key R&D Program of China(Grant No.2018YFD1000100)National Natural Science Foundation of China(Grant No.31772288)+1 种基金Ministry of Agriculture of China(Grant No.CARS-27)Science and Technology Program of Yunnan Province(Grant No.2019ZG002-1-03).
文摘The CLAVATA3/EMBRYO SURROUNDING REGION-related(CLE)peptides are critical for stem cell homeostasis in plant shoot and root apical meristem.Although CLE genes have been reported in numerous plants,there is limited information for apple.Here,twenty-five MdCLE genes were identified fromapple genome(Apple Genome V1.0 predicted peptides).Analysis of chromosomal location showed that the 25 MdCLE genes were located on 12 of 17 apple chromosomes.Genetic structure analysis showed that 21 of 25 the MdCLE genes were intron-free.Expression patterns showed thatmost of the MdCLE genes showed higher expression levels in leaves and root compared with the other tissues.In addition,expression analysis demonstrated that MdCLE genes had different gene expression patterns for abiotic stress treatment,suggesting their potential roles in acclimation of apple to adverse environments.The 25 MdCLE genes encoded 19 different CLE peptides,and they were divided into two groups depending on their effects on the inhibition of Arabidopsis root growth.Our results suggest that MdCLE genesmay have an important but redundant function in regulating plant growth and development,and this work provides valuable references for further investigation of the biological functions of MdCLE genes.
基金supported by the National Natural Science Foundation of China(90717003 and 30625002 to L.-J. Q.)partially by the 111 Project
文摘In plants, the meristem has to maintain a separate population of pluripotent cells that serve two main tasks, i.e., self-maintenance and organ initiation, which are separated spatially in meristem. Prior to our study, WUS and WUS.like WOX genes had been reported as essential for the development of the SAM. In this study, the consequences of gain of WOX1 function are described. Here we report the identification of an Arabidopsis gain-of-function mutant woxl-D, in which the expression level of the WOX1 （WUSCHEL HOMEOBOX 1） was elevated and subtle defects in meristem development were observed. The woxl-D mutant phenotype is dwarfed and slightly bushy, with a smaller shoot apex. The woxl-D mutant also produced small and dark green leaves, and exhibited a failure in anther dehiscence and male sterility. Molecular evidences showed that the transcription of the stem cell marker gene CLV3 was down-regulated in the meristem of woxl-D but accumulated in the other regions, i.e., in the root-hypocotyl junction and at the sites for lateral root initiation. The fact that the organ size and cell size in leaves of woxl-D are smaller than those in wild type suggests that cell expansion is possibly affected in order to have partially retarded the development of lateral organs, possibly through alteration of CLV3 expression pattern in the meristem. An S-adenosylmethionine decarboxylase （SAMDC） protein, SAMDC1, was found able to interact with WOX1 by yeast two-hybrid and pull-down assays in vitro. HPLC analysis revealed a significant reduction of polyamine content in woxl-D. Our results suggest that WOX1 plays an important role in meristem development in Arabidopsis, possibly via regulation of SAMDC activity and polyamine homeostasis, and/or by regulating CLV3 expression.
基金supported by a startup fund from the Tobacco Research Institute,Chinese Academy of Agricultural Sciences
文摘Ligand-receptor signaling initiated by the CLAVATA3/ENDOSPERM SURROUNDING REGION （CLE） family peptides is critical in regulating cell division and differentiation in meristematic tissues in plants. Biologically active CLE peptides are released from precursor proteins via proteolytic processing. The mature form of CLE ligands consists of 12-13 amino acids with several post-translational modifications. This review summarizes recent progress toward understanding the proteolytic activities that cleave precursor proteins to release CLE peptides, the molecular structure and function of mature CLE ligands, and interactions between CLE ligands and cor- responding leucine-rich repeat （LRR） receptor-like kinases （RLKs）.
基金supported by the National Natural Science Foundation of China(Grant numbers 90717106 and 30821004 to D.L.
文摘Phosphatidylserine （PS）, a quantitatively minor membrane phospholipid, is involved in many biological processes besides its role in membrane structure. One PS synthesis gene, PHOSPHATIDYLSERINE SYNTHASE1 （PSSl）, has been discovered to be required for microspore development in Arabidopsis thaliana L. but how PSS1 affects postembryonic development is still largely unknown. Here, we show that PSSl is also required for inflorescence meristem and organ development in Arabidopsis. Disruption of PSSI causes severe dwarfism, smaller lateral organs and reduced size of inflorescence meristem. Morphological and molecular studies suggest that both cell division and cell elongation are affected in the pssl-1 mutant. RNA in situ hybridization and promoter GUS analysis show that expression of both WUSCHEL （WUS） and CLA VA TA3 （CL V3） depend on PSS1. Moreover, the defect in meristem maintenance is recovered and the expression of WUS and CLV3 are restored in the pssl-1 clvl-1 double mutant. Both SHOOTSTEMLESS （STM） and BREVIPEDICELLUS （BP） are upregulated, and auxin distribution is disrupted in rosette leaves of pssl-1. However, expression of BP, which is also a regulator of internode development, is lost in the pssl-1 inflorescence stem. Our data suggest that PSS1 plays essential roles in inflorescence meristem maintenance through the WUS-CLV pathway, and in leaf and internode development by differentially regulating the class I KNOX genes.
