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Liu X, Zhu D, Zhao F, Gao Y, Li J, Li Y. VAMP726 and VAMP725 regulate vesicle secretion and pollen tube growth in Arabidopsis. PLANT CELL REPORTS 2023; 42:1951-1965. [PMID: 37805949 DOI: 10.1007/s00299-023-03075-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 09/18/2023] [Indexed: 10/10/2023]
Abstract
KEY MESSAGE VAMP726/VAMP725 and SYP131 can form a part of a SNARE complex to mediate vesicle secretion at the pollen tube apex. Secretory vesicle fusion with the plasma membrane of the pollen tube tip is a key step in pollen tube growth. Membrane fusion was mediated by SNAREs. However, little is known about the composition and function of the SNARE complex during pollen tube tip growth. In this study, we constructed a double mutant vamp725 vamp726 via CRISPR‒Cas9. Fluorescence labeling combined with microscopic observation, luciferase complementation imaging, co-immunoprecipitation and GST pull-down were applied in the study. We show that double mutation of the R-SNAREs VAMP726 and VAMP725 significantly inhibits pollen tube growth in Arabidopsis and slows vesicle exocytosis at the apex of the pollen tube. GFP-VAMP726 and VAMP725-GFP localize mainly to secretory vesicles and the plasma membrane at the apex of the pollen tube. In addition, fluorescence recovery after photobleaching (FRAP) experiments showed that mCherry-VAMP726 colocalizes with Qa-SNARE SYP131 in the central region of the pollen tube apical plasma membrane. Furthermore, we found that VAMP726 and VAMP725 can interact with the SYP131. Based on these results, we suggest that VAMP726/VAMP725 and SYP131 can form a part of a SNARE complex to mediate vesicle secretion at the pollen tube apex, and vesicle secretion may mainly occur at the central region of the pollen tube apical plasma membrane.
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Affiliation(s)
- Xinyan Liu
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Dandan Zhu
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Fuli Zhao
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yadan Gao
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Jianji Li
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yan Li
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
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Robinson R, Sprott D, Couroux P, Routly E, Labbé N, Xing T, Robert LS. The triticale mature pollen and stigma proteomes - assembling the proteins for a productive encounter. J Proteomics 2023; 278:104867. [PMID: 36870675 DOI: 10.1016/j.jprot.2023.104867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/13/2023] [Accepted: 02/20/2023] [Indexed: 03/06/2023]
Abstract
Triticeae crops are major contributors to global food production and ensuring their capacity to reproduce and generate seeds is critical. However, despite their importance our knowledge of the proteins underlying Triticeae reproduction is severely lacking and this is not only true of pollen and stigma development, but also of their pivotal interaction. When the pollen grain and stigma are brought together they have each accumulated the proteins required for their intended meeting and accordingly studying their mature proteomes is bound to reveal proteins involved in their diverse and complex interactions. Using triticale as a Triticeae representative, gel-free shotgun proteomics was used to identify 11,533 and 2977 mature stigma and pollen proteins respectively. These datasets, by far the largest to date, provide unprecedented insights into the proteins participating in Triticeae pollen and stigma development and interactions. The study of the Triticeae stigma has been particularly neglected. To begin filling this knowledge gap, a developmental iTRAQ analysis was performed revealing 647 proteins displaying differential abundance as the stigma matures in preparation for pollination. An in-depth comparison to an equivalent Brassicaceae analysis divulged both conservation and diversification in the makeup and function of proteins involved in the pollen and stigma encounter. SIGNIFICANCE: Successful pollination brings together the mature pollen and stigma thus initiating an intricate series of molecular processes vital to crop reproduction. In the Triticeae crops (e.g. wheat, barley, rye, triticale) there persists a vast deficit in our knowledge of the proteins involved which needs to be addressed if we are to face the many upcoming challenges to crop production such as those associated with climate change. At maturity, both the pollen and stigma have acquired the protein complement necessary for their forthcoming encounter and investigating their proteomes will inevitably provide unprecedented insights into the proteins enabling their interactions. By combining the analysis of the most comprehensive Triticeae pollen and stigma global proteome datasets to date with developmental iTRAQ investigations, proteins implicated in the different phases of pollen-stigma interaction enabling pollen adhesion, recognition, hydration, germination and tube growth, as well as those underlying stigma development were revealed. Extensive comparisons between equivalent Triticeae and Brassiceae datasets highlighted both the conservation of biological processes in line with the shared goal of activating the pollen grain and promoting pollen tube invasion of the pistil to effect fertilization, as well as the significant distinctions in their proteomes consistent with the considerable differences in their biochemistry, physiology and morphology.
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Affiliation(s)
- Reneé Robinson
- Ottawa Research and Development Centre, 960 Carling Ave., Ottawa, Ontario K1A 0C6, Canada; Carleton University, Department of Biology, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - David Sprott
- Ottawa Research and Development Centre, 960 Carling Ave., Ottawa, Ontario K1A 0C6, Canada
| | - Philippe Couroux
- Ottawa Research and Development Centre, 960 Carling Ave., Ottawa, Ontario K1A 0C6, Canada
| | - Elizabeth Routly
- Ottawa Research and Development Centre, 960 Carling Ave., Ottawa, Ontario K1A 0C6, Canada
| | - Natalie Labbé
- Ottawa Research and Development Centre, 960 Carling Ave., Ottawa, Ontario K1A 0C6, Canada
| | - Tim Xing
- Carleton University, Department of Biology, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Laurian S Robert
- Ottawa Research and Development Centre, 960 Carling Ave., Ottawa, Ontario K1A 0C6, Canada.
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Lu C, Peng Z, Liu Y, Li G, Wan S. Genome-Wide Analysis of the SNARE Family in Cultivated Peanut ( Arachis hypogaea L.) Reveals That Some Members Are Involved in Stress Responses. Int J Mol Sci 2023; 24:ijms24087103. [PMID: 37108265 PMCID: PMC10139436 DOI: 10.3390/ijms24087103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/31/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
The superfamily of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins mediates membrane fusion during vesicular transport between endosomes and the plasma membrane in eukaryotic cells, playing a vital role in plant development and responses to biotic and abiotic stresses. Peanut (Arachis hypogaea L.) is a major oilseed crop worldwide that produces pods below ground, which is rare in flowering plants. To date, however, there has been no systematic study of SNARE family proteins in peanut. In this study, we identified 129 putative SNARE genes from cultivated peanut (A. hypogaea) and 127 from wild peanut (63 from Arachis duranensis, 64 from Arachis ipaensis). We sorted the encoded proteins into five subgroups (Qa-, Qb-, Qc-, Qb+c- and R-SNARE) based on their phylogenetic relationships with Arabidopsis SNAREs. The genes were unevenly distributed on all 20 chromosomes, exhibiting a high rate of homolog retention from their two ancestors. We identified cis-acting elements associated with development, biotic and abiotic stresses in the promoters of peanut SNARE genes. Transcriptomic data showed that expression of SNARE genes is tissue-specific and stress inducible. We hypothesize that AhVTI13b plays an important role in the storage of lipid proteins, while AhSYP122a, AhSNAP33a and AhVAMP721a might play an important role in development and stress responses. Furthermore, we showed that three AhSNARE genes (AhSYP122a, AhSNAP33a and AhVAMP721) enhance cold and NaCl tolerance in yeast (Saccharomyces cerevisiae), especially AhSNAP33a. This systematic study provides valuable information about the functional characteristics of AhSNARE genes in the development and regulation of abiotic stress responses in peanut.
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Affiliation(s)
- Chaoxia Lu
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Zhenying Peng
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Yiyang Liu
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Guowei Li
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Shubo Wan
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Shandong Academy of Agricultural Sciences, Jinan 250100, China
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Luo C, Shi Y, Xiang Y. SNAREs Regulate Vesicle Trafficking During Root Growth and Development. FRONTIERS IN PLANT SCIENCE 2022; 13:853251. [PMID: 35360325 PMCID: PMC8964185 DOI: 10.3389/fpls.2022.853251] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 01/27/2022] [Indexed: 05/13/2023]
Abstract
SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins assemble to drive the final membrane fusion step of membrane trafficking. Thus, SNAREs are essential for membrane fusion and vesicular trafficking, which are fundamental mechanisms for maintaining cellular homeostasis. In plants, SNAREs have been demonstrated to be located in different subcellular compartments and involved in a variety of fundamental processes, such as cytokinesis, cytoskeleton organization, symbiosis, and biotic and abiotic stress responses. In addition, SNAREs can also contribute to the normal growth and development of Arabidopsis. Here, we review recent progress in understanding the biological functions and signaling network of SNAREs in vesicle trafficking and the regulation of root growth and development in Arabidopsis.
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5
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Jiang X, Fan L, Li P, Zou X, Zhang Z, Fan S, Gong J, Yuan Y, Shang H. Co-expression network and comparative transcriptome analysis for fiber initiation and elongation reveal genetic differences in two lines from upland cotton CCRI70 RIL population. PeerJ 2021; 9:e11812. [PMID: 34327061 PMCID: PMC8308610 DOI: 10.7717/peerj.11812] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 06/28/2021] [Indexed: 01/23/2023] Open
Abstract
Upland cotton is the most widely planted for natural fiber around the world, and either lint percentage (LP) or fiber length (FL) is the crucial component tremendously affecting cotton yield and fiber quality, respectively. In this study, two lines MBZ70-053 and MBZ70-236 derived from G. hirsutum CCRI70 recombinant inbred line (RIL) population presenting different phenotypes in LP and FL traits were chosen to conduct RNA sequencing on ovule and fiber samples, aiming at exploring the differences of molecular and genetic mechanisms during cotton fiber initiation and elongation stages. As a result, 249/128, 369/206, 4296/1198 and 3547/2129 up-/down- regulated differentially expressed genes (DGEs) in L2 were obtained at -3, 0, 5 and 10 days post-anthesis (DPA), respectively. Seven gene expression profiles were discriminated using Short Time-series Expression Miner (STEM) analysis; seven modules and hub genes were identified using weighted gene co-expression network analysis. The DEGs were mainly enriched into energetic metabolism and accumulating as well as auxin signaling pathway in initiation and elongation stages, respectively. Meanwhile, 29 hub genes were identified as 14-3-3ω , TBL35, GhACS, PME3, GAMMA-TIP, PUM-7, etc., where the DEGs and hub genes revealed the genetic and molecular mechanisms and differences during cotton fiber development.
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Affiliation(s)
- Xiao Jiang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Liqiang Fan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China.,School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Pengtao Li
- School of Biotechnology and Food Engineering, Anyang Institute of Technology, Anyang, Henan, China
| | - Xianyan Zou
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Zhen Zhang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Senmiao Fan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Juwu Gong
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China
| | - Youlu Yuan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China.,School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Haihong Shang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, China.,School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, China
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Liu F, Li JP, Li LS, Liu Q, Li SW, Song ML, Li S, Zhang Y. The canonical α-SNAP is essential for gametophytic development in Arabidopsis. PLoS Genet 2021; 17:e1009505. [PMID: 33886546 PMCID: PMC8096068 DOI: 10.1371/journal.pgen.1009505] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 05/04/2021] [Accepted: 03/24/2021] [Indexed: 12/26/2022] Open
Abstract
The development of male and female gametophytes is a pre-requisite for successful reproduction of angiosperms. Factors mediating vesicular trafficking are among the key regulators controlling gametophytic development. Fusion between vesicles and target membranes requires the assembly of a fusogenic soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs) complex, whose disassembly in turn ensures the recycle of individual SNARE components. The disassembly of post-fusion SNARE complexes is controlled by the AAA+ ATPase N-ethylmaleimide-sensitive factor (Sec18/NSF) and soluble NSF attachment protein (Sec17/α-SNAP) in yeast and metazoans. Although non-canonical α-SNAPs have been functionally characterized in soybeans, the biological function of canonical α-SNAPs has yet to be demonstrated in plants. We report here that the canonical α-SNAP in Arabidopsis is essential for male and female gametophytic development. Functional loss of the canonical α-SNAP in Arabidopsis results in gametophytic lethality by arresting the first mitosis during gametogenesis. We further show that Arabidopsis α-SNAP encodes two isoforms due to alternative splicing. Both isoforms interact with the Arabidopsis homolog of NSF whereas have distinct subcellular localizations. The presence of similar alternative splicing of human α-SNAP indicates that functional distinction of two α-SNAP isoforms is evolutionarily conserved.
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Affiliation(s)
- Fei Liu
- Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
| | - Ji-Peng Li
- State Key laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, China
| | - Lu-Shen Li
- State Key laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, China
| | - Qi Liu
- State Key laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, China
| | - Shan-Wei Li
- State Key laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, China
| | - Ming-Lei Song
- State Key laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, China
| | - Sha Li
- Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China
- State Key laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, China
- * E-mail: (SL); (YZ)
| | - Yan Zhang
- State Key laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, China
- * E-mail: (SL); (YZ)
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7
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Sun X, Cai X, Yin K, Gu L, Shen Y, Hu B, Wang Y, Chen Y, Zhu Y, Jia B, Sun M. Wild soybean SNARE proteins BET1s mediate the subcellular localization of the cytoplasmic receptor-like kinases CRCK1s to modulate salt stress responses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:771-785. [PMID: 33160290 DOI: 10.1111/tpj.15072] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/05/2020] [Accepted: 10/21/2020] [Indexed: 05/27/2023]
Abstract
Plants have evolved numerous receptor-like kinases (RLKs) that modulate environmental stress responses. However, little is known regarding soybean (Glycine max) RLKs. We have previously identified that Glycine soja Ca2+ /CAM-binding RLK (GsCBRLK) is involved in salt tolerance. Here, we report that soluble NSF attachment protein receptor proteins BET1s mediate subcellular localization of calmodulin-binding receptor-like cytoplasmic kinases CRCK1s to modulate salt stress responses. Direct interaction between GsCBRLK and GsBET11a was initially identified via yeast two-hybrid and bimolecular fluorescence complementation assays. Further analysis demonstrated conserved interaction between BET1s and CRCK1s. GsCBRLK interacted with all BET1 proteins in wild soybean (Glycine soja) and Arabidopsis, and GsBET11a strongly associated with GsCRCK1a-1d, but slightly with AtCRCK1. In addition, GsBET11a interacted with GsCBRLK via its C-terminal transmembrane domain (TMD), where the entire TMD, not the sequence, was critical for the interaction. Moreover, the N-terminal variable domain (VD) of GsCBRLK was responsible for interacting with GsBET11a, and the intensity of interaction between GsCBRLK/AtCRCK1 and GsBET11a was dependent on VD. Furthermore, GsBET11a was able to mediate the GsCBRLK subcellular localization via direct interaction with VD. Additionally, knockout of AtBET11 or AtBET12 individually did not alter GsCBRLK localization, while GsBET11a expression caused partial internalization of GsCBRLK from the plasma membrane (PM). We further suggest the necessity of GsCBRLK VD for its PM localization via N-terminal truncation assays. Finally, GsBET11a was shown to confer enhanced salt stress tolerance when overexpressed in Arabidopsis and soybean. These results revealed the conserved and direct interaction between BET1s and CRCK1s, and suggested their involvement in salt stress responses.
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Affiliation(s)
- Xiaoli Sun
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Xiaoxi Cai
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Kuide Yin
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Liwei Gu
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Yang Shen
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Bingshuang Hu
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Yan Wang
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Yue Chen
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Yanming Zhu
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Bowei Jia
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
| | - Mingzhe Sun
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China
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MARTINIÈRE A, MOREAU P. Complex roles of Rabs and SNAREs in the secretory pathway and plant development: a never‐ending story. J Microsc 2020; 280:140-157. [DOI: 10.1111/jmi.12952] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 07/22/2020] [Accepted: 07/31/2020] [Indexed: 12/14/2022]
Affiliation(s)
- A. MARTINIÈRE
- Univ Montpellier, CNRS, INRAE, Montpellier SupAgro BPMP Montpellier France
| | - P. MOREAU
- UMR 5200 Membrane Biogenesis Laboratory CNRS and University of Bordeaux, INRAE Bordeaux Villenave d'Ornon France
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Chung KP, Zeng Y, Li Y, Ji C, Xia Y, Jiang L. Signal motif-dependent ER export of the Qc-SNARE BET12 interacts with MEMB12 and affects PR1 trafficking in Arabidopsis. J Cell Sci 2018; 131:jcs.202838. [PMID: 28546447 DOI: 10.1242/jcs.202838] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/23/2017] [Indexed: 12/27/2022] Open
Abstract
Soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptors (SNAREs) are well-known for their role in controlling membrane fusion, the final, but crucial step, in vesicular transport in eukaryotes. SNARE proteins contribute to various biological processes including pathogen defense and channel activity regulation, as well as plant growth and development. Precise targeting of SNARE proteins to destined compartments is a prerequisite for their proper functioning. However, the underlying mechanism(s) for SNARE targeting in plants remains obscure. Here, we investigate the targeting mechanism of the Arabidopsis thaliana Qc-SNARE BET12, which is involved in protein trafficking in the early secretory pathway. Two distinct signal motifs that are required for efficient BET12 ER export were identified. Pulldown assays and in vivo imaging implicated that both the COPI and COPII pathways were required for BET12 targeting. Further studies using an ER-export-defective form of BET12 revealed that the Golgi-localized Qb-SNARE MEMB12, a negative regulator of pathogenesis-related protein 1 (PR1; At2g14610) secretion, was its interacting partner. Ectopic expression of BET12 caused no inhibition in the general ER-Golgi anterograde transport but caused intracellular accumulation of PR1, suggesting that BET12 has a regulatory role in PR1 trafficking in A. thaliana.
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Affiliation(s)
- Kin Pan Chung
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yonglun Zeng
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yimin Li
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Changyang Ji
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yiji Xia
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China .,The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China
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