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Wu YN, Lu JY, Li S, Zhang Y. Are vacuolar dynamics crucial factors for plant cell division and differentiation? PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2024; 344:112090. [PMID: 38636812 DOI: 10.1016/j.plantsci.2024.112090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/03/2024] [Accepted: 04/10/2024] [Indexed: 04/20/2024]
Abstract
Vacuoles are the largest membrane-bound organelles in plant cells, critical for development and environmental responses. Vacuolar dynamics indicate reversible changes of vacuoles in morphology, size, or numbers. In this review, we summarize current understandings of vacuolar dynamics in different types of plant cells, biological processes associated with vacuolar dynamics, and regulators controlling vacuolar dynamics. Specifically, we point out the possibility that vacuolar dynamics play key roles in cell division and differentiation, which are controlled by the nucleus. Finally, we propose three routes through which vacuolar dynamics actively participate in nucleus-controlled cellular activities.
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Affiliation(s)
- Ya-Nan Wu
- Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Jin-Yu Lu
- Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Sha Li
- College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China
| | - Yan Zhang
- Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin 300071, China.
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2
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Song C, Xie K, Chen H, Xu S, Mao H. Wheat ESCRT-III protein TaSAL1 regulates male gametophyte transmission and controls tillering and heading date. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2372-2384. [PMID: 38206130 DOI: 10.1093/jxb/erae012] [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: 08/16/2023] [Accepted: 01/10/2024] [Indexed: 01/12/2024]
Abstract
Charged multivesicular protein 1 (CHMP1) is a member of the endosomal sorting complex required for transport-III (ESCRT-III) complex that targets membrane localized signaling receptors to intralumenal vesicles in the multivesicular body of the endosome and eventually to the lysosome for degradation. Although CHMP1 plays roles in various plant growth and development processes, little is known about its function in wheat. In this study, we systematically analysed the members of the ESCRT-III complex in wheat (Triticum aestivum) and found that their orthologs were highly conserved in eukaryotic evolution. We identified CHMP1 homologous genes, TaSAL1s, and found that they were constitutively expressed in wheat tissues and essential for plant reproduction. Subcellular localization assays showed these proteins aggregated with and closely associated with the endoplasmic reticulum when ectopically expressed in tobacco leaves. We also found these proteins were toxic and caused leaf death. A genetic and reciprocal cross analysis revealed that TaSAL1 leads to defects in male gametophyte biogenesis. Moreover, phenotypic and metabolomic analysis showed that TaSAL1 may regulate tillering and heading date through phytohormone pathways. Overall, our results highlight the role of CHMP1 in wheat, particularly in male gametophyte biogenesis, with implications for improving plant growth and developing new strategies for plant breeding and genetic engineering.
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Affiliation(s)
- Chengxiang Song
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Kaidi Xie
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Hao Chen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Shuhao Xu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Hailiang Mao
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
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3
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Tabassum N, Ahmed HI, Parween S, Sheikh AH, Saad MM, Krattinger SG, Hirt H. Host genotype, soil composition, and geo-climatic factors shape the fonio seed microbiome. MICROBIOME 2024; 12:11. [PMID: 38233870 PMCID: PMC10792890 DOI: 10.1186/s40168-023-01725-5] [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: 04/05/2023] [Accepted: 11/18/2023] [Indexed: 01/19/2024]
Abstract
BACKGROUND Fonio (Digitaria exilis), an orphan millet crop, is the oldest indigenous crop in West Africa. Although the yield is low due to pre-domestication characteristics, the quick maturation time, drought tolerance, and the ability to thrive on poor soils make fonio a climate-smart crop. Being holobionts, plants evolve in close interaction with microbial partners, which is crucial for plant phenology and fitness. As seeds are the bottleneck of vertically transmitting plant microbiota, we proposed to unravel the seed microbiome of the under-domesticated and resilient crop fonio. Our study investigated the bacterial seed endophyte diversity across 126 sequenced fonio accessions from distinct locations in West Africa. We conducted a correlation study of the structures and functions of the seed-associated microbiomes with the native geo-climate and soil structure data. We also performed Genome-wide association studies (GWAS) to identify genetic loci associated with seed endophyte diversity. RESULT We report that fonio millet has diverse heritable seed endophytic taxa. We analyzed the seed microbiomes of 126 fonio accessions and showed that despite the diversity of microbiomes from distinct geographical locations, all fonio genetic groups share a core microbiome. In addition, we observed that native soil composition, geo-climatic factors, and host genotype correlate with the seed microbiomes. GWAS analysis of genetic loci associated with endophyte seed bacterial diversity identified fonio SNPs associated with genes functioning in embryo development and stress/defense response. CONCLUSION Analysis of the seed endophyte of the climate-smart crop fonio indicated that despite possessing a heritable core microbiome, native conditions may shape the overall fonio seed microbiomes in different populations. These distinct microbiomes could play important roles in the adaptation of fonio to different environmental conditions. Our study identified the seed microbiome as a potential target for enhancing crop resilience to climate stress in a sustainable way. Video Abstract.
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Affiliation(s)
- Naheed Tabassum
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia
- Center for Desert Agriculture, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia
| | - Hanin Ibrahim Ahmed
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia
- Center for Desert Agriculture, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia
| | - Sabiha Parween
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia
- Center for Desert Agriculture, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia
| | - Arsheed H Sheikh
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia
- Center for Desert Agriculture, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia
| | - Maged M Saad
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia.
- Center for Desert Agriculture, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia.
| | - Simon G Krattinger
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia.
- Center for Desert Agriculture, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia.
| | - Heribert Hirt
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia.
- Center for Desert Agriculture, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Saudi Arabia.
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4
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Zeng Y, Liang Z, Liu Z, Li B, Cui Y, Gao C, Shen J, Wang X, Zhao Q, Zhuang X, Erdmann PS, Wong KB, Jiang L. Recent advances in plant endomembrane research and new microscopical techniques. THE NEW PHYTOLOGIST 2023; 240:41-60. [PMID: 37507353 DOI: 10.1111/nph.19134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 06/19/2023] [Indexed: 07/30/2023]
Abstract
The endomembrane system consists of various membrane-bound organelles including the endoplasmic reticulum (ER), Golgi apparatus, trans-Golgi network (TGN), endosomes, and the lysosome/vacuole. Membrane trafficking between distinct compartments is mainly achieved by vesicular transport. As the endomembrane compartments and the machineries regulating the membrane trafficking are largely conserved across all eukaryotes, our current knowledge on organelle biogenesis and endomembrane trafficking in plants has mainly been shaped by corresponding studies in mammals and yeast. However, unique perspectives have emerged from plant cell biology research through the characterization of plant-specific regulators as well as the development and application of the state-of-the-art microscopical techniques. In this review, we summarize our current knowledge on the plant endomembrane system, with a focus on several distinct pathways: ER-to-Golgi transport, protein sorting at the TGN, endosomal sorting on multivesicular bodies, vacuolar trafficking/vacuole biogenesis, and the autophagy pathway. We also give an update on advanced imaging techniques for the plant cell biology research.
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Affiliation(s)
- 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
| | - Zizhen Liang
- 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
| | - Zhiqi Liu
- 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
| | - Baiying Li
- 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
| | - Yong Cui
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Jinbo Shen
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China
| | - Xiangfeng Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Qiong Zhao
- School of Life Sciences, East China Normal University, Shanghai, 200062, China
| | - Xiaohong Zhuang
- 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
| | - Philipp S Erdmann
- Human Technopole, Viale Rita Levi-Montalcini, 1, Milan, I-20157, Italy
| | - Kam-Bo Wong
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong (CUHK), Shatin, 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 CUHK Shenzhen Research Institute, Shenzhen, 518057, China
- Institute of Plant Molecular Biology and Agricultural Biotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
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Kong K, Xu M, Xu Z, Lv W, Lv P, Begum N, Liu B, Liu B, Zhao T. Dysfunction of GmVPS8a causes compact plant architecture in soybean. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 331:111677. [PMID: 36931563 DOI: 10.1016/j.plantsci.2023.111677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 03/12/2023] [Accepted: 03/14/2023] [Indexed: 06/18/2023]
Abstract
Vacuolar Protein Sorting 8 (Vps8) protein is a specific subunit of the class C core vacuole/endosome tethering (CORVET) complex that plays a key role in endosomal trafficking in yeast (Saccharomyces cerevisiae). However, its functions remain largely unclear in plant vegetative growth. Here, we identified a soybean (Glycine max) T4219 mutant characterized with compact plant architecture. Map-based cloning targeted to a candidate gene GmVPS8a (Glyma.07g049700) and further found that two nucleotides deletion in the first exon of GmVPS8a causes a premature termination of the encoded protein in the T4219 mutant. Its functions were validated by CRISPR/Cas9-engineered mutation in the GmVPS8a gene that recapitulated the T4219 mutant phenotypes. Furthermore, NbVPS8a-silenced tobacco (Nicotiana benthamiana) plants exhibited similar phenotypes to the T4219 mutant, suggesting its conserved roles in plant growth. The GmVPS8a is widely expressed in multiple organs and its protein interacts with GmAra6a and GmRab5a. Combined analysis of transcriptomic and proteomic data revealed that dysfunction of GmVPS8a mainly affects pathways on auxin signal transduction, sugar transport and metabolism, and lipid metabolism. Collectively, our work reveals the function of GmVPS8a in plant architecture, which may extend a new way for genetic improvement of ideal plant-architecture breeding in soybean and other crops.
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Affiliation(s)
- Keke Kong
- Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Mengge Xu
- Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhiyong Xu
- Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Wenhuan Lv
- Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Peiyun Lv
- Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Naheeda Begum
- Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Bingqiang Liu
- National Soybean Improvement Center Shijiazhuang Sub-Center, North China Key Laboratory of Biology and Genetic Improvement of Soybean, Ministry of Agriculture, Laboratory of Crop Genetics and Breeding of Hebei, Cereal & Oil Crop Institute, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang, China
| | - Bin Liu
- The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China.
| | - Tuanjie Zhao
- Soybean Research Institute, Key Laboratory of Biology and Genetic Improvement of Soybean, National Center for Soybean Improvement (Ministry of Agriculture), National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China.
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6
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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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Jiang D, He Y, Zhou X, Cao Z, Pang L, Zhong S, Jiang L, Li R. Arabidopsis HOPS subunit VPS41 carries out plant-specific roles in vacuolar transport and vegetative growth. PLANT PHYSIOLOGY 2022; 189:1416-1434. [PMID: 35417008 PMCID: PMC9237685 DOI: 10.1093/plphys/kiac167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 02/25/2022] [Indexed: 05/27/2023]
Abstract
The homotypic fusion and protein sorting (HOPS) complex is a conserved, multi-subunit tethering complex in eukaryotic cells. In yeast and mammalian cells, the HOPS subunit vacuolar protein sorting-associated protein 41 (VPS41) is recruited to late endosomes after Ras-related protein 7 (Rab7) activation and is essential for vacuole fusion. However, whether VPS41 plays conserved roles in plants is not clear. Here, we demonstrate that in the model plant Arabidopsis (Arabidopsis thaliana), VPS41 localizes to distinct condensates in root cells in addition to its reported localization at the tonoplast. The formation of condensates does not rely on the known upstream regulators but depends on VPS41 self-interaction and is essential for vegetative growth regulation. Genetic evidence indicates that VPS41 is required for both homotypic vacuole fusion and cargo sorting from the adaptor protein complex 3, Rab5, and Golgi-independent pathways but is dispensable for the Rab7 cargo inositol transporter 1. We also show that VPS41 has HOPS-independent functions in vacuolar transport. Taken together, our findings indicate that Arabidopsis VPS41 is a unique subunit of the HOPS complex that carries out plant-specific roles in both vacuolar transport and developmental regulation.
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Affiliation(s)
- Dong Jiang
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, School of Life Sciences, Institute of Plant and Food Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yilin He
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Xiangui Zhou
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, School of Life Sciences, Institute of Plant and Food Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Zhiran Cao
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, School of Life Sciences, Institute of Plant and Food Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Lei Pang
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, School of Life Sciences, Institute of Plant and Food Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Sheng Zhong
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at the College of Life Sciences, Peking University, Beijing 100871, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518172, China
| | - Ruixi Li
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, School of Life Sciences, Institute of Plant and Food Science, Southern University of Science and Technology, Shenzhen 518055, China
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Hao G, Zhao X, Zhang M, Ying J, Yu F, Li S, Zhang Y. Vesicle trafficking in
Arabidopsis
pollen tubes. FEBS Lett 2022; 596:2231-2242. [DOI: 10.1002/1873-3468.14343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/08/2022] [Accepted: 03/08/2022] [Indexed: 11/07/2022]
Affiliation(s)
- Guang‐Jiu Hao
- State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai’an, Shandong China
| | - Xin‐Ying Zhao
- State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai’an, Shandong China
| | | | - Jun Ying
- State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai’an, Shandong China
| | - Fei Yu
- State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai’an, Shandong China
| | - Sha Li
- State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai’an, Shandong China
| | - Yan Zhang
- State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai’an, Shandong China
- College of Life Sciences Nankai University China
- Frontiers Science Center for Cell Responses Nankai University China
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9
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Hou S, Shi J, Hao L, Wang Z, Liao Y, Gu H, Dong J, Dresselhaus T, Zhong S, Qu LJ. VPS18-regulated vesicle trafficking controls the secretion of pectin and its modifying enzyme during pollen tube growth in Arabidopsis. THE PLANT CELL 2021; 33:3042-3056. [PMID: 34125904 PMCID: PMC8462820 DOI: 10.1093/plcell/koab164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 06/03/2021] [Indexed: 05/07/2023]
Abstract
In eukaryotes, homotypic fusion and vacuolar protein sorting (HOPS) as well as class C core vacuole/endosome tethering (CORVET) are evolutionarily conserved membrane tethering complexes that play important roles in lysosomal/vacuolar trafficking. Whether HOPS and CORVET control endomembrane trafficking in pollen tubes, the fastest growing plant cells, remains largely elusive. In this study, we demonstrate that the four core components shared by the two complexes, Vacuole protein sorting 11 (VPS11), VPS16, VPS33, and VPS18, are all essential for pollen tube growth in Arabidopsis thaliana and thus for plant reproduction success. We used VPS18 as a representative core component of the complexes to show that the protein is localized to both multivesicular bodies (MVBs) and the tonoplast in a growing pollen tube. Mutant vps18 pollen tubes grew more slowly in vivo, resulting in a significant reduction in male transmission efficiency. Additional studies revealed that membrane fusion from MVBs to vacuoles is severely compromised in vps18 pollen tubes, corroborating the function of VPS18 in late endocytic trafficking. Furthermore, vps18 pollen tubes produce excessive exocytic vesicles at the apical zone and excessive amounts of pectin and pectin methylesterases in the cell wall. In conclusion, this study establishes an additional conserved role of HOPS/CORVET in homotypic membrane fusion during vacuole biogenesis in pollen tubes and reveals a feedback regulation of HOPS/CORVET in the secretion of cell wall modification enzymes of rapidly growing plant cells.
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Affiliation(s)
- Saiying Hou
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, People’s Republic of China
| | - Jiao Shi
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, People’s Republic of China
| | - Lihong Hao
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, People’s Republic of China
- School of Life Sciences, Shanxi University, Taiyuan, Shanxi Province 030006, People’s Republic of China
| | - Zhijuan Wang
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, People’s Republic of China
| | - Yalan Liao
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, People’s Republic of China
| | - Hongya Gu
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, People’s Republic of China
| | - Juan Dong
- The Waksman Institute of Microbiology, Rutgers the State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, University of Regensburg, 93053 Regensburg, Germany
| | - Sheng Zhong
- Author for correspondence: (S.Z.), (L.-J.Q.)
| | - Li-Jia Qu
- Author for correspondence: (S.Z.), (L.-J.Q.)
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Aslam M, Sugita K, Qin Y, Rahman A. Aux/IAA14 Regulates microRNA-Mediated Cold Stress Response in Arabidopsis Roots. Int J Mol Sci 2020; 21:E8441. [PMID: 33182739 PMCID: PMC7697755 DOI: 10.3390/ijms21228441] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/04/2020] [Accepted: 11/04/2020] [Indexed: 12/16/2022] Open
Abstract
The phytohormone auxin and microRNA-mediated regulation of gene expressions are key regulators of plant growth and development at both optimal and under low-temperature stress conditions. However, the mechanistic link between microRNA and auxin in regulating plant cold stress response remains elusive. To better understand the role of microRNA (miR) in the crosstalk between auxin and cold stress responses, we took advantage of the mutants of Arabidopsis thaliana with altered response to auxin transport and signal. Screening of the mutants for root growth recovery after cold stress at 4 °C revealed that the auxin signaling mutant, solitary root 1 (slr1; mutation in Aux/IAA14), shows a hypersensitive response to cold stress. Genome-wide expression analysis of miRs in the wild-type and slr1 mutant roots using next-generation sequencing revealed 180 known and 71 novel cold-responsive microRNAs. Cold stress also increased the abundance of 26-31 nt small RNA population in slr1 compared with wild type. Comparative analysis of microRNA expression shows significant differential expression of 13 known and 7 novel miRs in slr1 at 4 °C compared with wild type. Target gene expression analysis of the members from one potential candidate miR, miR169, revealed the possible involvement of miR169/NF-YA module in the Aux/IAA14-mediated cold stress response. Taken together, these results indicate that SLR/IAA14, a transcriptional repressor of auxin signaling, plays a crucial role in integrating miRs in auxin and cold responses.
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Affiliation(s)
- Mohammad Aslam
- Department of Plant Bio Sciences, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan; (M.A.); (K.S.)
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Lab of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning 530004, China;
- Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Center for Genomics and Biotechnology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Kenji Sugita
- Department of Plant Bio Sciences, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan; (M.A.); (K.S.)
| | - Yuan Qin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Lab of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning 530004, China;
- Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Center for Genomics and Biotechnology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Abidur Rahman
- Department of Plant Bio Sciences, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan; (M.A.); (K.S.)
- United Graduate School of Agricultural Sciences, Iwate University, Morioka 020-8550, Japan
- Agri-Innovation Center, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan
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11
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Jones SI, Hunt MR, Vodkin LO. An embryo lethal transgenic line manifests global expression changes and elevated protein/oil ratios in heterozygous soybean plants. PLoS One 2020; 15:e0233721. [PMID: 32516314 PMCID: PMC7282645 DOI: 10.1371/journal.pone.0233721] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 05/11/2020] [Indexed: 11/18/2022] Open
Abstract
Understanding the molecular processes of seed development is important especially in agronomic crops that produce large amounts of nutrient reserves. Because soybean is a vital source of vegetable protein worldwide, producers are concerned about increasing the total amount of protein in the seed without substantially lowering the amount of oil, another economically important product. Here we describe a transgenic soybean line with increased protein and protein/oil ratio, containing an average of 42.2% protein vs. 38.5% in controls and with a protein/oil ratio of 2.02 vs. 1.76 in controls over several generations of greenhouse growth. Other phenotypic data show that the seeds are heavier, although there are overall lower yields per plant. We postulate these effects result from insertion site mutagenesis by the transgenic construct. As this line never achieves homozygosity and appears to be embryo lethal when homozygous, one functional copy of the gene is most likely essential for normal seed development. Global transcript analyses using RNA-Seq for 88,000 gene models over two stages of cotyledon development revealed that more genes are over-expressed in the transgenic line including ribosomal protein related genes and those in the membrane protein and transporters families. Localization of the insertion site should reveal the genes and developmental program that has been perturbed by the transgenic construct, resulting in this economically interesting increase in protein and the protein/oil ratio.
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Affiliation(s)
- Sarah I. Jones
- Department of Crop Sciences, University of Illinois, Urbana, Illinois, United States of America
| | - Matt R. Hunt
- Department of Crop Sciences, University of Illinois, Urbana, Illinois, United States of America
| | - Lila O. Vodkin
- Department of Crop Sciences, University of Illinois, Urbana, Illinois, United States of America
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12
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Minamino N, Ueda T. RAB GTPases and their effectors in plant endosomal transport. CURRENT OPINION IN PLANT BIOLOGY 2019; 52:61-68. [PMID: 31454706 DOI: 10.1016/j.pbi.2019.07.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 07/18/2019] [Accepted: 07/23/2019] [Indexed: 06/10/2023]
Abstract
The plant endomembrane system comprises distinctive membrane-bounded organelles connected with one another by the membrane trafficking system. The RAB GTPase is a key component of the membrane trafficking machinery that regulates the targeting and tethering of trafficking vesicles to target compartments by acting as a molecular switch cycling between active and inactive states. The functions of RAB GTPases are fulfilled through their interactions with several classes of interacting factors, including guanine nucleotide exchange factors (GEFs) and effector proteins. Effector proteins for plant RAB GTPases consist of evolutionarily conserved and plant-unique factors, which are involved in various membrane trafficking events in plant cells in ways unique to plants. In this review, we summarize recent findings on the functions of endosomal RAB GTPases that underwent unique diversification during plant evolution, with a special focus on RAB5/RABF and RAB11/RABA.
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Affiliation(s)
- Naoki Minamino
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
| | - Takashi Ueda
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan; Department of Basic Biology, SOKENDAI (Graduate University of Advanced Studies), Okazaki, Aichi 444-8585, Japan.
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13
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Jiménez-López D, Muñóz-Belman F, González-Prieto JM, Aguilar-Hernández V, Guzmán P. Repertoire of plant RING E3 ubiquitin ligases revisited: New groups counting gene families and single genes. PLoS One 2018; 13:e0203442. [PMID: 30169501 PMCID: PMC6118397 DOI: 10.1371/journal.pone.0203442] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 08/21/2018] [Indexed: 01/12/2023] Open
Abstract
E3 ubiquitin ligases of the ubiquitin proteasome system (UPS) mediate recognition of substrates and later transfer the ubiquitin (Ub). They are the most expanded components of the system. The Really Interesting New Gene (RING) domain contains 40-60 residues that are highly represented among E3 ubiquitin ligases. The Arabidopsis thaliana E3 ubiquitin ligases with a RING finger primarily contain RING-HC or RING-H2 type domains or less frequently RING-v, RING-C2, RING-D, RING-S/T and RING-G type domains. Our previous work on three E3 ubiquitin ligase families with a RING-H2 type domain, ATL, BTL, and CTL, suggested that a phylogenetic distribution based on the RING domain allowed for the creation a catalog of known domains or unknown conserved motifs. This work provided a useful and comprehensive view of particular families of RING E3 ubiquitin ligases. We updated the annotation of A. thaliana RING proteins and surveyed RING proteins from 30 species across eukaryotes. Based on domain architecture profile of the A. thaliana proteins, we catalogued 4711 RING finger proteins into 107 groups, including 66 previously described gene families or single genes and 36 novel families or undescribed genes. Forty-four groups were specific to a plant lineage while 41 groups consisted of proteins found in all eukaryotic species. Our present study updates the current classification of plant RING finger proteins and reiterates the importance of these proteins in plant growth and adaptation.
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Affiliation(s)
- Domingo Jiménez-López
- Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del IPN, Unidad Irapuato, Irapuato, Gto., México
- Biotecnología Vegetal, Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Reynosa, Tamaulipas, México
| | - Francisco Muñóz-Belman
- Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del IPN, Unidad Irapuato, Irapuato, Gto., México
| | - Juan Manuel González-Prieto
- Biotecnología Vegetal, Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Reynosa, Tamaulipas, México
| | - Victor Aguilar-Hernández
- CONACYT, Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Col. Chuburná de Hidalgo, Mérida, Yucatán, México
| | - Plinio Guzmán
- Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del IPN, Unidad Irapuato, Irapuato, Gto., México
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14
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Phosphoinositides control the localization of HOPS subunit VPS41, which together with VPS33 mediates vacuole fusion in plants. Proc Natl Acad Sci U S A 2018; 115:E8305-E8314. [PMID: 30104351 DOI: 10.1073/pnas.1807763115] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The vacuole is an essential organelle in plant cells, and its dynamic nature is important for plant growth and development. Homotypic membrane fusion is required for vacuole biogenesis, pollen germination, stomata opening, and gravity perception. Known components of the vacuole fusion machinery in eukaryotes include SNARE proteins, Rab GTPases, phosphoinositides, and the homotypic fusion and vacuolar protein sorting (HOPS) tethering complex. HOPS function is not well characterized in plants, but roles in embryogenesis and pollen tube elongation have been reported. Here, we show that Arabidopsis HOPS subunits VPS33 and VPS41 accumulate in late endosomes and that VPS41, but not VPS33, accumulates in the tonoplast via a wortmannin-sensitive process. VPS41 and VPS33 proteins bind to liposomes, but this binding is inhibited by phosphatidylinosiltol-3-phosphate [PtdIns(3)P] and PtdIns(3,5)P2, which implicates a nonconserved mechanism for HOPS recruitment in plants. Inducible knockdown of VPS41 resulted in dramatic vacuole fragmentation phenotypes and demonstrated a critical role for HOPS in vacuole fusion. Furthermore, we provide evidence for genetic interactions between VPS41 and VTI11 SNARE that regulate vacuole fusion, and the requirement of a functional SNARE complex for normal VPS41 and VPS33 localization. Finally, we provide evidence to support VPS33 and SYP22 at the initial stage for HOPS-SNARE interactions, which is similar to other eukaryotes. These results highlight both conserved and specific mechanisms for HOPS recruitment and function during vacuole fusion in plants.
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15
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Sparvoli D, Richardson E, Osakada H, Lan X, Iwamoto M, Bowman GR, Kontur C, Bourland WA, Lynn DH, Pritchard JK, Haraguchi T, Dacks JB, Turkewitz AP. Remodeling the Specificity of an Endosomal CORVET Tether Underlies Formation of Regulated Secretory Vesicles in the Ciliate Tetrahymena thermophila. Curr Biol 2018; 28:697-710.e13. [PMID: 29478853 DOI: 10.1016/j.cub.2018.01.047] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 12/09/2017] [Accepted: 01/17/2018] [Indexed: 12/14/2022]
Abstract
In the endocytic pathway of animals, two related complexes, called CORVET (class C core vacuole/endosome transport) and HOPS (homotypic fusion and protein sorting), act as both tethers and fusion factors for early and late endosomes, respectively. Mutations in CORVET or HOPS lead to trafficking defects and contribute to human disease, including immune dysfunction. HOPS and CORVET are conserved throughout eukaryotes, but remarkably, in the ciliate Tetrahymena thermophila, the HOPS-specific subunits are absent, while CORVET-specific subunits have proliferated. VPS8 (vacuolar protein sorting), a CORVET subunit, expanded to 6 paralogs in Tetrahymena. This expansion correlated with loss of HOPS within a ciliate subgroup, including the Oligohymenophorea, which contains Tetrahymena. As uncovered via forward genetics, a single VPS8 paralog in Tetrahymena (VPS8A) is required to synthesize prominent secretory granules called mucocysts. More specifically, Δvps8a cells fail to deliver a subset of cargo proteins to developing mucocysts, instead accumulating that cargo in vesicles also bearing the mucocyst-sorting receptor Sor4p. Surprisingly, although this transport step relies on CORVET, it does not appear to involve early endosomes. Instead, Vps8a associates with the late endosomal/lysosomal marker Rab7, indicating that target specificity switching occurred in CORVET subunits during the evolution of ciliates. Mucocysts belong to a markedly diverse and understudied class of protist secretory organelles called extrusomes. Our results underscore that biogenesis of mucocysts depends on endolysosomal trafficking, revealing parallels with invasive organelles in apicomplexan parasites and suggesting that a wide array of secretory adaptations in protists, like in animals, depend on mechanisms related to lysosome biogenesis.
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Affiliation(s)
- Daniela Sparvoli
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | | | - Hiroko Osakada
- Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Kobe 651-2492, Japan
| | - Xun Lan
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
| | - Masaaki Iwamoto
- Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Kobe 651-2492, Japan
| | - Grant R Bowman
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | - Cassandra Kontur
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | - William A Bourland
- Department of Biological Sciences, Boise State University, Boise, ID 83725-1515, USA
| | - Denis H Lynn
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Jonathan K Pritchard
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Tokuko Haraguchi
- Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Kobe 651-2492, Japan; Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
| | - Joel B Dacks
- Department of Cell Biology, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Aaron P Turkewitz
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA.
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16
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Distinct sets of tethering complexes, SNARE complexes, and Rab GTPases mediate membrane fusion at the vacuole in Arabidopsis. Proc Natl Acad Sci U S A 2018; 115:E2457-E2466. [PMID: 29463724 PMCID: PMC5877921 DOI: 10.1073/pnas.1717839115] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Plant vacuoles play unique roles such as storage and coloring, in addition to lysosomal/vacuolar functions shared by eukaryotes: degradation and recycling of waste. To fulfill these complex and specialized functions, plant vacuolar trafficking occurs through multiple, uniquely regulated transport pathways. Two evolutionarily conserved tethering complexes, homotypic fusion and protein sorting (HOPS) and class C core vacuole/endosome tethering (CORVET), are involved in lysosomal/vacuolar trafficking in nonplant systems, although they also exist in plants. However, it remains almost entirely unknown how these tethering complexes regulate the unique aspects of plant vacuolar transport. Here, we show that HOPS and CORVET mediate distinct vacuolar trafficking pathways in coordination with different sets of soluble N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) proteins and RAB GTPase. Our findings provide further evidence for the unique evolutionary diversification of the vacuolar transport system in plants. Membrane trafficking plays pivotal roles in various cellular activities and higher-order functions of eukaryotes and requires tethering factors to mediate contact between transport intermediates and target membranes. Two evolutionarily conserved tethering complexes, homotypic fusion and protein sorting (HOPS) and class C core vacuole/endosome tethering (CORVET), are known to act in endosomal/vacuolar transport in yeast and animals. Both complexes share a core subcomplex consisting of Vps11, Vps18, Vps16, and Vps33, and in addition to this core, HOPS contains Vps39 and Vps41, whereas CORVET contains Vps3 and Vps8. HOPS and CORVET subunits are also conserved in the model plant Arabidopsis. However, vacuolar trafficking in plants occurs through multiple unique transport pathways, and how these conserved tethering complexes mediate endosomal/vacuolar transport in plants has remained elusive. In this study, we investigated the functions of VPS18, VPS3, and VPS39, which are core complex, CORVET-specific, and HOPS-specific subunits, respectively. Impairment of these tethering proteins resulted in embryonic lethality, distinctly altering vacuolar morphology and perturbing transport of a vacuolar membrane protein. CORVET interacted with canonical RAB5 and a plant-specific R-soluble NSF attachment protein receptor (SNARE), VAMP727, which mediates fusion between endosomes and the vacuole, whereas HOPS interacted with RAB7 and another R-SNARE, VAMP713, which likely mediates homotypic vacuolar fusion. These results indicate that CORVET and HOPS act in distinct vacuolar trafficking pathways in plant cells, unlike those of nonplant systems that involve sequential action of these tethering complexes during vacuolar/lysosomal trafficking. These results highlight a unique diversification of vacuolar/lysosomal transport that arose during plant evolution, using evolutionarily conserved tethering components.
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