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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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Xu L, Cao L, Li J, Staiger CJ. Cooperative actin filament nucleation by the Arp2/3 complex and formins maintains the homeostatic cortical array in Arabidopsis epidermal cells. THE PLANT CELL 2024; 36:764-789. [PMID: 38057163 PMCID: PMC10896301 DOI: 10.1093/plcell/koad301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/17/2023] [Accepted: 11/19/2023] [Indexed: 12/08/2023]
Abstract
Precise control over how and where actin filaments are created leads to the construction of unique cytoskeletal arrays within a common cytoplasm. Actin filament nucleators are key players in this activity and include the conserved actin-related protein 2/3 (Arp2/3) complex as well as a large family of formins. In some eukaryotic cells, these nucleators compete for a common pool of actin monomers and loss of one favors the activity of the other. To test whether this mechanism is conserved, we combined the ability to image single filament dynamics in the homeostatic cortical actin array of living Arabidopsis (Arabidopsis thaliana) epidermal cells with genetic and/or small molecule inhibitor approaches to stably or acutely disrupt nucleator activity. We found that Arp2/3 mutants or acute CK-666 treatment markedly reduced the frequency of side-branched nucleation events as well as overall actin filament abundance. We also confirmed that plant formins contribute to side-branched filament nucleation in vivo. Surprisingly, simultaneous inhibition of both classes of nucleator increased overall actin filament abundance and enhanced the frequency of de novo nucleation events by an unknown mechanism. Collectively, our findings suggest that multiple actin nucleation mechanisms cooperate to generate and maintain the homeostatic cortical array of plant epidermal cells.
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Affiliation(s)
- Liyuan Xu
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Lingyan Cao
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Jiejie Li
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Christopher J Staiger
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
- EMBRIO Institute, Purdue University, West Lafayette, IN 47907, USA
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3
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Zhang T, Bai L, Guo Y. SCAB1 coordinates sequential Ca 2+ and ABA signals during osmotic stress induced stomatal closure in Arabidopsis. SCIENCE CHINA. LIFE SCIENCES 2024; 67:1-18. [PMID: 38153680 DOI: 10.1007/s11427-023-2480-4] [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: 10/08/2023] [Accepted: 11/01/2023] [Indexed: 12/29/2023]
Abstract
Hyperosmotic stress caused by drought is a detrimental threat to plant growth and agricultural productivity due to limited water availability. Stomata are gateways of transpiration and gas exchange, the swift adjustment of stomatal aperture has a strong influence on plant drought resistance. Despite intensive investigations of stomatal closure during drought stress in past decades, little is known about how sequential signals are integrated during complete processes. Here, we discovered that the rapid Ca2+ signaling and subsequent abscisic acid (ABA) signaling contribute to the kinetics of both F-actin reorganizations and stomatal closure in Arabidopsis thaliana, while STOMATAL CLOSURE-RELATED ACTIN BINDING PROTEIN1 (SCAB1) is the molecular switch for this entire process. During the early stage of osmotic shock responses, swift elevated calcium signaling promotes SCAB1 phosphorylation through calcium sensors CALCIUM DEPENDENT PROTEIN KINASE3 (CPK3) and CPK6. The phosphorylation restrained the microfilament binding affinity of SCAB1, which bring about the F-actin disassembly and stomatal closure initiation. As the osmotic stress signal continued, both the kinase activity of CPK3 and the phosphorylation level of SCAB1 attenuated significantly. We further found that ABA signaling is indispensable for these attenuations, which presumably contributed to the actin filament reassembly process as well as completion of stomatal closure. Notably, the dynamic changes of SCAB1 phosphorylation status are crucial for the kinetics of stomatal closure. Taken together, our results support a model in which SCAB1 works as a molecular switch, and directs the microfilament rearrangement through integrating the sequentially generated Ca2+ and ABA signals during osmotic stress induced stomatal closure.
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Affiliation(s)
- Tianren Zhang
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Li Bai
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yan Guo
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
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4
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Hodgens C, Flaherty DT, Pullen AM, Khan I, English NJ, Gillan L, Rojas-Pierce M, Akpa BS. Model-based inference of a plant-specific dual role for HOPS in regulating guard cell vacuole fusion. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.07.565947. [PMID: 37986942 PMCID: PMC10659295 DOI: 10.1101/2023.11.07.565947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Stomata are the pores on a leaf surface that regulate gas exchange. Each stoma consists of two guard cells whose movements regulate pore opening and thereby control CO2 fixation and water loss. Guard cell movements depend in part on the remodeling of vacuoles, which have been observed to change from a highly fragmented state to a fused morphology during stomata opening. This change in morphology requires a membrane fusion mechanism that responds rapidly to environmental signals, allowing plants to respond to diurnal and stress cues. With guard cell vacuoles being both large and responsive to external signals, stomata represent a unique system in which to delineate mechanisms of membrane fusion. Fusion of vacuole membranes is a highly conserved process in eukaryotes, with key roles played by two multi-subunit complexes: HOPS (homotypic fusion and vacuolar protein sorting) and SNARE (soluble NSF attachment protein receptor). HOPS is a vacuole tethering factor that is thought to chaperone SNAREs from apposing vacuole membranes into a fusion-competent complex capable of rearranging membranes. To resolve a counter-intuitive observation regarding the role of HOPS in regulating plant vacuole morphology, we derived a quantitative model of vacuole fusion dynamics and used it to generate testable predictions about HOPS-SNARE interactions. We derived our model by applying simulation-based inference to integrate prior knowledge about molecular interactions with limited, qualitative observations of emergent vacuole phenotypes. By constraining the model parameters to yield the emergent outcomes observed for stoma opening - as induced by two distinct chemical treatments - we predicted a dual role for HOPS and identified a stalled form of the SNARE complex that differs from phenomena reported in yeast. We predict that HOPS has contradictory actions at different points in the fusion signaling pathway, promoting the formation of SNARE complexes, but limiting their activity.
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Affiliation(s)
- Charles Hodgens
- Department of Chemical and Biomolecular Engineering, University of Tennessee-Knoxville, Knoxville, Tennessee, USA
| | - DT Flaherty
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, North Carolina, USA
| | - Anne-Marie Pullen
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Imran Khan
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Nolan J English
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Lydia Gillan
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Marcela Rojas-Pierce
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Belinda S Akpa
- Department of Chemical and Biomolecular Engineering, University of Tennessee-Knoxville, Knoxville, Tennessee, USA
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, North Carolina, USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
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5
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Takatsuka H, Higaki T, Ito M. At the Nexus between Cytoskeleton and Vacuole: How Plant Cytoskeletons Govern the Dynamics of Large Vacuoles. Int J Mol Sci 2023; 24:ijms24044143. [PMID: 36835552 PMCID: PMC9967756 DOI: 10.3390/ijms24044143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/15/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023] Open
Abstract
Large vacuoles are a predominant cell organelle throughout the plant body. They maximally account for over 90% of cell volume and generate turgor pressure that acts as a driving force of cell growth, which is essential for plant development. The plant vacuole also acts as a reservoir for sequestering waste products and apoptotic enzymes, thereby enabling plants to rapidly respond to fluctuating environments. Vacuoles undergo dynamic transformation through repeated enlargement, fusion, fragmentation, invagination, and constriction, eventually resulting in the typical 3-dimensional complex structure in each cell type. Previous studies have indicated that such dynamic transformations of plant vacuoles are governed by the plant cytoskeletons, which consist of F-actin and microtubules. However, the molecular mechanism of cytoskeleton-mediated vacuolar modifications remains largely unclear. Here we first review the behavior of cytoskeletons and vacuoles during plant development and in response to environmental stresses, and then introduce candidates that potentially play pivotal roles in the vacuole-cytoskeleton nexus. Finally, we discuss factors hampering the advances in this research field and their possible solutions using the currently available cutting-edge technologies.
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Affiliation(s)
- Hirotomo Takatsuka
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
- Correspondence:
| | - Takumi Higaki
- Faculty of Advanced Science and Technology, Kumamoto University, Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
- International Research Organization for Advanced Science and Technology, Kumamoto University, Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - Masaki Ito
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
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Zhou J, Xiao L, Huang R, Song F, Li L, Li P, Fang Y, Lu W, Lv C, Quan M, Zhang D, Du Q. Local diversity of drought resistance and resilience in Populus tomentosa correlates with the variation of DNA methylation. PLANT, CELL & ENVIRONMENT 2023; 46:479-497. [PMID: 36385613 DOI: 10.1111/pce.14490] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/25/2022] [Accepted: 11/10/2022] [Indexed: 06/16/2023]
Abstract
Little information is known about DNA methylation variation in shaping environment-specific drought resistance and resilience for tree adaptation. In this study, we leveraged RNA sequencing and whole-genome bisulfite sequencing data to dissect the distinction of epigenetic regulation under drought stress and rewater condition of Populus tomentosa accessions from three geographical regions. We demonstrated low resistance and high resilience for accessions from South. Non-CG methylation levels in promoter regions of Southern accessions were lower than accessions from higher latitudes and negatively regulated gene expression. CHH context methylation was more sensitive to drought stress, and the geographical-specific differentially methylated regions were scarcely changed by environmental fluctuation. We identified 60 conserved hub genes within the co-expression networks that correlate with photosynthetic and stomatal morphological traits. Epigenome-wide association studies and genome-wide association studies of these 60 hub genes revealed the interdependency between genetic and epigenetic variation in GATA9 and LECRK-VIII.2, which was associated with stomatal morphology and chlorophyll content. The natural epigenetic variation in GATA9 was also faithfully transmitted to progenies in two family-based F1 populations. This study indicates a functional relationship of DNA methylation diversity with drought resistance and resilience which offers new insights into plants' local adaptation to a stressful environment.
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Affiliation(s)
- Jiaxuan Zhou
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Liang Xiao
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Rui Huang
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Fangyuan Song
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Lianzheng Li
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Peng Li
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Yuanyuan Fang
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Wenjie Lu
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Chenfei Lv
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Mingyang Quan
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Deqiang Zhang
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
| | - Qingzhang Du
- National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
- The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China
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7
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Ge S, Zhang RX, Wang YF, Sun P, Chu J, Li J, Sun P, Wang J, Hetherington AM, Liang YK. The Arabidopsis Rab protein RABC1 affects stomatal development by regulating lipid droplet dynamics. THE PLANT CELL 2022; 34:4274-4292. [PMID: 35929087 PMCID: PMC9614440 DOI: 10.1093/plcell/koac239] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 07/13/2022] [Indexed: 05/13/2023]
Abstract
Lipid droplets (LDs) are evolutionarily conserved organelles that serve as hubs of cellular lipid and energy metabolism in virtually all organisms. Mobilization of LDs is important in light-induced stomatal opening. However, whether and how LDs are involved in stomatal development remains unknown. We show here that Arabidopsis thaliana LIPID DROPLETS AND STOMATA 1 (LDS1)/RABC1 (At1g43890) encodes a member of the Rab GTPase family that is involved in regulating LD dynamics and stomatal morphogenesis. The expression of RABC1 is coordinated with the different phases of stomatal development. RABC1 targets to the surface of LDs in response to oleic acid application in a RABC1GEF1-dependent manner. RABC1 physically interacts with SEIPIN2/3, two orthologues of mammalian seipin, which function in the formation of LDs. Disruption of RABC1, RABC1GEF1, or SEIPIN2/3 resulted in aberrantly large LDs, severe defects in guard cell vacuole morphology, and stomatal function. In conclusion, these findings reveal an aspect of LD function and uncover a role for lipid metabolism in stomatal development in plants.
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Affiliation(s)
| | | | - Yi-Fei Wang
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan 430072, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Pengyue Sun
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan 430072, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Jiaheng Chu
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Jiao Li
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Peng Sun
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Jianbo Wang
- State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Alistair M Hetherington
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
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8
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Biel A, Moser M, Groves NR, Meier I. Distinct Roles for KASH Proteins SINE1 and SINE2 in Guard Cell Actin Reorganization, Calcium Oscillations, and Vacuolar Remodeling. FRONTIERS IN PLANT SCIENCE 2022; 13:784342. [PMID: 35599883 PMCID: PMC9120628 DOI: 10.3389/fpls.2022.784342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 04/06/2022] [Indexed: 06/15/2023]
Abstract
The linker of nucleoskeleton and cytoskeleton (LINC) complex is a protein complex spanning the inner and outer membranes of the nuclear envelope. Outer nuclear membrane KASH proteins interact in the nuclear envelope lumen with inner nuclear membrane SUN proteins. The paralogous Arabidopsis KASH proteins SINE1 and SINE2 function during stomatal dynamics induced by light-dark transitions and ABA. Previous studies have shown F-actin organization, cytoplasmic calcium (Ca2+) oscillations, and vacuolar morphology changes are involved in ABA-induced stomatal closure. Here, we show that SINE1 and SINE2 are both required for actin pattern changes during ABA-induced stomatal closure, but influence different, temporally distinguishable steps. External Ca2+ partially overrides the mutant defects. ABA-induced cytoplasmic Ca2+ oscillations are diminished in sine2-1 but not sine1-1, and this defect can be rescued by both exogenous Ca2+ and F-actin depolymerization. We show first evidence for nuclear Ca2+ oscillations during ABA-induced stomatal closure, which are disrupted in sine2-1. Vacuolar fragmentation is impaired in both mutants and is partially rescued by F-actin depolymerization. Together, these data indicate distinct roles for SINE1 and SINE2 upstream of this network of players involved in ABA-based stomatal closure, suggesting a role for the nuclear surface in guard cell ABA signaling.
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Affiliation(s)
- Alecia Biel
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, United States
| | - Morgan Moser
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, United States
| | - Norman R. Groves
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, United States
- Center for Applied Plant Sciences, The Ohio State University, Columbus, OH, United States
| | - Iris Meier
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, United States
- Center for Applied Plant Sciences, The Ohio State University, Columbus, OH, United States
- Center for RNA Biology, The Ohio State University, Columbus, OH, United States
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9
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Cao W, Li Z, Huang S, Shi Y, Zhu Y, Lai MN, Lok PL, Wang X, Cui Y, Jiang L. Correlation of vacuole morphology with stomatal lineage development by whole-cell electron tomography. PLANT PHYSIOLOGY 2022; 188:2085-2100. [PMID: 35134219 PMCID: PMC8968265 DOI: 10.1093/plphys/kiac028] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 12/22/2021] [Indexed: 05/26/2023]
Abstract
Stomatal movement is essential for plants to optimize transpiration and therefore photosynthesis. Rapid changes in the stomatal aperture are accompanied by adjustment of vacuole volume and morphology in guard cells (GCs). In Arabidopsis (Arabidopsis thaliana) leaf epidermis, stomatal development undergoes a cell-fate transition including four stomatal lineage cells: meristemoid, guard mother cell, young GC, and GC. Little is known about the mechanism underlying vacuole dynamics and vacuole formation during stomatal development. Here, we utilized whole-cell electron tomography (ET) analysis to elucidate vacuole morphology, formation, and development in different stages of stomatal lineage cells at nanometer resolution. The whole-cell ET models demonstrated that large vacuoles were generated from small vacuole stepwise fusion/maturation along stomatal development stages. Further ET analyses verified the existence of swollen intraluminal vesicles inside distinct vacuoles at certain developmental stages of stomatal lineage cells, implying a role of multivesicular body fusion in stomatal vacuole formation. Collectively, our findings demonstrate a mechanism mediating vacuole formation in Arabidopsis stomatal development and may shed light on the role of vacuoles in stomatal movement.
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Affiliation(s)
- Wenhan Cao
- 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
| | - Zhenping 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
| | - Shuxian Huang
- 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
| | - Yuwei Shi
- 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
| | - Ying Zhu
- 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
| | - Man Nga Lai
- 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
| | - Pui Lok Lok
- 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
| | - Xiangfeng Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yong Cui
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
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10
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Kang BH, Anderson CT, Arimura SI, Bayer E, Bezanilla M, Botella MA, Brandizzi F, Burch-Smith TM, Chapman KD, Dünser K, Gu Y, Jaillais Y, Kirchhoff H, Otegui MS, Rosado A, Tang Y, Kleine-Vehn J, Wang P, Zolman BK. A glossary of plant cell structures: Current insights and future questions. THE PLANT CELL 2022; 34:10-52. [PMID: 34633455 PMCID: PMC8846186 DOI: 10.1093/plcell/koab247] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/29/2021] [Indexed: 05/03/2023]
Abstract
In this glossary of plant cell structures, we asked experts to summarize a present-day view of plant organelles and structures, including a discussion of outstanding questions. In the following short reviews, the authors discuss the complexities of the plant cell endomembrane system, exciting connections between organelles, novel insights into peroxisome structure and function, dynamics of mitochondria, and the mysteries that need to be unlocked from the plant cell wall. These discussions are focused through a lens of new microscopy techniques. Advanced imaging has uncovered unexpected shapes, dynamics, and intricate membrane formations. With a continued focus in the next decade, these imaging modalities coupled with functional studies are sure to begin to unravel mysteries of the plant cell.
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Affiliation(s)
- Byung-Ho Kang
- 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
| | - Charles T Anderson
- Department of Biology and Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, Pennsylvania 16802 USA
| | - Shin-ichi Arimura
- Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | - Emmanuelle Bayer
- Université de Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire, UMR 5200, Villenave d'Ornon F-33140, France
| | - Magdalena Bezanilla
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA
| | - Miguel A Botella
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortifruticultura Subtropical y Mediterránea “La Mayora,” Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Universidad de Málaga, Málaga 29071, Spain
| | - Federica Brandizzi
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, Michigan 48824 USA
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824, USA
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan 48824, USA
| | - Tessa M Burch-Smith
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Kent D Chapman
- BioDiscovery Institute and Department of Biological Sciences, University of North Texas, Denton, Texas 76203, USA
| | - Kai Dünser
- Faculty of Biology, Chair of Molecular Plant Physiology (MoPP) University of Freiburg, Freiburg 79104, Germany
- Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, Freiburg 79104, Germany
| | - Yangnan Gu
- Department of Plant and Microbial Biology, Innovative Genomics Institute, University of California, Berkeley, California 94720, USA
| | - Yvon Jaillais
- Laboratoire Reproduction et Développement des Plantes (RDP), Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, Lyon, France
| | - Helmut Kirchhoff
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164, USA
| | - Marisa S Otegui
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Wisconsin 53706, USA
| | - Abel Rosado
- Department of Botany, University of British Columbia, Vancouver V6T1Z4, Canada
| | - Yu Tang
- Department of Plant and Microbial Biology, Innovative Genomics Institute, University of California, Berkeley, California 94720, USA
| | - Jürgen Kleine-Vehn
- Faculty of Biology, Chair of Molecular Plant Physiology (MoPP) University of Freiburg, Freiburg 79104, Germany
- Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, Freiburg 79104, Germany
| | - Pengwei Wang
- Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Bethany Karlin Zolman
- Department of Biology, University of Missouri, St. Louis, St. Louis, Missouri 63121, USA
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11
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Yang Y, Zhao Y, Zheng W, Zhao Y, Zhao S, Wang Q, Bai L, Zhang T, Huang S, Song C, Yuan M, Guo Y. Phosphatidylinositol 3-phosphate regulates SCAB1-mediated F-actin reorganization during stomatal closure in Arabidopsis. THE PLANT CELL 2022; 34:477-494. [PMID: 34850207 PMCID: PMC8773959 DOI: 10.1093/plcell/koab264] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 10/22/2021] [Indexed: 05/20/2023]
Abstract
Stomatal movement is critical for plant responses to environmental changes and is regulated by the important signaling molecule phosphatidylinositol 3-phosphate (PI3P). However, the molecular mechanism underlying this process is not well understood. In this study, we show that PI3P binds to stomatal closure-related actin-binding protein1 (SCAB1), a plant-specific F-actin-binding and -bundling protein, and inhibits the oligomerization of SCAB1 to regulate its activity on F-actin in guard cells during stomatal closure in Arabidopsis thaliana. SCAB1 binds specifically to PI3P, but not to other phosphoinositides. Treatment with wortmannin, an inhibitor of phosphoinositide kinase that generates PI3P, leads to an increase of the intermolecular interaction and oligomerization of SCAB1, stabilization of F-actin, and retardation of F-actin reorganization during abscisic acid (ABA)-induced stomatal closure. When the binding activity of SCAB1 to PI3P is abolished, the mutated proteins do not rescue the stability and realignment of F-actin regulated by SCAB1 and the stomatal closure in the scab1 mutant. The expression of PI3P biosynthesis genes is consistently induced when the plants are exposed to drought and ABA treatments. Furthermore, the binding of PI3P to SCAB1 is also required for vacuolar remodeling during stomatal closure. Our results illustrate a PI3P-regulated pathway during ABA-induced stomatal closure, which involves the mediation of SCAB1 activity in F-actin reorganization.
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Affiliation(s)
| | | | | | - Yang Zhao
- Shanghai Center for Plant Stress Biology, CAS Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Shuangshuang Zhao
- Key Life Science College, Laboratory of Plant Stress, Shandong Normal University, Jinan 250014, China
| | - Qiannan Wang
- School of Life Sciences, Center for Plant Biology, Tsinghua University, Beijing 100084, China
| | - Li Bai
- College of Biological Sciences, State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing 100193, China
| | - Tianren Zhang
- College of Biological Sciences, State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing 100193, China
| | - Shanjin Huang
- School of Life Sciences, Center for Plant Biology, Tsinghua University, Beijing 100084, China
| | - Chunpeng Song
- Collaborative Innovation Center of Crop Stress Biology, Henan Province, Institute of Plant Stress Biology, Henan University, Kaifeng 475001, China
| | - Ming Yuan
- College of Biological Sciences, State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing 100193, China
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12
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Jiang YT, Yang LH, Ferjani A, Lin WH. Multiple functions of the vacuole in plant growth and fruit quality. MOLECULAR HORTICULTURE 2021; 1:4. [PMID: 37789408 PMCID: PMC10509827 DOI: 10.1186/s43897-021-00008-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 04/09/2021] [Indexed: 10/05/2023]
Abstract
Vacuoles are organelles in plant cells that play pivotal roles in growth and developmental regulation. The main functions of vacuoles include maintaining cell acidity and turgor pressure, regulating the storage and transport of substances, controlling the transport and localization of key proteins through the endocytic and lysosomal-vacuolar transport pathways, and responding to biotic and abiotic stresses. Further, proteins localized either in the tonoplast (vacuolar membrane) or inside the vacuole lumen are critical for fruit quality. In this review, we summarize and discuss some of the emerging functions and regulatory mechanisms associated with plant vacuoles, including vacuole biogenesis, vacuole functions in plant growth and development, fruit quality, and plant-microbe interaction, as well as some innovative research technology that has driven advances in the field. Together, the functions of plant vacuoles are important for plant growth and fruit quality. The investigation of vacuole functions in plants is of great scientific significance and has potential applications in agriculture.
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Affiliation(s)
- Yu-Tong Jiang
- Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Joint Center for Single Cell Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lu-Han Yang
- Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Joint Center for Single Cell Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei University, Koganei-shi, 184-8501, Japan
| | - Wen-Hui Lin
- Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Joint Center for Single Cell Biology, Shanghai Jiao Tong University, Shanghai, 200240, China.
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13
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Gong L, Liu XD, Zeng YY, Tian XQ, Li YL, Turner NC, Fang XW. Stomatal morphology and physiology explain varied sensitivity to abscisic acid across vascular plant lineages. PLANT PHYSIOLOGY 2021; 186:782-797. [PMID: 33620497 PMCID: PMC8154066 DOI: 10.1093/plphys/kiab090] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 01/28/2021] [Indexed: 05/10/2023]
Abstract
Abscisic acid (ABA) can induce rapid stomatal closure in seed plants, but the action of this hormone on the stomata of fern and lycophyte species remains equivocal. Here, ABA-induced stomatal closure, signaling components, guard cell K+ and Ca2+ fluxes, vacuolar and actin cytoskeleton dynamics, and the permeability coefficient of guard cell protoplasts (Pf) were analyzed in species spanning the diversity of vascular land plants including 11 seed plants, 6 ferns, and 1 lycophyte. We found that all 11 seed plants exhibited ABA-induced stomatal closure, but the fern and lycophyte species did not. ABA-induced hydrogen peroxide elevation was observed in all species, but the signaling pathway downstream of nitric oxide production, including ion channel activation, was only observed in seed plants. In the angiosperm faba bean (Vicia faba), ABA application caused large vacuolar compartments to disaggregate, actin filaments to disintegrate into short fragments and Pf to increase. None of these changes was observed in the guard cells of the fern Matteuccia struthiopteris and lycophyte Selaginella moellendorffii treated with ABA, but a hypertonic osmotic solution did induce stomatal closure in fern and the lycophyte. Our results suggest that there is a major difference in the regulation of stomata between the fern and lycophyte plants and the seed plants. Importantly, these findings have uncovered the physiological and biophysical mechanisms that may have been responsible for the evolution of a stomatal response to ABA in the earliest seed plants.
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Affiliation(s)
- Lei Gong
- State Key Laboratory of Grassland Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xu-Dong Liu
- State Key Laboratory of Grassland Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Yuan-Yuan Zeng
- State Key Laboratory of Grassland Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xue-Qian Tian
- State Key Laboratory of Grassland Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Yan-Lu Li
- State Key Laboratory of Grassland Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Neil C Turner
- The UWA Institute of Agriculture and UWA School of Agriculture and Environment, The University of Western Australia, M082, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Xiang-Wen Fang
- State Key Laboratory of Grassland Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
- Author for communication: (X.W.F.)
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14
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Wang ZQ, Liu Q, Wu JH, Li J, He JM, Zhang Y, Li S. Downregulating VAC14 in Guard Cells Causes Drought Hypersensitivity by Inhibiting Stomatal Closure. FRONTIERS IN PLANT SCIENCE 2020; 11:602701. [PMID: 33391314 PMCID: PMC7773697 DOI: 10.3389/fpls.2020.602701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/27/2020] [Indexed: 06/12/2023]
Abstract
Stomata are a key land plant innovation that permit the regulation of gaseous exchanges between the plant interior and the surrounding environment. By opening or closing, stomata regulate transpiration of water though the plant; and these actions are coordinated with acquisition of CO2 for photosynthesis. Stomatal movement is controlled by various environmental and physiological factors and associates with multiple intracellular activities, among which the dynamic remodeling of vacuoles plays a crucial role. Phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] is critical for dynamic remodeling of vacuoles. Its production requires a PI(3,5)P2-metabolizing complex consisting of FAB1/PIKfyve kinases, SAC phosphatases, and the scaffolding protein VAC14. Although genetic or pharmacological downregulation of PI(3,5)P2 causes hyposensitivity to ABA-induced stomatal closure, whether the effect of PI(3,5)P2 on stomatal movement is cell-autonomous and the physiological consequences of its reduction were unclear. We report that downregulating Arabidopsis VAC14 specifically in guard cells by artificial microRNAs (amiR-VAC14) results in enlarged guard cells and hyposensitivity to ABA- and dark-induced stomatal closure. Vacuolar fission during stomatal closure is compromised by downregulating VAC14 in guard cells. Exogenous application of PI(3,5)P2 rescued the amiR-VAC14 phenotype whereas PI(3,5)P2 inhibitor YM201636 caused wild-type plants to have inhibited stomatal closure. We further show that downregulating VAC14 specifically in guard cells impairs drought tolerance, suggestive of a key role of guard cell-produced PI(3,5)P2 in plant fitness.
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Affiliation(s)
- Zong-Qi Wang
- 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
| | - Ju-Hua Wu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Juan Li
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Jun-Min He
- School of Life Sciences, Shaanxi Normal University, Xi'an, China
| | - Yan Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Sha Li
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China
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15
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Shitan N, Yazaki K. Dynamism of vacuoles toward survival strategy in plants. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183127. [DOI: 10.1016/j.bbamem.2019.183127] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/27/2019] [Accepted: 11/01/2019] [Indexed: 02/08/2023]
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16
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Abstract
The genetic control of the characteristic cell sizes of different species and tissues is a long-standing enigma. Plants are convenient for studying this question in a multicellular context, as their cells do not move and are easily tracked and measured from organ initiation in the meristems to subsequent morphogenesis and differentiation. In this article, we discuss cell size control in plants compared with other organisms. As seen from yeast cells to mammalian cells, size homeostasis is maintained cell autonomously in the shoot meristem. In developing organs, vacuolization contributes to cell size heterogeneity and may resolve conflicts between growth control at the cellular and organ levels. Molecular mechanisms for cell size control have implications for how cell size responds to changes in ploidy, which are particularly important in plant development and evolution. We also discuss comparatively the functional consequences of cell size and their potential repercussions at higher scales, including genome evolution.
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Affiliation(s)
- Marco D'Ario
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Robert Sablowski
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
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17
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AP3M harbors actin filament binding activity that is crucial for vacuole morphology and stomatal closure in Arabidopsis. Proc Natl Acad Sci U S A 2019; 116:18132-18141. [PMID: 31431522 DOI: 10.1073/pnas.1901431116] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Stomatal movement is essential for plant growth. This process is precisely regulated by various cellular activities in guard cells. F-actin dynamics and vacuole morphology are both involved in stomatal movement. The sorting of cargoes by clathrin adaptor protein (AP) complexes from the Golgi to the vacuole is critical for establishing a normal vacuole morphology. In this study, we demonstrate that the medium subunit of the AP3 complex (AP3M) binds to and severs actin filaments in vitro and that it participates in the sorting of cargoes (such as the sucrose exporter SUC4) to the tonoplast, and thereby regulates stomatal closure in Arabidopsis thaliana Defects in AP3 or SUC4 led to more rapid water loss and delayed stomatal closure, as well as hypersensitivity to drought stress. In ap3m mutants, the F-actin status was altered compared to the wild type, and the sorted cargoes failed to localize to the tonoplast. AP3M contains a previously unidentified F-actin binding domain that is conserved in AP3M homologs in both plants and animals. Mutations in the F-actin binding domain of AP3M abolished its F-actin binding activity in vitro, leading to an aberrant vacuole morphology and reduced levels of SUC4 on the tonoplast in guard cells. Our findings indicate that the F-actin binding activity of AP3M is required for the precise localization of AP3-dependent cargoes to the tonoplast and for the regulation of vacuole morphology in guard cells during stomatal closure.
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18
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Li X, Diao M, Zhang Y, Chen G, Huang S, Chen N. Guard Cell Microfilament Analyzer Facilitates the Analysis of the Organization and Dynamics of Actin Filaments in Arabidopsis Guard Cells. Int J Mol Sci 2019; 20:ijms20112753. [PMID: 31195605 PMCID: PMC6600335 DOI: 10.3390/ijms20112753] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/26/2019] [Accepted: 05/28/2019] [Indexed: 11/29/2022] Open
Abstract
The actin cytoskeleton is involved in regulating stomatal movement, which forms distinct actin arrays within guard cells of stomata with different apertures. How those actin arrays are formed and maintained remains largely unexplored. Elucidation of the dynamic behavior of differently oriented actin filaments in guard cells will enhance our understanding in this regard. Here, we initially developed a program called ‘guard cell microfilament analyzer’ (GCMA) that enables the selection of individual actin filaments and analysis of their orientations semiautomatically in guard cells. We next traced the dynamics of individual actin filaments and performed careful quantification in open and closed stomata. We found that de novo nucleation of actin filaments occurs at both dorsal and ventral sides of guard cells from open and closed stomata. Interestingly, most of the nucleated actin filaments elongate radially and longitudinally in open and closed stomata, respectively. Strikingly, radial filaments tend to form bundles whereas longitudinal filaments tend to be removed by severing and depolymerization in open stomata. By contrast, longitudinal filaments tend to form bundles that are severed less frequently in closed stomata. These observations provide insights into the formation and maintenance of distinct actin arrays in guard cells in stomata of different apertures.
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Affiliation(s)
- Xin Li
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Min Diao
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
- iHuman Institute, Shanghai Tech University, Shanghai 201210, China.
| | - Yanan Zhang
- OLYMPUS (CHINA) CO., LTD, Beijing 100027, China.
| | - Guanlin Chen
- Baidu Online Network Technology (Beijing) CO., LTD, Beijing 100193, China.
| | - Shanjin Huang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
| | - Naizhi Chen
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
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19
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Huang L, Chen L, Wang L, Yang Y, Rao Y, Ren D, Dai L, Gao Y, Zou W, Lu X, Zhang G, Zhu L, Hu J, Chen G, Shen L, Dong G, Gao Z, Guo L, Qian Q, Zeng D. A Nck-associated protein 1-like protein affects drought sensitivity by its involvement in leaf epidermal development and stomatal closure in rice. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 98:884-897. [PMID: 30771248 PMCID: PMC6849750 DOI: 10.1111/tpj.14288] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 02/09/2019] [Accepted: 02/13/2019] [Indexed: 05/05/2023]
Abstract
Water deficit is a major environmental threat affecting crop yields worldwide. In this study, a drought stress-sensitive mutant drought sensitive 8 (ds8) was identified in rice (Oryza sativa L.). The DS8 gene was cloned using a map-based approach. Further analysis revealed that DS8 encoded a Nck-associated protein 1 (NAP1)-like protein, a component of the SCAR/WAVE complex, which played a vital role in actin filament nucleation activity. The mutant exhibited changes in leaf cuticle development. Functional analysis revealed that the mutation of DS8 increased stomatal density and impaired stomatal closure activity. The distorted actin filaments in the mutant led to a defect in abscisic acid (ABA)-mediated stomatal closure and increased ABA accumulation. All these resulted in excessive water loss in ds8 leaves. Notably, antisense transgenic lines also exhibited increased drought sensitivity, along with impaired stomatal closure and elevated ABA levels. These findings suggest that DS8 affects drought sensitivity by influencing actin filament activity.
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Affiliation(s)
- Lichao Huang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Long Chen
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Lan Wang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Yaolong Yang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Yuchun Rao
- College of Chemistry and Life SciencesZhejiang Normal UniversityJinhua321004China
| | - Deyong Ren
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Liping Dai
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Yihong Gao
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Weiwei Zou
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Xueli Lu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Guangheng Zhang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Li Zhu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Jiang Hu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Guang Chen
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Lan Shen
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Guojun Dong
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Zhenyu Gao
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Longbiao Guo
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Qian Qian
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
| | - Dali Zeng
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhou310006China
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20
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Agurla S, Gahir S, Munemasa S, Murata Y, Raghavendra AS. Mechanism of Stomatal Closure in Plants Exposed to Drought and Cold Stress. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1081:215-232. [PMID: 30288712 DOI: 10.1007/978-981-13-1244-1_12] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Drought is one of the abiotic stresses which impairs the plant growth/development and restricts the yield of many crops throughout the world. Stomatal closure is a common adaptation response of plants to the onset of drought condition. Stomata are microscopic pores on the leaf epidermis, which regulate the transpiration/CO2 uptake by leaves. Stomatal guard cells can sense various abiotic and biotic stress stimuli from the internal and external environment and respond quickly to initiate closure under unfavorable conditions. Stomata also limit the entry of pathogens into leaves, restricting their invasion. Drought is accompanied by the production and/or mobilization of the phytohormone, abscisic acid (ABA), which is well-known for its ability to induce stomatal closure. Apart from the ABA, various other factors that accumulate during drought and affect the stomatal function are plant hormones (auxins, MJ, ethylene, brassinosteroids, and cytokinins), microbial elicitors (salicylic acid, harpin, Flg 22, and chitosan), and polyamines . The role of various signaling components/secondary messengers during stomatal opening or closure has been a matter of intense investigation. Reactive oxygen species (ROS) , nitric oxide (NO) , cytosolic pH, and calcium are some of the well-documented signaling components during stomatal closure. The interrelationship and interactions of these signaling components such as ROS, NO, cytosolic pH, and free Ca2+ are quite complex and need further detailed examination.Low temperatures can have deleterious effects on plants. However, plants evolved protection mechanisms to overcome the impact of this stress. Cold temperature inhibits stomatal opening and causes stomatal closure. Cold-acclimated plants often exhibit marked changes in their lipid composition, particularly of the membranes. Cold stress often leads to the accumulation of ABA, besides osmolytes such as glycine betaine and proline. The role of signaling components such as ROS, NO, and Ca2+ during cold acclimation is yet to be established, though the effects of cold stress on plant growth and development are studied extensively. The information on the mitigation processes is quite limited. We have attempted to describe consequences of drought and cold stress in plants, emphasizing stomatal closure. Several of these factors trigger signaling components in roots, shoots, and atmosphere, all leading to stomatal closure. A scheme is presented to show the possible signaling events and their convergence and divergence of action during stomatal closure. The possible directions for future research are discussed.
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Affiliation(s)
- Srinivas Agurla
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Shashibhushan Gahir
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Shintaro Munemasa
- Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Yoshiyuki Murata
- Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan.
| | - Agepati S Raghavendra
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, India.
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21
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Baluška F, Mancuso S. Actin Cytoskeleton and Action Potentials: Forgotten Connections. THE CYTOSKELETON 2019. [DOI: 10.1007/978-3-030-33528-1_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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22
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Akita K, Hasezawa S, Higaki T. Cortical microtubules and fusicoccin response in clustered stomatal guard cells induced by sucrose solution immersion. PLANT SIGNALING & BEHAVIOR 2018; 13:e1454815. [PMID: 29557717 PMCID: PMC5933904 DOI: 10.1080/15592324.2018.1454815] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 03/15/2018] [Accepted: 03/16/2018] [Indexed: 05/29/2023]
Abstract
We previously found that sucrose solution immersion treatment permitted ectopic guard cell differentiation, resulting in clustered stomatal guard cells. Using this system, we examined the effects of sucrose solution-induced stomatal clustering on guard cell cortical microtubules and the stomatal response to fusicoccin. Confocal observation revealed that the radial orientation of cortical microtubules was largely maintained in clustered guard cells. Outward movement of cortical microtubule plus-ends was also kept in the clustered guard cells. Fusicoccin treatment induced stomatal opening in both spaced and clustered stomata, although sucrose solution-treated guard cells had lower stomatal apertures. These results suggested that immersion treatment with sucrose solution perturbed the one-cell spacing of stomata but not the cortical microtubule organization required to open stomatal pores.
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Affiliation(s)
- Kae Akita
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Japan
| | - Seiichiro Hasezawa
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Japan
| | - Takumi Higaki
- International Research Organization for Advanced Science and Technology, Kumamoto University, Kurokami, Chuo-ku, Kumamoto, Japan
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Enrique Gomez R, Joubès J, Valentin N, Batoko H, Satiat-Jeunemaître B, Bernard A. Lipids in membrane dynamics during autophagy in plants. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1287-1299. [PMID: 29140451 DOI: 10.1093/jxb/erx392] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/09/2017] [Indexed: 05/19/2023]
Abstract
Autophagy is a critical pathway for plant adaptation to stress. Macroautophagy relies on the biogenesis of a specialized membrane named the phagophore that maturates into a double membrane vesicle. Proteins and lipids act synergistically to promote membrane structure and functions, yet research on autophagy has mostly focused on autophagy-related proteins while knowledge of supporting lipids in the formation of autophagic membranes remains scarce. This review expands on studies in plants with examples from other organisms to present and discuss our current understanding of lipids in membrane dynamics associated with the autophagy pathway in plants.
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Affiliation(s)
- Rodrigo Enrique Gomez
- CNRS, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
- Université de Bordeaux, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
| | - Jérôme Joubès
- CNRS, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
- Université de Bordeaux, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
| | - Nicolas Valentin
- Institute for Integrative Biology of the Cell (I2BC), CNRS, CEA, Paris-Sud University, Avenue de la Terrasse, Gif-sur-Yvette, France
| | - Henri Batoko
- Institut des Sciences de la Vie, Université catholique de Louvain, Croix du Sud 4-L7.07.14, Louvain-la-Neuve, Belgium
| | - Béatrice Satiat-Jeunemaître
- Institute for Integrative Biology of the Cell (I2BC), CNRS, CEA, Paris-Sud University, Avenue de la Terrasse, Gif-sur-Yvette, France
| | - Amélie Bernard
- CNRS, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
- Université de Bordeaux, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
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24
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Abstract
In plant cells, vacuoles are extremely important for growth and development, and influence important cellular functions as photosynthesis, respiration, and transpiration. Plant cells contain lytic and storage vacuoles, whose size can be different depending on cell type and tissue developmental stage. One of the main roles of vacuoles is to regulate the cell turgor in response to different stimuli. Thus, studying the morphology, dynamics, and physiology of vacuole is fundamentally important to advance knowledge in plant cell biology at large. The availability of fluorescent probes allows marking vacuoles in multiple ways. These may be fast, when using commercially available chemical dyes, or relatively slow, in the case of specific genetically encoded markers based on proteins directed either to the membrane of the vacuole (tonoplast) or to the vacuole lumen. Any of these approaches provides useful information about the morphology and physiology of the vacuole.
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25
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Yu Q, Ren JJ, Kong LJ, Wang XL. Actin filaments regulate the adhesion between the plasma membrane and the cell wall of tobacco guard cells. PROTOPLASMA 2018; 255:235-245. [PMID: 28803402 DOI: 10.1007/s00709-017-1149-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 07/24/2017] [Indexed: 06/07/2023]
Abstract
During the opening and closing of stomata, guard cells undergo rapid and reversible changes in their volume and shape, which affects the adhesion of the plasma membrane (PM) to the cell wall (CW). The dynamics of actin filaments in guard cells are involved in stomatal movement by regulating structural changes and intracellular signaling. However, it is unclear whether actin dynamics regulate the adhesion of the PM to the CW. In this study, we investigated the relationship between actin dynamics and PM-CW adhesion by the hyperosmotic-induced plasmolysis of tobacco guard cells. We found that actin filaments in guard cells were depolymerized during mannitol-induced plasmolysis. The inhibition of actin dynamics by treatment with latrunculin B or jasplakinolide and the disruption of the adhesion between the PM and the CW by treatment with RGDS peptide (Arg-Gly-Asp-Ser) enhanced guard cell plasmolysis. However, treatment with latrunculin B alleviated the RGDS peptide-induced plasmolysis and endocytosis. Our results reveal that the actin depolymerization is involved in the regulation of the PW-CW adhesion during hyperosmotic-induced plasmolysis in tobacco guard cells.
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Affiliation(s)
- Qin Yu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China
| | - Jing-Jing Ren
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China
| | - Lan-Jing Kong
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China
| | - Xiu-Ling Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China.
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26
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Gujas B, Cruz TMD, Kastanaki E, Vermeer JEM, Munnik T, Rodriguez-Villalon A. Perturbing phosphoinositide homeostasis oppositely affects vascular differentiation in Arabidopsis thaliana roots. Development 2017; 144:3578-3589. [PMID: 28851711 PMCID: PMC5665488 DOI: 10.1242/dev.155788] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 08/18/2017] [Indexed: 01/16/2023]
Abstract
The plant vascular network consists of specialized phloem and xylem elements that undergo two distinct morphogenetic developmental programs to become transport-functional units. Whereas vacuolar rupture is a determinant step in protoxylem differentiation, protophloem elements never form a big central vacuole. Here, we show that a genetic disturbance of phosphatidylinositol 4,5-bis-phosphate [PtdIns(4,5)P2] homeostasis rewires cell trafficking towards the vacuole in Arabidopsis thaliana roots. Consequently, an enhanced phosphoinositide-mediated vacuolar biogenesis correlates with premature programmed cell death (PCD) and secondary cell wall elaboration in xylem cells. By contrast, vacuolar fusion events in protophloem cells trigger the abnormal formation of big vacuoles, preventing cell clearance and tissue functionality. Removal of the inositol 5' phosphatase COTYLEDON VASCULAR PATTERN 2 from the plasma membrane (PM) by brefeldin A (BFA) treatment increases PtdIns(4,5)P2 content at the PM and disrupts protophloem continuity. Conversely, BFA application abolishes vacuolar fusion events in xylem tissue without preventing PCD, suggesting the existence of additional PtdIns(4,5)P2-dependent cell death mechanisms. Overall, our data indicate that tight PM phosphoinositide homeostasis is required to modulate intracellular trafficking contributing to oppositely regulate vascular differentiation.
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Affiliation(s)
- Bojan Gujas
- Department of Biology, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092, Zurich, Switzerland
| | - Tiago M D Cruz
- Department of Biology, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092, Zurich, Switzerland
| | - Elizabeth Kastanaki
- Department of Biology, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092, Zurich, Switzerland
| | - Joop E M Vermeer
- Department of Plant and Microbial Biology, University of Zurich, CH-8008, Zurich, Switzerland
| | - Teun Munnik
- Section Plant Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1090 GE, Amsterdam, The Netherlands
| | - Antia Rodriguez-Villalon
- Department of Biology, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092, Zurich, Switzerland
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27
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Krüger F, Schumacher K. Pumping up the volume - vacuole biogenesis in Arabidopsis thaliana. Semin Cell Dev Biol 2017; 80:106-112. [PMID: 28694113 DOI: 10.1016/j.semcdb.2017.07.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/06/2017] [Accepted: 07/06/2017] [Indexed: 01/05/2023]
Abstract
Plant architecture follows the need to collect CO2, solar energy, water and mineral nutrients via large surface areas. It is by the presence of a central vacuole that fills much of the cell volume that plants manage to grow at low metabolic cost. In addition vacuoles buffer the fluctuating supply of essential nutrients and help to detoxify the cytosol when plants are challenged by harmful molecules. Despite their large size and multiple important functions, our knowledge of vacuole biogenesis and the machinery underlying their amazing dynamics is still fragmentary. In this review, we try to reconcile past and present models for vacuole biogenesis with the current knowledge of multiple parallel vacuolar trafficking pathways and the molecular machineries driving membrane fusion and organelle shape.
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Affiliation(s)
- Falco Krüger
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, DE-69120 Heidelberg, Germany
| | - Karin Schumacher
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, DE-69120 Heidelberg, Germany.
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28
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Zhao S, Jiang Y, Zhao Y, Huang S, Yuan M, Zhao Y, Guo Y. CASEIN KINASE1-LIKE PROTEIN2 Regulates Actin Filament Stability and Stomatal Closure via Phosphorylation of Actin Depolymerizing Factor. THE PLANT CELL 2016; 28:1422-39. [PMID: 27268429 PMCID: PMC4944410 DOI: 10.1105/tpc.16.00078] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 06/06/2016] [Indexed: 05/03/2023]
Abstract
The opening and closing of stomata are crucial for plant photosynthesis and transpiration. Actin filaments undergo dynamic reorganization during stomatal closure, but the underlying mechanism for this cytoskeletal reorganization remains largely unclear. In this study, we identified and characterized Arabidopsis thaliana casein kinase 1-like protein 2 (CKL2), which responds to abscisic acid (ABA) treatment and participates in ABA- and drought-induced stomatal closure. Although CKL2 does not bind to actin filaments directly and has no effect on actin assembly in vitro, it colocalizes with and stabilizes actin filaments in guard cells. Further investigation revealed that CKL2 physically interacts with and phosphorylates actin depolymerizing factor 4 (ADF4) and inhibits its activity in actin filament disassembly. During ABA-induced stomatal closure, deletion of CKL2 in Arabidopsis alters actin reorganization in stomata and renders stomatal closure less sensitive to ABA, whereas deletion of ADF4 impairs the disassembly of actin filaments and causes stomatal closure to be more sensitive to ABA Deletion of ADF4 in the ckl2 mutant partially recues its ABA-insensitive stomatal closure phenotype. Moreover, Arabidopsis ADFs from subclass I are targets of CKL2 in vitro. Thus, our results suggest that CKL2 regulates actin filament reorganization and stomatal closure mainly through phosphorylation of ADF.
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Affiliation(s)
- Shuangshuang Zhao
- Key Laboratory of Plant Stress, Life Science College, Shandong Normal University, Jinan 250014, China State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yuxiang Jiang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Science, Beijing 100093, China
| | - Yang Zhao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Shanjin Huang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Science, Beijing 100093, China Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ming Yuan
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yanxiu Zhao
- Key Laboratory of Plant Stress, Life Science College, Shandong Normal University, Jinan 250014, China
| | - Yan Guo
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
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29
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Hong D, Jeon BW, Kim SY, Hwang JU, Lee Y. The ROP2-RIC7 pathway negatively regulates light-induced stomatal opening by inhibiting exocyst subunit Exo70B1 in Arabidopsis. THE NEW PHYTOLOGIST 2016; 209:624-35. [PMID: 26451971 DOI: 10.1111/nph.13625] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 07/30/2015] [Indexed: 05/03/2023]
Abstract
Stomata are the tiny valves on the plant surface that mediate gas exchange between the plant and its environment. Stomatal opening needs to be tightly regulated to facilitate CO2 uptake and prevent excess water loss. Plant Rho-type (ROP) GTPase 2 (ROP2) is a molecular component of the system that negatively regulates light-induced stomatal opening. Previously, ROP-interactive Cdc42- and Rac-interactive binding motif-containing protein 7 (RIC7) was suggested to function downstream of ROP2. However, the underlying molecular mechanism remains unknown. To understand the mechanism by which RIC7 regulates light-induced stomatal opening, we analyzed the stomatal responses of ric7 mutant Arabidopsis plants and identified the target protein of RIC7 using a yeast two-hybrid screen. Light-induced stomatal opening was promoted by ric7 knockout, whereas it was inhibited by RIC7 overexpression, indicating that RIC7 negatively regulates stomatal opening in Arabidopsis. RIC7 interacted with exocyst subunit Exo70 family protein B1 (Exo70B1), a component of the vesicle trafficking machinery. RIC7 and Exo70B1 localized to the plasma membrane region under light or constitutively active ROP2 conditions. The knockout mutant of Exo70B1 and ric7/exo70b1 exhibited retarded light-induced stomatal opening. Our results suggest that ROP2 and RIC7 suppress excess stomatal opening by inhibiting Exo70B1, which most likely participates in the vesicle trafficking required for light-induced stomatal opening.
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Affiliation(s)
- Daewoong Hong
- Division of Molecular Life Sciences, POSTECH, Pohang, 790-784, Korea
| | - Byeong Wook Jeon
- Division of Molecular Life Sciences, POSTECH, Pohang, 790-784, Korea
| | - Soo Young Kim
- Departments of Molecular Biotechnology and Kumho Life Science Laboratory, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 500-757, Korea
| | - Jae-Ung Hwang
- Division of Molecular Life Sciences, POSTECH, Pohang, 790-784, Korea
| | - Youngsook Lee
- Division of Molecular Life Sciences, POSTECH, Pohang, 790-784, Korea
- Division of Integrative Biosciences and Biotechnology, POSTECH, Pohang, 790-784, Korea
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30
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Allyl Isothiocyanate Inhibits Actin-Dependent Intracellular Transport in Arabidopsis thaliana. Int J Mol Sci 2015; 16:29134-47. [PMID: 26690132 PMCID: PMC4691101 DOI: 10.3390/ijms161226154] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 11/12/2015] [Accepted: 11/20/2015] [Indexed: 12/21/2022] Open
Abstract
Volatile allyl isothiocyanate (AITC) derives from the biodegradation of the glucosinolate sinigrin and has been associated with growth inhibition in several plants, including the model plant Arabidopsis thaliana. However, the underlying cellular mechanisms of this feature remain scarcely investigated in plants. In this study, we present evidence of an AITC-induced inhibition of actin-dependent intracellular transport in A. thaliana. A transgenic line of A. thaliana expressing yellow fluorescent protein (YFP)-tagged actin filaments was used to show attenuation of actin filament movement by AITC. This appeared gradually in a time- and dose-dependent manner and resulted in actin filaments appearing close to static. Further, we employed four transgenic lines with YFP-fusion proteins labeling the Golgi apparatus, endoplasmic reticulum (ER), vacuoles and peroxisomes to demonstrate an AITC-induced inhibition of actin-dependent intracellular transport of or, in these structures, consistent with the decline in actin filament movement. Furthermore, the morphologies of actin filaments, ER and vacuoles appeared aberrant following AITC-exposure. However, AITC-treated seedlings of all transgenic lines tested displayed morphologies and intracellular movements similar to that of the corresponding untreated and control-treated plants, following overnight incubation in an AITC-absent environment, indicating that AITC-induced decline in actin-related movements is a reversible process. These findings provide novel insights into the cellular events in plant cells following exposure to AITC, which may further expose clues to the physiological significance of the glucosinolate-myrosinase system.
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31
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Zhang C, Hicks GR, Raikhel NV. Plant vacuole morphology and vacuolar trafficking. FRONTIERS IN PLANT SCIENCE 2014; 5:476. [PMID: 25309565 PMCID: PMC4173805 DOI: 10.3389/fpls.2014.00476] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 08/29/2014] [Indexed: 05/23/2023]
Abstract
Plant vacuoles are essential organelles for plant growth and development, and have multiple functions. Vacuoles are highly dynamic and pleiomorphic, and their size varies depending on the cell type and growth conditions. Vacuoles compartmentalize different cellular components such as proteins, sugars, ions and other secondary metabolites and play critical roles in plants response to different biotic/abiotic signaling pathways. In this review, we will summarize the patterns of changes in vacuole morphology in certain cell types, our understanding of the mechanisms of plant vacuole biogenesis, and the role of SNAREs and Rab GTPases in vacuolar trafficking.
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Affiliation(s)
- Chunhua Zhang
- *Correspondence: Chunhua Zhang, Center for Plant Cell Biology and Department of Botany and Plant Sciences, University of California at Riverside, 900 University Avenue, Riverside, CA 92521, USA e-mail:
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32
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McLachlan DH, Kopischke M, Robatzek S. Gate control: guard cell regulation by microbial stress. THE NEW PHYTOLOGIST 2014; 203:1049-1063. [PMID: 25040778 DOI: 10.1111/nph.12916] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 05/26/2014] [Indexed: 05/07/2023]
Abstract
Terrestrial plants rely on stomata, small pores in the leaf surface, for photosynthetic gas exchange and transpiration of water. The stomata, formed by a pair of guard cells, dynamically increase and decrease their volume to control the pore size in response to environmental cues. Stresses can trigger similar or opposing movements: for example, drought induces closure of stomata, whereas many pathogens exploit stomata and cause them to open to facilitate entry into plant tissues. The latter is an active process as stomatal closure is part of the plant's immune response. Stomatal research has contributed much to clarify the signalling pathways of abiotic stress, but guard cell signalling in response to microbes is a relatively new area of research. In this article, we discuss present knowledge of stomatal regulation in response to microbes and highlight common points of convergence, and differences, compared to stomatal regulation by abiotic stresses. We also expand on the mechanisms by which pathogens manipulate these processes to promote disease, for example by delivering effectors to inhibit closure or trigger opening of stomata. The study of pathogen effectors in stomatal manipulation will aid our understanding of guard cell signalling.
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Affiliation(s)
| | | | - Silke Robatzek
- The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH, UK
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33
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DePaoli HC, Borland AM, Tuskan GA, Cushman JC, Yang X. Synthetic biology as it relates to CAM photosynthesis: challenges and opportunities. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:3381-93. [PMID: 24567493 DOI: 10.1093/jxb/eru038] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
To meet future food and energy security needs, which are amplified by increasing population growth and reduced natural resource availability, metabolic engineering efforts have moved from manipulating single genes/proteins to introducing multiple genes and novel pathways to improve photosynthetic efficiency in a more comprehensive manner. Biochemical carbon-concentrating mechanisms such as crassulacean acid metabolism (CAM), which improves photosynthetic, water-use, and possibly nutrient-use efficiency, represent a strategic target for synthetic biology to engineer more productive C3 crops for a warmer and drier world. One key challenge for introducing multigene traits like CAM onto a background of C3 photosynthesis is to gain a better understanding of the dynamic spatial and temporal regulatory events that underpin photosynthetic metabolism. With the aid of systems and computational biology, vast amounts of experimental data encompassing transcriptomics, proteomics, and metabolomics can be related in a network to create dynamic models. Such models can undergo simulations to discover key regulatory elements in metabolism and suggest strategic substitution or augmentation by synthetic components to improve photosynthetic performance and water-use efficiency in C3 crops. Another key challenge in the application of synthetic biology to photosynthesis research is to develop efficient systems for multigene assembly and stacking. Here, we review recent progress in computational modelling as applied to plant photosynthesis, with attention to the requirements for CAM, and recent advances in synthetic biology tool development. Lastly, we discuss possible options for multigene pathway construction in plants with an emphasis on CAM-into-C3 engineering.
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Affiliation(s)
- Henrique C DePaoli
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6422, USA
| | - Anne M Borland
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6422, USA School of Biology, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK
| | - Gerald A Tuskan
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6422, USA
| | - John C Cushman
- Department of Biochemistry and Molecular Biology, MS330, University of Nevada, Reno, NV 89557-0330, USA
| | - Xiaohan Yang
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6422, USA
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34
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Zheng J, Han SW, Rodriguez-Welsh MF, Rojas-Pierce M. Homotypic vacuole fusion requires VTI11 and is regulated by phosphoinositides. MOLECULAR PLANT 2014; 7:1026-1040. [PMID: 24569132 DOI: 10.1093/mp/ssu019] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Most plant cells contain a large central vacuole that is essential to maintain cellular turgor. We report a new mutant allele of VTI11 that implicates the SNARE protein VTI11 in homotypic fusion of protein storage and lytic vacuoles. Fusion of the multiple vacuoles present in vti11 mutants could be induced by treatment with Wortmannin and LY294002, which are inhibitors of Phosphatidylinositol 3-Kinase (PI3K). We provide evidence that Phosphatidylinositol 3-Phosphate (PtdIns(3)P) regulates vacuole fusion in vti11 mutants, and that fusion of these vacuoles requires intact microtubules and actin filaments. Finally, we show that Wortmannin also induced the fusion of guard cell vacuoles in fava beans, where vacuoles are naturally fragmented after ABA-induced stomata closure. These results suggest a ubiquitous role of phosphoinositides in vacuole fusion, both during the development of the large central vacuole and during the dynamic vacuole remodeling that occurs as part of stomata movements.
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Affiliation(s)
- Jiameng Zheng
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Sang Won Han
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA
| | | | - Marcela Rojas-Pierce
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA.
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35
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Zepeda I, Sánchez-López R, Kunkel JG, Bañuelos LA, Hernández-Barrera A, Sánchez F, Quinto C, Cárdenas L. Visualization of highly dynamic F-actin plus ends in growing phaseolus vulgaris root hair cells and their responses to Rhizobium etli nod factors. PLANT & CELL PHYSIOLOGY 2014; 55:580-592. [PMID: 24399235 DOI: 10.1093/pcp/pct202] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Legume plants secrete signaling molecules called flavonoids into the rhizosphere. These molecules activate the transcription of rhizobial nod genes, which encode proteins involved in the synthesis of signaling compounds named Nod factors (NFs). NFs, in turn, trigger changes in plant gene expression, cortical cell dedifferentiation and mitosis, depolarization of the root hair cell membrane potential and rearrangement of the actin cytoskeleton. Actin polymerization plays an important role in apical growth in hyphae and pollen tubes. Using sublethal concentrations of fluorescently labeled cytochalasin D (Cyt-Fl), we visualized the distribution of filamentous actin (F-actin) plus ends in living Phaseolus vulgaris and Arabidopsis root hairs during apical growth. We demonstrated that Cyt-Fl specifically labeled the newly available plus ends of actin microfilaments, which probably represent sites of polymerization. The addition of unlabeled competing cytochalasin reduced the signal, suggesting that the labeled and unlabeled forms of the drug bind to the same site on F-actin. Exposure to Rhizobium etli NFs resulted in a rapid increase in the number of F-actin plus ends in P. vulgaris root hairs and in the re-localization of F-actin plus ends to infection thread initiation sites. These data suggest that NFs promote the formation of F-actin plus ends, which results in actin cytoskeleton rearrangements that facilitate infection thread formation.
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Affiliation(s)
- Isaac Zepeda
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, UNAM, Apdo. Postal 510-3, Cuernavaca, Morelos 62250, Mexico
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36
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Li LJ, Ren F, Gao XQ, Wei PC, Wang XC. The reorganization of actin filaments is required for vacuolar fusion of guard cells during stomatal opening in Arabidopsis. PLANT, CELL & ENVIRONMENT 2013; 36:484-97. [PMID: 22891733 DOI: 10.1111/j.1365-3040.2012.02592.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The reorganization of actin filaments (AFs) and vacuoles in guard cells is involved in the regulation of stomatal movement. However, it remains unclear whether there is any interaction between the reorganization of AFs and vacuolar changes during stomatal movement. Here, we report the relationship between the reorganization of AFs and vacuolar fusion revealed in pharmacological experiments, and characterizing stomatal opening in actin-related protein 2 (arp2) and arp3 mutants. Our results show that cytochalasin-D-induced depolymerization or phalloidin-induced stabilization of AFs leads to an increase in small unfused vacuoles during stomatal opening in wild-type (WT) Arabidopsis plants. Light-induced stomatal opening is retarded and vacuolar fusion in guard cells is impaired in the mutants, in which the reorganization and the dynamic parameters of AFs are aberrant compared with those of the WT. In WT, AFs tightly surround the small separated vacuoles, forming a ring that encircles the boundary membranes of vacuoles partly fused during stomatal opening. In contrast, in the mutants, most AFs and actin patches accumulate abnormally around the nuclei of the guard cells, which probably further impair vacuolar fusion and retard stomatal opening. Our results suggest that the reorganization of AFs regulates vacuolar fusion in guard cells during stomatal opening.
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Affiliation(s)
- Li-Juan Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
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37
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Martinoia E, Meyer S, De Angeli A, Nagy R. Vacuolar transporters in their physiological context. ANNUAL REVIEW OF PLANT BIOLOGY 2012; 63:183-213. [PMID: 22404463 DOI: 10.1146/annurev-arplant-042811-105608] [Citation(s) in RCA: 152] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Vacuoles in vegetative tissues allow the plant surface to expand by accumulating energetically cheap inorganic osmolytes, and thereby optimize the plant for absorption of sunlight and production of energy by photosynthesis. Some specialized cells, such as guard cells and pulvini motor cells, exhibit rapid volume changes. These changes require the rapid release and uptake of ions and water by the vacuole and are a prerequisite for plant survival. Furthermore, seed vacuoles are important storage units for the nutrients required for early plant development. All of these fundamental processes rely on numerous vacuolar transporters. During the past 15 years, the transporters implicated in most aspects of vacuolar function have been identified and characterized. Vacuolar transporters appear to be integrated into a regulatory network that controls plant metabolism. However, little is known about the mode of action of these fundamental processes, and deciphering the underlying mechanisms remains a challenge for the future.
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Affiliation(s)
- Enrico Martinoia
- Institute of Plant Biology, University of Zurich, Zurich, Switzerland.
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Chu CP, Liu ZH, Hu ZY, Wang XL. Tubular actin filaments in tobacco guard cells. PLANT SIGNALING & BEHAVIOR 2011; 6:1578-80. [PMID: 21921692 PMCID: PMC3256388 DOI: 10.4161/psb.6.10.17095] [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: 06/23/2011] [Accepted: 07/03/2011] [Indexed: 05/31/2023]
Abstract
The dynamic remodeling of actin filaments in guard cells functions in stomatal movement regulation. In our previous study, we found that the stochastic dynamics of guard cell actin filaments play a role in chloroplast movement during stomatal movement. In our present study, we further find that tubular actin filaments are present in tobacco guard cells that express GFP-mouse talin; approximately 2.3 tubular structures per cell with a diameter and height in the range of 1-3 µm and 3-5 µm, respectively. Most of the tubular structures were found to be localized in the cytoplasm near the inner walls of the guard cells. Moreover, the tubular actin filaments altered their localization slowly in the guard cells of static stoma, but showed obvious remodeling, such as breakdown and re-formation, in moving guard cells. Tubular actin filaments were further found to be colocalized with the chloroplasts in guard cells, but their roles in stomatal movement regulation requires further investigation.
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Affiliation(s)
- Cui-Ping Chu
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, China
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Wang XL, Gao XQ, Wang XC. Stochastic dynamics of actin filaments in guard cells regulating chloroplast localization during stomatal movement. PLANT, CELL & ENVIRONMENT 2011; 34:1248-57. [PMID: 21443604 DOI: 10.1111/j.1365-3040.2011.02325.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Actin filaments and chloroplasts in guard cells play roles in stomatal function. However, detailed actin dynamics vary, and the roles that they play in chloroplast localization during stomatal movement remain to be determined. We examined the dynamics of actin filaments and chloroplast localization in transgenic tobacco expressing green fluorescent protein (GFP)-mouse talin in guard cells by time-lapse imaging. Actin filaments showed sliding, bundling and branching dynamics in moving guard cells. During stomatal movement, long filaments can be severed into small fragments, which can form longer filaments by end-joining activities. With chloroplast movement, actin filaments near chloroplasts showed severing and elongation activity in guard cells during stomatal movement. Cytochalasin B treatment abolished elongation, bundling and branching activities of actin filaments in guard cells, and these changes of actin filaments, and as a result, more chloroplasts were localized at the centre of guard cells. However, chloroplast turning to avoid high light, and sliding of actin fragments near the chloroplast, was unaffected following cytochalasin B treatment in guard cells. We suggest that the sliding dynamics of actin may play roles in chloroplast turning in guard cells. Our results indicate that the stochastic dynamics of actin filaments in guard cells regulate chloroplast localization during stomatal movement.
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Affiliation(s)
- Xiu-Ling Wang
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
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