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Yan Y, Luo H, Qin Y, Yan T, Jia J, Hou Y, Liu Z, Zhai J, Long Y, Deng X, Cao X. Light controls mesophyll-specific post-transcriptional splicing of photoregulatory genes by AtPRMT5. Proc Natl Acad Sci U S A 2024; 121:e2317408121. [PMID: 38285953 PMCID: PMC10861865 DOI: 10.1073/pnas.2317408121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Accepted: 12/29/2023] [Indexed: 01/31/2024] Open
Abstract
Light plays a central role in plant growth and development, providing an energy source and governing various aspects of plant morphology. Previous study showed that many polyadenylated full-length RNA molecules within the nucleus contain unspliced introns (post-transcriptionally spliced introns, PTS introns), which may play a role in rapidly responding to changes in environmental signals. However, the mechanism underlying post-transcriptional regulation during initial light exposure of young, etiolated seedlings remains elusive. In this study, we used FLEP-seq2, a Nanopore-based sequencing technique, to analyze nuclear RNAs in Arabidopsis (Arabidopsis thaliana) seedlings under different light conditions and found numerous light-responsive PTS introns. We also used single-nucleus RNA sequencing (snRNA-seq) to profile transcripts in single nucleus and investigate the distribution of light-responsive PTS introns across distinct cell types. We established that light-induced PTS introns are predominant in mesophyll cells during seedling de-etiolation following exposure of etiolated seedlings to light. We further demonstrated the involvement of the splicing-related factor A. thaliana PROTEIN ARGININE METHYLTRANSFERASE 5 (AtPRMT5), working in concert with the E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), a critical repressor of light signaling pathways. We showed that these two proteins orchestrate light-induced PTS events in mesophyll cells and facilitate chloroplast development, photosynthesis, and morphogenesis in response to ever-changing light conditions. These findings provide crucial insights into the intricate mechanisms underlying plant acclimation to light at the cell-type level.
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Affiliation(s)
- Yan Yan
- Key Laboratory of Seed Innovation, State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing100101, China
| | - Haofei Luo
- Key Laboratory of Seed Innovation, State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing100101, China
| | - Yuwei Qin
- Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen518055, China
| | - Tingting Yan
- Key Laboratory of Tropical Fruit Tree Biology of Hainan Province, Institute of Tropical Fruit Trees, Hainan Academy of Agricultural Sciences, Haikou571100, China
| | - Jinbu Jia
- Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen518055, China
| | - Yifeng Hou
- Key Laboratory of Seed Innovation, State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing100101, China
| | - Zhijian Liu
- Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen518055, China
| | - Jixian Zhai
- Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen518055, China
| | - Yanping Long
- Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen518055, China
| | - Xian Deng
- Key Laboratory of Seed Innovation, State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing100101, China
| | - Xiaofeng Cao
- Key Laboratory of Seed Innovation, State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing100101, China
- University of Chinese Academy of Sciences, Beijing100049, China
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Ouk R, Oi T, Sugiura D, Taniguchi M. Structural changes of mesophyll cells in the rice leaf tissue in response to salinity stress based on the three-dimensional analysis. AoB Plants 2024; 16:plae016. [PMID: 38690081 PMCID: PMC11059269 DOI: 10.1093/aobpla/plae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 04/18/2024] [Indexed: 05/02/2024]
Abstract
Rice leaf blades have intricate-shaped mesophyll cells (MCs) with a large volume of chloroplasts enhancing gas exchange between stroma and intercellular airspace (IAS). Since the rice MCs do not form palisade or spongy tissue cells and are considered monotypic cells, the structural analysis of MCs in the middle part of the leaf tissue has been done, neglecting the various shapes of MCs can be observed on the cross-section of rice leaves. Moreover, the middle MC layer is sandwiched between the upper and lower layers and is more restricted in its demand for light and CO2 entering from the outside. Therefore, the different layers of MCs may differ in their sensitivity to salt stress that causes structural changes in cells. This study aims to elucidate the intra- and extra-cellular structures of MC in different layers of leaf tissue and determine how salinity affects the MC structure in each layer. The mesophyll tissue was divided into adaxial, middle and abaxial layers, and eight MCs and chloroplast regions were selected from each layer and reconstructed into three-dimensional (3D) representations. The whole leaf anatomical and physiological parameters were measured to find the effects of salinity stress on the MC structures. As a result, the 3D analysis of rice leaf tissue revealed the different structures of MCs with greater diversity in the adaxial and abaxial layers than in the middle layer. Salinity stress reduced the size and height of the MCs and coverage of the chloroplast on the cytoplasm periphery of the adaxial and abaxial layers, as well as the chloroplast size of adaxial MCs. Overall, these results reveal the variation of rice MC in leaf tissue and suggest the higher sensitivity to salt stress in the adaxial mesophyll among the layers, which may partly account for the decrease in photosynthetic capacity.
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Affiliation(s)
- Rachana Ouk
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Takao Oi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Daisuke Sugiura
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Mitsutaka Taniguchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
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Kato Y, Oi T, Taniguchi M. Aggregative movement of C 4 mesophyll chloroplasts is promoted by low CO 2 under high intensity blue light. Plant Biol (Stuttg) 2023; 25:563-570. [PMID: 36790102 DOI: 10.1111/plb.13512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 02/07/2023] [Indexed: 05/17/2023]
Abstract
C4 plants supply concentrated CO2 to bundle sheath (BS) cells, improving photosynthetic efficiency by suppressing photorespiration. Mesophyll chloroplasts in C4 plants are redistributed toward the sides of the BS cells (aggregative movement) in response to environmental stresses under light. Although this chloroplast movement is common in C4 plants, the significance and mechanisms underlying the aggregative movement remain unknown. Under environmental stresses, such as drought and salt, CO2 uptake from the atmosphere is suppressed by closing stomata to prevent water loss. We hypothesized that CO2 limitation may induce the chloroplast aggregative movement. In this study, the mesophyll chloroplast arrangement in a leaf of finger millet, an NAD-malic enzyme type C4 plant, was examined under different CO2 concentrations and light conditions. CO2 limitation around the leaves promoted the aggregative movement, but the aggregative movement was not suppressed, even at the higher CO2 concentration than in the atmosphere, under high intensity blue light. In addition, mesophyll chloroplasts did not change their arrangement under darkness or red light. From these results, it can be concluded that CO2 limitation is not a direct inducer of the aggregative movement but would be a promoting factor of the movement under high intensity blue light.
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Affiliation(s)
- Y Kato
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - T Oi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - M Taniguchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
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4
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Ouk R, Oi T, Sugiura D, Taniguchi M. 3-D reconstruction of rice leaf tissue for proper estimation of surface area of mesophyll cells and chloroplasts facing intercellular airspaces from 2-D section images. Ann Bot 2022; 130:991-998. [PMID: 36283030 PMCID: PMC9851327 DOI: 10.1093/aob/mcac133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND AND AIMS The surface area of mesophyll cells (Smes) and chloroplasts (Sc) facing the intercellular airspace (IAS) are important parameters for estimating photosynthetic activity from leaf anatomy. Although Smes and Sc are estimated based on the shape assumption of mesophyll cells (MCs), it is questionable if the assumption is correct for rice MCs with concave-convex surfaces. Therefore, in this study, we establish a reconstruction method for the 3-D representation of the IAS in rice leaf tissue to calculate the actual Smes and Sc with 3-D images and to determine the correct shape assumption for the estimation of Smes and Sc based on 2-D section images. METHODS We used serial section light microscopy to reconstruct 3-D representations of the IAS, MCs and chloroplasts in rice leaf tissue. Actual Smes and Sc values obtained from the 3-D representation were compared with those estimated from the 2-D images to find the correct shape-specific assumption (oblate or prolate spheroid) in different orientations (longitudinal and transverse sections) using the same leaf sample. KEY RESULTS The 3-D representation method revealed that volumes of the IAS and MCs accounted for 30 and 70 % of rice leaf tissue excluding epidermis, respectively, and the volume of chloroplasts accounted for 44 % of MCs. The shape-specific assumption on the sectioning orientation affected the estimation of Smes and Sc using 2-D section images with discrepancies of 10-38 %. CONCLUSIONS The 3-D representation of rice leaf tissue was successfully reconstructed using serial section light microscopy and suggested that estimation of Smes and Sc of the rice leaf is more accurate using longitudinal sections with MCs assumed as oblate spheroids than using transverse sections with MCs as prolate spheroids.
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Affiliation(s)
- Rachana Ouk
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Takao Oi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Daisuke Sugiura
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Mitsutaka Taniguchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
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Guo X, Liang J, Lin R, Zhang L, Zhang Z, Wu J, Wang X. Single-cell transcriptome reveals differentiation between adaxial and abaxial mesophyll cells in Brassica rapa. Plant Biotechnol J 2022; 20:2233-2235. [PMID: 36039389 PMCID: PMC9674316 DOI: 10.1111/pbi.13919] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/25/2022] [Accepted: 08/26/2022] [Indexed: 05/27/2023]
Affiliation(s)
- Xinlei Guo
- Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina
| | - Jianli Liang
- Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina
| | - Runmao Lin
- Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina
| | - Lupeng Zhang
- Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina
| | - Zhicheng Zhang
- Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina
| | - Jian Wu
- Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina
| | - Xiaowu Wang
- Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina
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Hu W, Lu Z, Meng F, Li X, Cong R, Ren T, Sharkey TD, Lu J. Erratum. New Phytol 2021; 231:2398. [PMID: 34390258 DOI: 10.1111/nph.17472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 05/13/2021] [Indexed: 06/13/2023]
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Liu Q, Li X, Fettke J. Starch Granules in Arabidopsis thaliana Mesophyll and Guard Cells Show Similar Morphology but Differences in Size and Number. Int J Mol Sci 2021; 22:5666. [PMID: 34073516 DOI: 10.3390/ijms22115666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/17/2021] [Accepted: 05/21/2021] [Indexed: 01/08/2023] Open
Abstract
Transitory starch granules result from complex carbon turnover and display specific situations during starch synthesis and degradation. The fundamental mechanisms that specify starch granule characteristics, such as granule size, morphology, and the number per chloroplast, are largely unknown. However, transitory starch is found in the various cells of the leaves of Arabidopsis thaliana, but comparative analyses are lacking. Here, we adopted a fast method of laser confocal scanning microscopy to analyze the starch granules in a series of Arabidopsis mutants with altered starch metabolism. This allowed us to separately analyze the starch particles in the mesophyll and in guard cells. In all mutants, the guard cells were always found to contain more but smaller plastidial starch granules than mesophyll cells. The morphological properties of the starch granules, however, were indiscernible or identical in both types of leaf cells.
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Hu W, Lu Z, Meng F, Li X, Cong R, Ren T, Sharkey TD, Lu J. The reduction in leaf area precedes that in photosynthesis under potassium deficiency: the importance of leaf anatomy. New Phytol 2020; 227:1749-1763. [PMID: 32367581 DOI: 10.1111/nph.16644] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 04/26/2020] [Indexed: 06/11/2023]
Abstract
Synergistic improvement in leaf photosynthetic area and rate is essential for enhancing crop yield. However, reduction in leaf area occurs earlier than that in the photosynthetic rate under potassium (K) deficiency stress. The photosynthetic capacity and anatomical characteristics of oilseed rape (Brassica napus) leaves in different growth stages under different K levels were observed to clarify the mechanism regulating this process. Increased mesophyll cell size and palisade tissue thickness, in K-deficient leaves triggered significant enlargement of mesophyll cell area per transverse section width (S/W), in turn inhibiting leaf expansion. However, there was only a minor difference in chloroplast morphology, likely because of K redistribution from vacuole to chloroplast. As K stress increased, decreased mesophyll surface exposed to intercellular space and chloroplast density induced longer distances between neighbouring chloroplasts (Dchl-chl ) and decreased the chloroplast surface area exposed to intercellular space (Sc /S); conversely this induced a greater limitation imposed by the cytosol on CO2 transport, further reducing the photosynthetic rate. Changes in S/W associated with mesophyll cell morphology occurred earlier than changes in Sc /S and Dchl-chl , inducing a decrease in leaf area before photosynthetic rate reduction. Adequate K nutrition simultaneously increases photosynthetic area and rate, thus enhancing crop yield.
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Affiliation(s)
- Wenshi Hu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
| | - Zhifeng Lu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
| | - Fanjin Meng
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
| | - Xiaokun Li
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
| | - Rihuan Cong
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
| | - Tao Ren
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
| | - Thomas D Sharkey
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
| | - Jianwei Lu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
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Oi T, Enomoto S, Nakao T, Arai S, Yamane K, Taniguchi M. Three-dimensional ultrastructural change of chloroplasts in rice mesophyll cells responding to salt stress. Ann Bot 2020; 125:833-840. [PMID: 31773147 PMCID: PMC7182591 DOI: 10.1093/aob/mcz192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/26/2019] [Indexed: 05/02/2023]
Abstract
BACKGROUND AND AIMS Excess salinity inhibits the metabolism of various systems and induces structural changes, especially in chloroplasts. Although the chloroplast body seems to swell under salinity stress as observed by conventional transmission electron microscopy, previous studies are limited to 2-D data and lack quantitative comparisons because specimens need to be sliced into ultrathin sections. This study shows three-dimensionally the structural changes in a whole mesophyll cell responding to salinity stress by serial sectioning with a focused ion beam scanning electron microscope (FIB-SEM) and compares the differences in chloroplast structures based on reconstructed models possessing accurate numerical voxel values. METHODS Leaf blades of rice plants treated with 100 mm NaCl or without (control) for 4 d were fixed chemically and embedded in resin. The specimen blocks were sectioned and observed using the FIB-SEM, and then the sliced image stacks were reconstructed into 3-D models by image processing software. KEY RESULTS On the transverse sections of rice mesophyll cells, the chloroplasts in the control leaves appeared to be elongated meniscus lens shaped, while those in the salt-treated leaves appear to be expanded oval shaped. The 3-D models based on serial sectioning images showed that the chloroplasts in the control cells spread like sheets fitted to the shape of the cell wall and in close contact with the adjacent chloroplasts. In contrast, those in the salt-stressed cells curled up into a ball and fitted to cell protuberances without being in close contact with adjacent chloroplasts. Although the shapes of chloroplasts were clearly different between the two treatments, their volumes did not differ. CONCLUSIONS The 3-D reconstructed models of whole rice mesophyll cells indicated that chloroplasts under salt stress conditions were not swollen but became spherical without increasing their volume. This is in contrast to findings of previous studies based on 2-D images.
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Affiliation(s)
- Takao Oi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Sakiko Enomoto
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Tomoyo Nakao
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Shigeo Arai
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Koji Yamane
- Graduate School of Agriculture, Kindai University, Nara, Japan
| | - Mitsutaka Taniguchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
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Abstract
This article comments on: Turner GW, Parrish AN, Zager JJ, Fischedick JT, Lange BM. 2018. Assessment of flux through oleoresin biosynthesis in epithelial cells of loblolly pine resin ducts. Journal of Experimental Botany 70, 217–230.
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Affiliation(s)
- Harro Bouwmeester
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, the Netherlands
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Gao Y, Zhang C, Han X, Wang ZY, Ma L, Yuan DP, Wu JN, Zhu XF, Liu JM, Li DP, Hu YB, Xuan YH. Inhibition of OsSWEET11 function in mesophyll cells improves resistance of rice to sheath blight disease. Mol Plant Pathol 2018; 19:2149-2161. [PMID: 29660235 PMCID: PMC6638089 DOI: 10.1111/mpp.12689] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 04/04/2018] [Accepted: 04/08/2018] [Indexed: 05/20/2023]
Abstract
Pathogen-host interaction is a complicated process; pathogens mainly infect host plants to acquire nutrients, especially sugars. Rhizoctonia solani, the causative agent of sheath blight disease, is a major pathogen of rice. However, it is not known how this pathogen obtains sugar from rice plants. In this study, we found that the rice sugar transporter OsSWEET11 is involved in the pathogenesis of sheath blight disease. Quantitative real-time polymerase chain reaction (qRT-PCR) and β-d-glucuronidase expression analyses showed that R. solani infection significantly enhanced OsSWEET11 expression in leaves amongst the clade III SWEET members. The analyses of transgenic plants revealed that Ossweet11 mutants were less susceptible, whereas plants overexpressing OsSWEET11 were more susceptible, to sheath blight compared with wild-type controls, but the yield of OsSWEET11 mutants and overexpressors was reduced. SWEETs become active on oligomerization. Split-ubiquitin yeast two-hybrid, bimolecular fluorescence complementation and co-immunoprecipitation assays showed that mutated OsSWEET11 interacted with normal OsSWEET11. In addition, expression of conserved residue mutated AtSWEET1 inhibited normal AtSWEET1 activity. To analyse whether inhibition of OsSWEET11 function in mesophyll cells is related to defence against this disease, mutated OsSWEET11 was expressed under the control of the Rubisco promoter, which is specific for green tissues. The resistance of transgenic plants to sheath blight disease, but not other disease, was improved, whereas yield production was not obviously affected. Overall, these results suggest that R. solani might acquire sugar from rice leaves by the activation of OsSWEET11 expression. The plants can be protected from infection by manipulation of the expression of OsSWEET11 without affecting the crop yield.
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Affiliation(s)
- Yue Gao
- College of Plant ProtectionShenyang Agricultural UniversityShenyang 110866China
| | - Chong Zhang
- College of Plant ProtectionShenyang Agricultural UniversityShenyang 110866China
| | - Xiao Han
- College of Biological Science and EngineeringFuzhou UniversityFuzhou 350108China
- Biotechnology Research InstituteChinese Academy of Agricultural SciencesBeijing 100081China
| | - Zi Yuan Wang
- College of Plant ProtectionShenyang Agricultural UniversityShenyang 110866China
| | - Lai Ma
- College of Resources & Environmental SciencesNanjing Agricultural UniversityNanjing 210095China
| | - De Peng Yuan
- College of Plant ProtectionShenyang Agricultural UniversityShenyang 110866China
| | - Jing Ni Wu
- Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of SciencesShanghai 200032China
| | - Xiao Feng Zhu
- College of Plant ProtectionShenyang Agricultural UniversityShenyang 110866China
| | - Jing Miao Liu
- Department of Agricultural and Biological TechnologyWenzhou Agricultural Science Research Institute (Wenzhou Vocational College of Science & Technology)Wenzhou 325006China
| | - Dao Pin Li
- Department of Agricultural and Biological TechnologyWenzhou Agricultural Science Research Institute (Wenzhou Vocational College of Science & Technology)Wenzhou 325006China
| | - Yi Bing Hu
- College of Resources & Environmental SciencesNanjing Agricultural UniversityNanjing 210095China
| | - Yuan Hu Xuan
- College of Plant ProtectionShenyang Agricultural UniversityShenyang 110866China
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12
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Smillie IRA, Pyke KA, Murchie EH. Variation in vein density and mesophyll cell architecture in a rice deletion mutant population. J Exp Bot 2012; 63:4563-70. [PMID: 22685308 PMCID: PMC3421994 DOI: 10.1093/jxb/ers142] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 04/15/2012] [Accepted: 02/08/2012] [Indexed: 05/18/2023]
Abstract
There is a need to develop rice plants with improved photosynthetic capacity and efficiency in order to enhance potential grain yield. Alterations in internal leaf morphology may be needed to underpin some of these improvements. One target is the production of a 'Kranz-like' anatomy, commonly considered to be required to achieve the desired levels of photosynthesis seen in C(4) crops. Kranz anatomy typically has two or three mesophyll cells interspersing adjacent veins. As a first step to determining the potential for such anatomical modifications in rice leaves, a population of rice deletion mutants was analysed for alterations in vein patterning and mesophyll cells in the interveinal regions. Significant variation is demonstrated in vein arrangement and the sequential distribution of major and minor veins across the leaf width, although there is a significant correlation between the total number of veins present and the width of the leaf. Thus the potential is demonstrated for modifying rice leaf structure. Six distinct rice mutant lines, termed altered leaf morphology (alm) mutants, were analysed for the architecture of their interveinal mesophyll cell arrangement. It is shown that in these mutant lines, the distance between adjacent minor veins and adjacent minor and major veins is essentially determined by the size of the interveinal mesophyll cells rather than changes in mesophyll cell number across this region, and hence interveinal distance changes as a result of cell expansion rather than cell division. This observation will be important when developing screens for traits relevant for the introduction of Kranz anatomy into rice.
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Affiliation(s)
- I R A Smillie
- Plant and Crop Sciences Division, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK
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Maai E, Miyake H, Taniguchi M. Differential positioning of chloroplasts in C4 mesophyll and bundle sheath cells. Plant Signal Behav 2011; 6:1111-3. [PMID: 21757999 PMCID: PMC3260704 DOI: 10.4161/psb.6.8.15809] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 04/12/2011] [Indexed: 05/06/2023]
Abstract
Chloroplast photorelocation movement is extensively studied in C3 but not C4 plants. C4 plants have 2 types of photosynthetic cells: mesophyll and bundle sheath cells. Mesophyll chloroplasts are randomly distributed along cell walls, whereas bundle sheath chloroplasts are located close to the vascular tissues or mesophyll cells depending on the plant species. The cell-specific C 4 chloroplast arrangement is established during cell maturation, and is maintained throughout the life of the cell. However, only mesophyll chloroplasts can change their positions in response to environmental stresses. The migration pattern is unique to C4 plants and differs from that of C3 chloroplasts. In this mini-review, we highlight the cell-specific disposition of chloroplasts in C4 plants and discuss the possible physiological significances.
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Affiliation(s)
- Eri Maai
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, Japan
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Islam MS, Takagi S. Co-localization of mitochondria with chloroplasts is a light-dependent reversible response. Plant Signal Behav 2010; 5:146-7. [PMID: 20023395 PMCID: PMC2884119 DOI: 10.4161/psb.5.2.10410] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 10/22/2009] [Accepted: 10/23/2009] [Indexed: 05/28/2023]
Abstract
Co-localization of mitochondria with chloroplasts in plant cells has long been noticed as beneficial interactions of the organelles to active photosynthesis. Recently, we have found that mitochondria in mesophyll cells of Arabidopsis thaliana expressing mitochondrion-targeted green fluorescent protein (GFP) change their distribution in a light-dependent manner. Mitochondria occupy the periclinal and anticlinal regions of palisade cells under weak and strong blue light, respectively. Redistributed mitochondria seem to be rendered static through co-localization with chloroplasts. Here we further demonstrated that distribution patterns of mitochondria, together with chloroplasts, returned back to those of dark-adapted state during dark incubation after blue-light illumination. Reversible association of the two organelles may underlie flexible adaptation of plants to environmental fluctuations.
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Affiliation(s)
- Md Sayeedul Islam
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan.
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