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Zhang H, Xie Z, Tu X, Liu A, Chen J, He Y, Wu B, Zhou Z. Morphological and proteomic study of waterlogging tolerance in cotton. Sci Rep 2024; 14:14550. [PMID: 38914604 PMCID: PMC11196664 DOI: 10.1038/s41598-024-64322-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 06/07/2024] [Indexed: 06/26/2024] Open
Abstract
Floating seedling cultivation technique is a novel seedling method in cotton and it provides an ideal model to study cotton growing under waterlogging stress. Morphological character and proteomic profile of the primary root from the seedling cultured by the new technology were evaluated in this study. Compared to seedlings cultured by the traditional method, the diameter of the taproot from floating technology is small at all five seedling stages from one-leaf stage to five-leaf stage. There are similar changes between the thickness of cortex and diameter of stele, which increased from the one- to the two-leaf stage but decreased from the two- to the five-leaf stage. At the one-leaf stage, the number and volume of mitochondria in the primary root-tip cells were less than those in the control. At the two-leaf stage, there was significantly less electron-dense material in the primary root-tip cells than those in the control group. From the one- to the two-leaf stage, the vacuole volume was significantly smaller than that in the control. Total 28 differentially expressed proteins were revealed from aquatic and control group roots of cotton seedlings at the three-leaf stage by two-dimensional electrophoresis, which included 24 up-regulated and four down-regulated proteins. The relative expression of the phosphoglycerate kinase (PGK) gene in aquatic roots increased from the one- to the four-leaf stage but declined rapidly from the four- to the five-leaf stage. The relative expression of the 14-3-3b gene tended to decrease from the one- to the five-leaf stage. The PGK and 14-3-3b genes were specifically expressed in the aquatic roots at the three-leaf stage. In brief, these changes induced waterlogging resistance in the aquatic roots of cotton seedlings in the floating nursery, thereby causing the roots to adapt to the aquatic environment, promoting the growth and development of cotton seedlings.
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Affiliation(s)
- Hao Zhang
- Cotton Research Institute, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
- Key Laboratory of Ministry of Education for Crop Physiology and Molecular Biology, Changsha, 410128, China
| | - Zhangshu Xie
- Cotton Research Institute, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
- Key Laboratory of Ministry of Education for Crop Physiology and Molecular Biology, Changsha, 410128, China
| | - Xiaoju Tu
- Cotton Research Institute, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
- Key Laboratory of Ministry of Education for Crop Physiology and Molecular Biology, Changsha, 410128, China
| | - Aiyu Liu
- Cotton Research Institute, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
- Key Laboratory of Ministry of Education for Crop Physiology and Molecular Biology, Changsha, 410128, China
| | - Jinxiang Chen
- Cotton Research Institute, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
- Key Laboratory of Ministry of Education for Crop Physiology and Molecular Biology, Changsha, 410128, China
| | - Yunxin He
- Hunan Institute of Cotton Science, Changde, 415101, China
| | - Bibo Wu
- Hunan Biological and Electromechanical Polytechmic, Changsha, 410127, China.
| | - Zhonghua Zhou
- Cotton Research Institute, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China.
- Key Laboratory of Ministry of Education for Crop Physiology and Molecular Biology, Changsha, 410128, China.
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Hoermayer L, Montesinos JC, Trozzi N, Spona L, Yoshida S, Marhava P, Caballero-Mancebo S, Benková E, Heisenberg CP, Dagdas Y, Majda M, Friml J. Mechanical forces in plant tissue matrix orient cell divisions via microtubule stabilization. Dev Cell 2024; 59:1333-1344.e4. [PMID: 38579717 DOI: 10.1016/j.devcel.2024.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 11/13/2023] [Accepted: 03/08/2024] [Indexed: 04/07/2024]
Abstract
Plant morphogenesis relies exclusively on oriented cell expansion and division. Nonetheless, the mechanism(s) determining division plane orientation remain elusive. Here, we studied tissue healing after laser-assisted wounding in roots of Arabidopsis thaliana and uncovered how mechanical forces stabilize and reorient the microtubule cytoskeleton for the orientation of cell division. We identified that root tissue functions as an interconnected cell matrix, with a radial gradient of tissue extendibility causing predictable tissue deformation after wounding. This deformation causes instant redirection of expansion in the surrounding cells and reorientation of microtubule arrays, ultimately predicting cell division orientation. Microtubules are destabilized under low tension, whereas stretching of cells, either through wounding or external aspiration, immediately induces their polymerization. The higher microtubule abundance in the stretched cell parts leads to the reorientation of microtubule arrays and, ultimately, informs cell division planes. This provides a long-sought mechanism for flexible re-arrangement of cell divisions by mechanical forces for tissue reconstruction and plant architecture.
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Affiliation(s)
- Lukas Hoermayer
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria; Department of Plant Molecular Biology (DMBV), University of Lausanne, 1015 Lausanne, Switzerland; Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter, Vienna, Austria
| | - Juan Carlos Montesinos
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria; Instituto Universitario de Biotecnología y Biomedicina (BIOTECMED), Departamento de Bioquímica y Biología Molecular, Universitat de València, 46100 Burjassot, Spain
| | - Nicola Trozzi
- Department of Plant Molecular Biology (DMBV), University of Lausanne, 1015 Lausanne, Switzerland
| | - Leonhard Spona
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | - Saiko Yoshida
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria; Max Planck Institute for Plant Breeding Research, 50829 Carl-von-Linné-Weg 10, Cologne, Germany
| | - Petra Marhava
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria; Umeå Plant Science Centre (UPSC), Department of Forest Genetics and Plant Physiology, University of Agricultural Sciences (SLU), 90183 Umeå, Sweden
| | | | - Eva Benková
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | | | - Yasin Dagdas
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter, Vienna, Austria
| | - Mateusz Majda
- Department of Plant Molecular Biology (DMBV), University of Lausanne, 1015 Lausanne, Switzerland
| | - Jiří Friml
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria.
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3
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Feng X, Pan S, Tu H, Huang J, Xiao C, Shen X, You L, Zhao X, Chen Y, Xu D, Qu X, Hu H. IQ67 DOMAIN protein 21 is critical for indentation formation in pavement cell morphogenesis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023; 65:721-738. [PMID: 36263896 DOI: 10.1111/jipb.13393] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 10/15/2022] [Indexed: 05/26/2023]
Abstract
In plants, cortical microtubules anchor to the plasma membrane in arrays and play important roles in cell shape. However, the molecular mechanism of microtubule binding proteins, which connect the plasma membrane and cortical microtubules in cell morphology remains largely unknown. Here, we report that a plasma membrane and microtubule dual-localized IQ67 domain protein, IQD21, is critical for cotyledon pavement cell (PC) morphogenesis in Arabidopsis. iqd21 mutation caused increased indentation width, decreased lobe length, and similar lobe number of PCs, whereas IQD21 overexpression had a different effect on cotyledon PC shape. Weak overexpression led to increased lobe number, decreased indentation width, and similar lobe length, while moderate or great overexpression resulted in decreased lobe number, indentation width, and lobe length of PCs. Live-cell observations revealed that IQD21 accumulation at indentation regions correlates with lobe initiation and outgrowth during PC development. Cell biological and genetic approaches revealed that IQD21 promotes transfacial microtubules anchoring to the plasma membrane via its polybasic sites and bundling at the indentation regions in both periclinal and anticlinal walls. IQD21 controls cortical microtubule organization mainly through promoting Katanin 1-mediated microtubule severing during PC interdigitation. These findings provide the genetic evidence that transfacial microtubule arrays play a determinant role in lobe formation, and the insight into the molecular mechanism of IQD21 in transfacial microtubule organization at indentations and puzzle-shaped PC development.
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Affiliation(s)
- Xinhua Feng
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shujuan Pan
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Haifu Tu
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Junjie Huang
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, 430070, China
| | - Chuanlei Xiao
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xin Shen
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Lei You
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xinyan Zhao
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - Yongqiang Chen
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Danyun Xu
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xiaolu Qu
- Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
| | - Honghong Hu
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
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Brueggeman JM, Windham IA, Nebenführ A. Nuclear movement in growing Arabidopsis root hairs involves both actin filaments and microtubules. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:5388-5399. [PMID: 35554524 DOI: 10.1093/jxb/erac207] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Nuclear migration during growth and development is a conserved phenomenon among many eukaryotic species. In Arabidopsis, movement of the nucleus is important for root hair growth, but the detailed mechanism behind this movement is not well known. Previous studies in different cell types have reported that the myosin XI-I motor protein is responsible for this nuclear movement by attaching to the nuclear transmembrane protein complex WIT1/WIT2. Here, we analyzed nuclear movement in growing root hairs of wild-type, myosin xi-i, and wit1 wit2 Arabidopsis lines in the presence of actin and microtubule-disrupting inhibitors to determine the individual effects of actin filaments and microtubules on nuclear movement. We discovered that forward nuclear movement during root hair growth can occur in the absence of myosin XI-I, suggesting the presence of an alternative actin-based mechanism that mediates rapid nuclear displacements. By quantifying nuclear movements with high temporal resolution during the initial phase of inhibitor treatment, we determined that microtubules work to dampen erratic nuclear movements during root hair growth. We also observed microtubule-dependent backwards nuclear movement when actin filaments were impaired in the absence of myosin XI-I, indicating the presence of complex interactions between the cytoskeletal arrays during nuclear movements in growing root hairs.
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Affiliation(s)
- Justin M Brueggeman
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
| | - Ian A Windham
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, USA
| | - Andreas Nebenführ
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
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5
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Tang W, Lin W, Zhou X, Guo J, Dang X, Li B, Lin D, Yang Z. Mechano-transduction via the pectin-FERONIA complex activates ROP6 GTPase signaling in Arabidopsis pavement cell morphogenesis. Curr Biol 2021; 32:508-517.e3. [PMID: 34875231 DOI: 10.1016/j.cub.2021.11.031] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 09/28/2021] [Accepted: 11/11/2021] [Indexed: 01/02/2023]
Abstract
During growth and morphogenesis, plant cells respond to mechanical stresses resulting from spatiotemporal changes in the cell wall that bear high internal turgor pressure. Microtubule (MT) arrays are reorganized to align in the direction of maximal tensile stress, presumably reinforcing the local cell wall by guiding the synthesis of cellulose. However, how mechanical forces regulate MT reorganization remains largely unknown. Here, we demonstrate that mechanical signaling that is based on the Catharanthus roseus RLK1-like kinase (CrRLK1L) subfamily receptor kinase FERONIA (FER) regulates the reorganization of cortical MT in cotyledon epidermal pavement cells (PCs) in Arabidopsis. Recessive mutations in FER compromised MT responses to mechanical perturbations, such as single-cell ablation, compression, and isoxaben treatment, in these PCs. These perturbations promoted the activation of ROP6 guanosine triphosphatase (GTPase) that acts directly downstream of FER. Furthermore, defects in the ROP6 signaling pathway negated the reorganization of cortical MTs induced by these stresses. Finally, reduction in highly demethylesterified pectin, which binds the extracellular malectin domains of FER and is required for FER-mediated ROP6 activation, also impacted mechanical induction of cortical MT reorganization. Taken together, our results suggest that the FER-pectin complex senses and/or transduces mechanical forces to regulate MT organization through activating the ROP6 signaling pathway in Arabidopsis.
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Affiliation(s)
- Wenxin Tang
- FAFU-UCR Joint Center for Horticultural Biology and Metabolomics Center, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China; Institute of Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521, USA
| | - Wenwei Lin
- FAFU-UCR Joint Center for Horticultural Biology and Metabolomics Center, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China; Institute of Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521, USA
| | - Xiang Zhou
- FAFU-UCR Joint Center for Horticultural Biology and Metabolomics Center, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China; Institute of Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521, USA
| | - Jingzhe Guo
- Institute of Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521, USA
| | - Xie Dang
- Basic Forestry and Proteomic Research Center, Fujian Provincial Key Laboratory of Plant Functional Biology, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Binqi Li
- FAFU-UCR Joint Center for Horticultural Biology and Metabolomics Center, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Deshu Lin
- Basic Forestry and Proteomic Research Center, Fujian Provincial Key Laboratory of Plant Functional Biology, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Zhenbiao Yang
- FAFU-UCR Joint Center for Horticultural Biology and Metabolomics Center, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China; Institute of Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521, USA.
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6
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Satoh S. Promotion of auxin- and gibberellin-induced elongation of epicotyl segments of Vigna angularis by short-chain carboxylic acids. JOURNAL OF PLANT RESEARCH 2021; 134:355-363. [PMID: 33559785 DOI: 10.1007/s10265-021-01261-z] [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: 10/14/2020] [Accepted: 01/29/2021] [Indexed: 06/12/2023]
Abstract
Pollen tube growth is inhibited and promoted by long- and short-chain carboxylic acids, respectively, but is not affected by formic acid. For auxin- and gibberellin-induced elongation of in vitro cultured epicotyl segments of adzuki bean (Vigna angularis), a series of carboxylic acids showed similar effects as that on pollen tube growth except that formic acid showed the strongest promotive effect. The effects of formic acid and GA3 on IAA-induced elongation were additive and both were strongly inhibited by inhibitors of cellulose synthesis (coumarin) and microtubule formation (colchicine). Formic acid, possibly by incorporation into the segments, prolonged the promotion by IAA and GA3 of the elongation of epicotyl segments. Based on these results and later advances in our understanding of metabolism and the role of formic acid in protecting against oxidative stress, a possible role of formic acid on stem elongation is discussed.
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Affiliation(s)
- Shinobu Satoh
- Institute of Biological Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
- Biological Institute, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0027, Japan.
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Filipin EP, Pereira DT, Ouriques LC, Bouzon ZL, Simioni C. Participation of actin filaments, myosin and phosphatidylinositol 3-kinase in the formation and polarisation of tetraspore germ tube of Gelidium floridanum (Rhodophyta, Florideophyceae). PLANT BIOLOGY (STUTTGART, GERMANY) 2019; 21:352-360. [PMID: 30472775 DOI: 10.1111/plb.12946] [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: 10/03/2018] [Accepted: 11/21/2018] [Indexed: 06/09/2023]
Abstract
This study aimed to examine the evidence of direct interaction among actin, myosin and phosphatidylinositol 3-kinase (PI3K) in the polarisation and formation of the tetraspore germ tube of Gelidium floridanum. After release, tetraspores were exposed to cytochalasin B, latrunculin B, LY294002 and BDM for a period of 6 h. In control samples, formation of the germ tube occurred after the experimental period, with cellulose formation and elongated chloroplasts moving through the tube region in the presence of F-actin. In the presence of cytochalasin B, an inhibitor of F-actin, latrunculin B, an inhibitor of G-actin, and BDM, a myosin inhibitor, tetraspores showed no formation of the germ tube or cellulose. Spherical-shaped chloroplasts were observed in the central region with a few F-actin filaments in the periphery of the cytoplasm. Tetraspores treated with LY294002, a PI3K inhibitor, showed no formation of the tube at the highest concentrations. Polarisation of cytoplasmic contents did not occur, only cellulose formation. It was concluded that F-actin directs the cell wall components and contributes to the maintenance of chloroplast shape and elongation during germ tube formation. PI3K plays a fundamental role in signalling for the asymmetric polarisation of F-actin. Thus, F-actin regulates the polarisation and germination processes of tetraspores of G. floridanum.
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Affiliation(s)
- E P Filipin
- Plant Cell Biology Laboratory, Department of Cell Biology, Embryology and Genetics, Federal University of Santa Catarina, Florianópolis, SC, Brazil
| | - D T Pereira
- Plant Cell Biology Laboratory, Department of Cell Biology, Embryology and Genetics, Federal University of Santa Catarina, Florianópolis, SC, Brazil
| | - L C Ouriques
- Central Laboratory of Electron Microscopy, Federal University of Santa Catarina, Florianópolis, SC, Brazil
| | - Z L Bouzon
- Central Laboratory of Electron Microscopy, Federal University of Santa Catarina, Florianópolis, SC, Brazil
| | - C Simioni
- Postdoctoral Research of Postgraduate Program in Cell Biology and Development, Department of Cell Biology, Embryology and Genetics, Federal University of Santa Catarina, Florianópolis, SC, Brazil
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Bogaert KA, Beeckman T, De Clerck O. Egg activation-triggered shape change in the Dictyota dichotoma (Phaeophyceae) zygote is actin-myosin and secretion dependent. ANNALS OF BOTANY 2017; 120:529-538. [PMID: 28961769 PMCID: PMC5737549 DOI: 10.1093/aob/mcx085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 06/07/2017] [Indexed: 06/07/2023]
Abstract
Background and Aims Cellular morphogenesis in land plants and brown algae is typically a slow process involving growth established by an interplay of turgor pressure and cell wall rigidity. However, a recent study showed that zygotes of the brown alga Dictyota dichotoma undergo a rapid shape change from a sphere to an elongated spheroid in about 90 s, establishing the first body axis. Methods Using a combination of pharmacology, staining techniques, membrane depolarization and microscopy techniques (brightfield, transmission electron microscopy and confocal laser scanning microscopy), egg activation and the shape change of the egg cell of D. dichotoma was studied. Key Results It was established that elongation of the zygote does not involve growth, i.e. a positive change in size. The elongation is dependent on F-actin and myosin but independent of microtubules. Secretion was also found to be necessary for elongation after addition of brefeldin A. Moreover, a temporal correlation between extracellular matrix secretion and elongation was observed. Ionomycin and high potassium seawater are capable of triggering the onset of elongation, suggesting a role for membrane depolarization and calcium influx in the signalling mechanism. The elongated cells are shorter in the presence of ionomycin, suggesting a role for calcium in elongation. Conclusions A model is proposed in which the fast elongation of the fertilized egg in Dictyota is accomplished by a force generated by F-actin and myosin, regulated by cytoplasmic calcium concentrations and by secretion during elongation lowering the antagonistic force. The finding of early extracellular matrix secretion, membrane depolarization and ionophore-triggered egg activation suggest significant differences in the mechanism of egg activation signalling between D. dichotoma and the oogamous brown algal model system Fucus .
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Affiliation(s)
- Kenny A Bogaert
- Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium
| | - Tom Beeckman
- VIB-UGent Center for Plant Systems Biology, Technologiepark 927, B-9052 Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Ghent, Belgium
| | - Olivier De Clerck
- Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium
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Kimata Y, Higaki T, Kawashima T, Kurihara D, Sato Y, Yamada T, Hasezawa S, Berger F, Higashiyama T, Ueda M. Cytoskeleton dynamics control the first asymmetric cell division in Arabidopsis zygote. Proc Natl Acad Sci U S A 2016; 113:14157-14162. [PMID: 27911812 PMCID: PMC5150365 DOI: 10.1073/pnas.1613979113] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The asymmetric cell division of the zygote is the initial and crucial developmental step in most multicellular organisms. In flowering plants, whether zygote polarity is inherited from the preexisting organization in the egg cell or reestablished after fertilization has remained elusive. How dynamically the intracellular organization is generated during zygote polarization is also unknown. Here, we used a live-cell imaging system with Arabidopsis zygotes to visualize the dynamics of the major elements of the cytoskeleton, microtubules (MTs), and actin filaments (F-actins), during the entire process of zygote polarization. By combining image analysis and pharmacological experiments using specific inhibitors of the cytoskeleton, we found features related to zygote polarization. The preexisting alignment of MTs and F-actin in the egg cell is lost on fertilization. Then, MTs organize into a transverse ring defining the zygote subapical region and driving cell outgrowth in the apical direction. F-actin forms an apical cap and longitudinal arrays and is required to position the nucleus to the apical region of the zygote, setting the plane of the first asymmetrical division. Our findings show that, in flowering plants, the preexisting cytoskeletal patterns in the egg cell are lost on fertilization and that the zygote reorients the cytoskeletons to perform directional cell elongation and polar nuclear migration.
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Affiliation(s)
- Yusuke Kimata
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Takumi Higaki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8562, Japan
| | - Tomokazu Kawashima
- Gregor Mendel Institute, Vienna Biocenter, Austrian Academy of Sciences, 1030 Vienna, Austria
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546
| | - Daisuke Kurihara
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
- Japan Science and Technology Agency, Exploratory Research for Advanced Technology Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Yoshikatsu Sato
- Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Tomomi Yamada
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
- Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Seiichiro Hasezawa
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8562, Japan
| | - Frederic Berger
- Gregor Mendel Institute, Vienna Biocenter, Austrian Academy of Sciences, 1030 Vienna, Austria
| | - Tetsuya Higashiyama
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
- Japan Science and Technology Agency, Exploratory Research for Advanced Technology Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
- Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Minako Ueda
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan;
- Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
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Meng X, Zhao Q, Jin Y, Yu J, Yin Z, Chen S, Dai S. Chilling-responsive mechanisms in halophyte Puccinellia tenuiflora seedlings revealed from proteomics analysis. J Proteomics 2016; 143:365-381. [PMID: 27130536 DOI: 10.1016/j.jprot.2016.04.038] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/14/2016] [Accepted: 04/24/2016] [Indexed: 11/28/2022]
Abstract
Alkali grass (Puccinellia tenuiflora), a monocotyledonous perennial halophyte species, is a good pasture with great nutritional value for livestocks. It can thrive under low temperature in the saline-alkali soil of Songnen plain in northeastern China. In the present study, the chilling-responsive mechanism in P. tenuiflora leaves was investigated using physiological and proteomic approaches. After treatment of 10°C for 10 and 20days, photosynthesis, biomass, contents of osmolytes and antioxidants, and activities of reactive oxygen species scavenging enzymes were analyzed in leaves of 20-day-old seedlings. Besides, 89 chilling-responsive proteins were revealed from proteomic analysis. All the results highlighted that the growth of seedlings was inhibited due to chilling-decreased enzymes in photosynthesis, carbohydrate metabolism, and energy supplying. The accumulation of osmolytes (i.e., proline, soluble sugar, and glycine betaine) and enhancement of ascorbate-glutathione cycle and glutathione peroxidase/glutathione S-transferase pathway in leaves could minimize oxidative damage of membrane and other molecules under the chilling conditions. In addition, protein synthesis and turnover in cytoplasm and chloroplast were altered to cope with the chilling stress. This study provides valuable information for understanding the chilling-responsive and cross-tolerant mechanisms in monocotyledonous halophyte plant species.
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Affiliation(s)
- Xuejiao Meng
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China
| | - Qi Zhao
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China
| | - Yudan Jin
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China
| | - Juanjuan Yu
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China
| | - Zepeng Yin
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China
| | - Sixue Chen
- Department of Biology, Genetics Institute, Plant Molecular and Cellular Biology Program, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL 32610, USA
| | - Shaojun Dai
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China.
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11
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Dong B, Yang X, Zhu S, Bassham DC, Fang N. Stochastic Optical Reconstruction Microscopy Imaging of Microtubule Arrays in Intact Arabidopsis thaliana Seedling Roots. Sci Rep 2015; 5:15694. [PMID: 26503365 PMCID: PMC4621606 DOI: 10.1038/srep15694] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 09/30/2015] [Indexed: 12/19/2022] Open
Abstract
Super-resolution fluorescence microscopy has generated tremendous success in revealing detailed subcellular structures in animal cells. However, its application to plant cell biology remains extremely limited due to numerous technical challenges, including the generally high fluorescence background of plant cells and the presence of the cell wall. In the current study, stochastic optical reconstruction microscopy (STORM) imaging of intact Arabidopsis thaliana seedling roots with a spatial resolution of 20-40 nm was demonstrated. Using the super-resolution images, the spatial organization of cortical microtubules in different parts of a whole Arabidopsis root tip was analyzed quantitatively, and the results show the dramatic differences in the density and spatial organization of cortical microtubules in cells of different differentiation stages or types. The method developed can be applied to plant cell biological processes, including imaging of additional elements of the cytoskeleton, organelle substructure, and membrane domains.
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Affiliation(s)
- Bin Dong
- Ames Laboratory, US Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - Xiaochen Yang
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa 50011
| | - Shaobin Zhu
- Ames Laboratory, US Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - Diane C. Bassham
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa 50011
- Plant Sciences Institute, Iowa State University, Ames, Iowa 50011
| | - Ning Fang
- Department of Chemistry, Georgia State University, P.O. Box 3965, Atlanta, Georgia 30302
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12
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Qin Y, Dong J. Focusing on the focus: what else beyond the master switches for polar cell growth? MOLECULAR PLANT 2015; 8:582-94. [PMID: 25744359 PMCID: PMC5124495 DOI: 10.1016/j.molp.2014.12.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 12/24/2014] [Accepted: 12/29/2014] [Indexed: 05/21/2023]
Abstract
Cell polarity, often associated with polarized cell expansion/growth in plants, describes the uneven distribution of cellular components, such as proteins, nucleic acids, signaling molecules, vesicles, cytoskeletal elements, and organelles, which may ultimately modulate cell shape, structure, and function. Pollen tubes and root hairs are model cell systems for studying the molecular mechanisms underlying sustained tip growth. The formation of intercalated epidermal pavement cells requires excitatory and inhibitory pathways to coordinate cell expansion within single cells and between cells in contact. Strictly controlled cell expansion is linked to asymmetric cell division in zygotes and stomatal lineages, which require integrated processes of pre-mitotic cellular polarization and division asymmetry. While small GTPase ROPs are recognized as fundamental signaling switches for cell polarity in various cellular and developmental processes in plants, the broader molecular machinery underpinning polarity establishment required for asymmetric division remains largely unknown. Here, we review the widely used ROP signaling pathways in cell polar growth and the recently discovered feedback loops with auxin signaling and PIN effluxers. We discuss the conserved phosphorylation and phospholipid signaling mechanisms for regulating uneven distribution of proteins, as well as the potential roles of novel proteins and MAPKs in the polarity establishment related to asymmetric cell division in plants.
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Affiliation(s)
- Yuan Qin
- Center for Genomics and Biotechnology, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian Province, China
| | - Juan Dong
- Waksman Institute of Microbiology, Rutgers the State University of New Jersey, Piscataway, NJ 08854, USA; The Department of Plant Biology and Pathology, Rutgers the State University of New Jersey, New Brunswick, NJ 08901, USA.
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13
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Green JJ, Cordero Cervantes D, Peters NT, Logan KO, Kropf DL. Dynamic microtubules and endomembrane cycling contribute to polarity establishment and early development of Ectocarpus mitospores. PROTOPLASMA 2013; 250:1035-43. [PMID: 23322087 DOI: 10.1007/s00709-012-0476-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 12/21/2012] [Indexed: 06/01/2023]
Abstract
Many zygotes and spores of brown algae are photosensitive and establish a developmental axis in accordance with directional light cues. Ectocarpus siliculosus is being advanced as a genetic and genomic model organism for investigating brown alga development, and this report investigates photopolarization of the growth axis of mitospores. When exposed to unidirectional light, mitospores photopolarized and established a growth axis such that germination was preferentially localized to the shaded hemisphere of the spore body. The roles of the microtubule cytoskeleton and endomembrane cycling in the photopolarization process were investigated using pharmacological agents. Disruption of microtubule dynamics progressively reduced the percentage of mitospores that photopolarized, while inhibition of vesicle secretion blocked photopolarization nearly completely. Chronic treatment with these pharmacological agents severely affected algal morphogenesis. Microtubules in mitospores and algal filaments were imaged by confocal microscopy. Mitospores contained a radial microtubule array, emanating from a centrosome associated with the nuclear envelope. At germination, the radial array gradually transitioned into a longitudinal array with microtubules extending into the emerging apex. At mitosis, spindles were aligned with the growth axis of cylindrical cells in the filament, and the division plane bisected the spindle axis. These studies demonstrate that dynamic membrane cycling and microtubule assembly play fundamental roles in photopolarization and provide a foundation for future genetic and genomic investigations of this important developmental process.
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Affiliation(s)
- Jeffrey J Green
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
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Elvira PR, Sekida S, Okuda K. Inducible growth mode switches influence Valonia rhizoid differentiation. PROTOPLASMA 2013; 250:407-414. [PMID: 22307207 DOI: 10.1007/s00709-012-0381-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2011] [Accepted: 01/23/2012] [Indexed: 05/31/2023]
Abstract
Cell differentiation and cell type commitment are an integral part of plant growth and development. Investigations on how environmental conditions affect the formation of shoots, roots, and rhizoids can help illustrate how plants determine cell fate and overall morphology. In this study, we evaluated the role of substratum and light on rhizoid differentiation in the coenocytic green alga, Valonia aegagropila. Elongating rhizoids displayed varying growth modes and cell shape upon exposure to different substrata and light conditions. It was found that soft substrata and dark incubation promoted rhizoid elongation via tip growth while subsequent exposure to light prevented tip growth and instead induced swelling in the apical region of rhizoids. Swelling was accompanied by the accumulation of protoplasm in the rhizoid tip through expansion of the cell wall and uninhibited cytoplasmic streaming. Subsequent diffuse growth led to the transformation from slender, rod-shaped rhizoids into spherical thallus-like structures that required photosynthesis. Further manipulation of light regimes caused vacillating cell growth redirections. An elongating V. aegagropila rhizoid cell thus appears capable of growth mode switching that is regulated by immediate environmental conditions thereby influencing ultimate cell shape and function. This is the first description of inducible, multiple growth mode shifts in a single intact plant cell that directly impact its differentiation.
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Affiliation(s)
- Paul Rommel Elvira
- Cell Biology Laboratory, Graduate School of Kuroshio Science, Kochi University, 2-5-1 Akebono-cho, Kochi 780-8520, Japan.
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15
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Abstract
Brown algae are an extremely interesting, but surprisingly poorly explored, group of organisms. They are one of only five eukaryotic lineages to have independently evolved complex multicellularity, which they express through a wide variety of morphologies ranging from uniseriate branched filaments to complex parenchymatous thalli with multiple cell types. Despite their very distinct evolutionary history, brown algae and land plants share a striking amount of developmental features. This has led to an interest in several aspects of brown algal development, including embryogenesis, polarity, cell cycle, asymmetric cell division and a putative role for plant hormone signalling. This review describes how investigations using brown algal models have helped to increase our understanding of the processes controlling early embryo development, in particular polarization, axis formation and asymmetric cell division. Additionally, the diversity of life cycles in the brown lineage and the emergence of Ectocarpus as a powerful model organism, are affording interesting insights on the molecular mechanisms underlying haploid-diploid life cycles. The use of these and other emerging brown algal models will undoubtedly add to our knowledge on the mechanisms that regulate development in multicellular photosynthetic organisms.
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Affiliation(s)
- Kenny A Bogaert
- Phycology Research Group, Department of Biology, Center for Molecular Phylogenetics and Evolution, Ghent University, Ghent, Belgium
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16
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Cherdantsev VG, Grigorieva OV. Morphogenesis of active shells. Biosystems 2012; 109:314-28. [PMID: 22613513 DOI: 10.1016/j.biosystems.2012.04.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 04/21/2012] [Accepted: 04/23/2012] [Indexed: 10/28/2022]
Abstract
We consider the active shell as a single-cell or epithelial sheet surface that, sharing basic properties of stretched elastic shells, is capable of active planar movement owing to recruiting of the new surface elements. As model examples of their morphogenesis, we consider the growth and differentiation of single-cell hairs (trichomes) in plants of the genus Draba, and the epiboly and formation of the dorsoventral polarity in loach. The essential feature of the active shell behavior at both cellular and supracellular levels is regular deviating from the spatially homogeneous form, which is a primary cause of originating of the active mechanical stresses inside the shell in addition to its passive stretching by the intrinsic forces. Analyzing the quantitative morphological data, we derive the equations in which the temporal self-oscillations and spatial differentiation are distinguishable only at the parametric level depending on the proportion of active to passive stresses. In contrast to the ordinary activator-inhibitor systems, the self-oscillation dynamics is principally non-local and, consequently, one-parametric, the shell surface curvature being an analog of the inhibitor, while its spatial variance being an analog of the activator of shaping. Analyzing variability and evolution of the hair cell branching, we argue that the linear ontogeny (succession of the developmental stages) is a secondary evolutionary phenomenon originating from cyclic self-organizing algorithms of the active shell shaping.
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Affiliation(s)
- Vladimir G Cherdantsev
- Department of Biological Evolution, Faculty of Biology, Moscow State University, Moscow 119234, Russia.
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17
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Uváčková L, Takáč T, Boehm N, Obert B, Samaj J. Proteomic and biochemical analysis of maize anthers after cold pretreatment and induction of androgenesis reveals an important role of anti-oxidative enzymes. J Proteomics 2012; 75:1886-94. [PMID: 22252011 DOI: 10.1016/j.jprot.2011.12.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2011] [Revised: 12/22/2011] [Accepted: 12/23/2011] [Indexed: 11/25/2022]
Abstract
In stress conditions, microspores and young pollen grains can be switched from their normal pollen development toward an embryogenic pathway via a process called androgenesis. Androgenic embryos can produce completely homozygous, haploid or double-haploid plants. This study aimed to investigate changes in the abundance of protein species during cold pretreatment and subsequent cultivation of maize anthers on induction media using gel-based proteomics. Proteins upregulated on the third day of anther induction were identified and discussed here. Simultaneous microscopic observations revealed that the first division occurred in microspores within this period. Using 2-D electrophoresis combined with MALDI TOF/TOF MS/MS analysis 19 unique proteins were identified and classified into 8 functional groups. Proteins closely associated with metabolism, protein synthesis and cell structure were the most abundant ones. Importantly, ascorbate peroxidase, an enzyme decomposing hydrogen peroxide, was also upregulated. Isozyme analysis of peroxidases validated the proteomic data and showed increased peroxidase activities during androgenic induction. Further, the isozyme pattern of SOD revealed increased activity of the MnSOD, which could provide hydrogen peroxide as a substrate for in vivo peroxidase reactions (including ascorbate peroxidase). Together, these data reveal the role of enzymes controlling oxidative stress during induction of maize androgenesis.
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Affiliation(s)
- L'ubica Uváčková
- Institute of Plant Genetics and Biotechnology, Slovak Academy of Sciences, Akademická 2, P. O. Box 39A, 95007 Nitra, Slovak Republic
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18
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Nestler J, Schütz W, Hochholdinger F. Conserved and unique features of the maize (Zea mays L.) root hair proteome. J Proteome Res 2011; 10:2525-37. [PMID: 21417484 DOI: 10.1021/pr200003k] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Root hairs are unicellular extensions of specialized epidermis cells. Under limiting conditions, they significantly increase the water and nutrient uptake capacity of plants by enlarging their root surface. Thus far, little is known about the initiation and growth of root hairs in the monocot model species maize. To gain a first insight into the protein composition of these specialized cells, the 2573 most abundant proteins of maize root hairs attached to four-day-old primary roots of the inbred line B73 were identified by combining 1DE with nanoLC-MS/MS in a shotgun proteomic experiment. Among the identified proteins, homologues of 252 proteins have been previously associated with root hair formation and development in other species. Comparison of the root hair reference proteome of the monocot species maize with the previously published root hair proteome of the dicot species soybean revealed conserved, but also unique, protein functions in root hairs of these two major groups of flowering plants.
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Affiliation(s)
- Josefine Nestler
- INRES, Institute of Crop Science and Resource Conservation, Chair for Crop Functional Genomics, University of Bonn, 53115 Bonn, Germany
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19
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Hable WE, Hart PE. Signaling mechanisms in the establishment of plant and fucoid algal polarity. Mol Reprod Dev 2010; 77:751-8. [PMID: 20803733 DOI: 10.1002/mrd.21199] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
The establishment of polarity is a fundamental property of most cells. In tip-growing plant and in fucoid algal cells, polarization specifies a growth pole, the center of localized secretion of new plasma membrane and cell wall material, generating a protrusion with a dome-shaped apex. Although much progress has been made concerning the cellular machinery required to execute tip growth, less is known regarding the signaling mechanisms involved in selecting the growth site and regulating vectorial cell division and expansion. Fucoid algal zygotes use extrinsic cues to orient their growth axes and are thus well-suited for studies of de novo selection of an axis. This process has been investigated largely by both pharmacological and immuno-localization studies. In tip growing plant cells, polarity is often predetermined, as in the formation of root hairs or moss protonema branches. More focus has been on genomic and genetic studies to reveal the molecules involved in expressing a growth axis. Here we review the common roles of the cytoskeleton and signal transduction pathways in the formation of a developmental axis in fucoid algal cells and the control of tip growth in higher plant cells.
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Affiliation(s)
- Whitney E Hable
- University of Massachusetts Dartmouth, Dartmouth, Massachusetts 02747, USA.
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20
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Cherdantsev VG, Grigor’eva OV. Geometry and mechanics of the morphogenesis of active membranes on the example of plant trichome cells of the genus Draba L. Russ J Dev Biol 2010. [DOI: 10.1134/s1062360410030021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Zhukov VA, Shtark OY, Borisov AY, Tikhonovich IA. Molecular genetic mechanisms used by legumes to control early stages of mutually beneficial (mutualistic) symbiosis. RUSS J GENET+ 2009. [DOI: 10.1134/s1022795409110039] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Persia D, Cai G, Del Casino C, Faleri C, Willemse MTM, Cresti M. Sucrose synthase is associated with the cell wall of tobacco pollen tubes. PLANT PHYSIOLOGY 2008; 147:1603-18. [PMID: 18344420 PMCID: PMC2492599 DOI: 10.1104/pp.108.115956] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Accepted: 03/09/2008] [Indexed: 05/20/2023]
Abstract
Sucrose synthase (Sus; EC 2.4.1.13) is a key enzyme of sucrose metabolism in plant cells, providing carbon for respiration and for the synthesis of cell wall polymers and starch. Since Sus is important for plant cell growth, insights into its structure, localization, and features are useful for defining the relationships between nutrients, growth, and cell morphogenesis. We used the pollen tube of tobacco (Nicotiana tabacum) as a cell model to characterize the main features of Sus with regard to cell growth and cell wall synthesis. Apart from its role during sexual reproduction, the pollen tube is a typical tip-growing cell, and the proper construction of its cell wall is essential for correct shaping and direction of growth. The outer cell wall layer of pollen tubes consists of pectins, but the inner layer is composed of cellulose and callose; both polymers require metabolic precursors in the form of UDP-glucose, which is synthesized by Sus. We identified an 88-kD polypeptide in the soluble, plasma membrane and Golgi fraction of pollen tubes. The protein was also found in association with the cell wall. After purification, the protein showed an enzyme activity similar to that of maize (Zea mays) Sus. Distribution of Sus was affected by brefeldin A and depended on the nutrition status of the pollen tube, because an absence of metabolic sugars in the growth medium caused Sus to distribute differently during tube elongation. Analysis by bidimensional electrophoresis indicated that Sus exists as two isoforms, one of which is phosphorylated and more abundant in the cytoplasm and cell wall and the other of which is not phosphorylated and is specific to the plasma membrane. Results indicate that the protein has a role in the construction of the extracellular matrix and thus in the morphogenesis of pollen tubes.
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Affiliation(s)
- Diana Persia
- Dipartimento Scienze Ambientali G. Sarfatti, Università di Siena, 53100 Siena, Italy
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23
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Hochholdinger F, Wen TJ, Zimmermann R, Chimot-Marolle P, da Costa e Silva O, Bruce W, Lamkey KR, Wienand U, Schnable PS. The maize (Zea mays L.) roothairless3 gene encodes a putative GPI-anchored, monocot-specific, COBRA-like protein that significantly affects grain yield. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 54:888-98. [PMID: 18298667 PMCID: PMC2440564 DOI: 10.1111/j.1365-313x.2008.03459.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Revised: 01/24/2008] [Accepted: 02/07/2008] [Indexed: 05/18/2023]
Abstract
The rth3 (roothairless 3) mutant is specifically affected in root hair elongation. We report here the cloning of the rth3 gene via a PCR-based strategy (amplification of insertion mutagenized sites) and demonstrate that it encodes a COBRA-like protein that displays all the structural features of a glycosylphosphatidylinositol anchor. Genes of the COBRA family are involved in various types of cell expansion and cell wall biosynthesis. The rth3 gene belongs to a monocot-specific clade of the COBRA gene family comprising two maize and two rice genes. While the rice (Oryza sativa) gene OsBC1L1 appears to be orthologous to rth3 based on sequence similarity (86% identity at the protein level) and maize/rice synteny, the maize (Zea mays L.) rth3-like gene does not appear to be a functional homolog of rth3 based on their distinct expression profiles. Massively parallel signature sequencing analysis detected rth3 expression in all analyzed tissues, but at relatively low levels, with the most abundant expression in primary roots where the root hair phenotype is manifested. In situ hybridization experiments confine rth3 expression to root hair-forming epidermal cells and lateral root primordia. Remarkably, in replicated field trials involving near-isogenic lines, the rth3 mutant conferred significant losses in grain yield.
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Affiliation(s)
- Frank Hochholdinger
- Center for Plant Molecular Biology, Department of General Genetics, Eberhard-Karls-University Tuebingen72076 Tuebingen, Germany
| | - Tsui-Jung Wen
- Department of Agronomy, Iowa State UniversityAmes, IA 50011, USA
| | - Roman Zimmermann
- Center for Plant Molecular Biology, Department of General Genetics, Eberhard-Karls-University Tuebingen72076 Tuebingen, Germany
| | - Patricia Chimot-Marolle
- Institute for General Botany and Botanical Garden, University of Hamburg22609 Hamburg, Germany
| | | | - Wesley Bruce
- Pioneer Hi-Bred International, Inc. – a DuPont CompanyJohnston, IA 50131, USA
| | - Kendall R Lamkey
- Department of Agronomy, Iowa State UniversityAmes, IA 50011, USA
| | - Udo Wienand
- Institute for General Botany and Botanical Garden, University of Hamburg22609 Hamburg, Germany
| | - Patrick S Schnable
- Department of Agronomy, Iowa State UniversityAmes, IA 50011, USA
- Pioneer Hi-Bred International, Inc. – a DuPont CompanyJohnston, IA 50131, USA
- Department of Genetics, Development, and Cell Biology, Iowa State UniversityAmes, IA 50011, USA
- Center for Plant Genomics, Iowa State University, Ames, IA 50011-36506, USA
- *For correspondence (fax +1 515 294 5256; e-mail )
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Timmers ACJ, Vallotton P, Heym C, Menzel D. Microtubule dynamics in root hairs of Medicago truncatula. Eur J Cell Biol 2007; 86:69-83. [PMID: 17218039 DOI: 10.1016/j.ejcb.2006.11.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2006] [Revised: 11/14/2006] [Accepted: 11/14/2006] [Indexed: 12/25/2022] Open
Abstract
The microtubular cytoskeleton plays an important role in the development of tip-growing plant cells, but knowledge about its dynamics is incomplete. In this study, root hairs of the legume Medicago truncatula have been chosen for a detailed analysis of microtubular cytoskeleton dynamics using GFP-MBD and EB1-YFP as markers and 4D imaging. The microtubular cytoskeleton appears mainly to be composed of bundles which form tracks along which new microtubules polymerise. Polymerisation rates of microtubules are highest in the tip of growing root hairs. Treatment of root hairs with Nod factor and latrunculin B result in a twofold decrease in polymerisation rate. Nonetheless, no direct, physical interaction between the actin filament cytoskeleton and microtubules could be observed. A new picture of how the plant cytoskeleton is organised in apically growing root hairs emerges from these observations, revealing similarities with the organisation in other, non-plant, tip-growing cells.
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Affiliation(s)
- Antonius C J Timmers
- Laboratory of Plant-Microorganism Interactions, CNRS INRA, UMR2594, 24 Chemin de Borde Rouge, BP 52627, F-31326 Castanet-Tolosan, France.
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26
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Kim SY, Sivaguru M, Stacey G. Extracellular ATP in plants. Visualization, localization, and analysis of physiological significance in growth and signaling. PLANT PHYSIOLOGY 2006; 142:984-92. [PMID: 16963521 PMCID: PMC1630726 DOI: 10.1104/pp.106.085670] [Citation(s) in RCA: 169] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Extracellular ATP (eATP) in animals is well documented and known to play an important role in cellular signaling (e.g. at the nerve synapse). The existence of eATP has been postulated in plants; however, there is no definitive experimental evidence for its presence or an explanation as to how such a polar molecule could exit the plant cell and what physiological role it may play in plant growth and development. The presence of eATP in plants (Medicago truncatula) was detected by constructing a novel reporter; i.e. fusing a cellulose-binding domain peptide to the ATP-requiring enzyme luciferase. Application of this reporter to plant roots allowed visualization of eATP in the presence of the substrate luciferin. Luciferase activity could be detected in the interstitial spaces between plant epidermal cells and predominantly at the regions of actively growing cells. The levels of eATP were closely correlated with regions of active growth and cell expansion. Pharmacological compounds known to alter cytoplasmic calcium levels revealed that ATP release is a calcium-dependent process and may occur through vesicular fusion, an important step in the polar growth of actively growing root hairs. Reactive oxygen species (ROS) activity at the root hair tip is not only essential for root hair growth, but also dependent on the cytoplasmic calcium levels. Whereas application of exogenous ATP and a chitin mixture increased ROS activity in root hairs, no changes were observed in response to adenosine, AMP, ADP, and nonhydrolyzable ATP (betagammameATP). However, application of exogenous potato (Solanum tuberosum) apyrase (ATPase) decreased ROS activity, suggesting that cytoplasmic calcium gradients and ROS activity are closely associated with eATP release.
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Affiliation(s)
- Sung-Yong Kim
- National Center for Soybean Biotechnology and Division of Plant Sciences , University of Missouri, Columbia, Missouri 65211, USA
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Fang WP, Jiang CJ, Yu M, Ye AH, Wan ZX. Differentially expression of Tua1, a tubulin-encoding gene, during flowering of tea plant Camellia sinensis (L.) O. Kuntze using cDNA amplified fragment length polymorphism technique. Acta Biochim Biophys Sin (Shanghai) 2006; 38:653-62. [PMID: 16953305 DOI: 10.1111/j.1745-7270.2006.00202.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The complementary DNA (cDNA) amplified fragment length polymorphism technique was used to isolate transcript-derived fragments corresponding to genes involved in the flowering of tea plant. Comparative sequence analysis of an approximately 300 bp differential fragment amplified by primer combination E11M11 revealed 80%-84% similarity to the corresponding part of an a-tubulin gene of other species. The complete cDNA sequence of this a-tubulin was cloned by the rapid amplification of cDNA ends technique; its full length is 1537 bp and contains an open reading frame of 450 amino acid residues with two N-glycosylation sites and four protein kinase C phosphorylation sites. The deduced amino acid sequences did show significant homology to the a-tubulin from other plants that has been reported to be a pollen-specific protein and could be correlated with plant cytoplasm-nucleus-interacted male sterility. We named this complete cDNA Tua1. The nucleotide and amino acid sequence data of Tua1 have been recorded in the GenBank sequence database. This Tua1 gene was cloned into the pET-32a expression system and expressed in Escherichia coli BL21trxB(DE3). The molecular weight of expressed protein was deduced to be approximately 49 kDa. Western blot analysis was used to identify the temporal expression of Tua1 in tea plant. Further studies of the effect of Tua1 protein on pollen tube growth indicated the Tua1 solution obviously promoted the growth of tea pollen tube.
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Affiliation(s)
- Wan-Ping Fang
- Key Laboratory of Tea Biochemistry and Biotechnology, Ministry of Agriculture, Anhui Agricultural University, Hefei 230036, China
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28
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Peters NT, Kropf DL. Kinesin-5 motors are required for organization of spindle microtubules in Silvetia compressa zygotes. BMC PLANT BIOLOGY 2006; 6:19. [PMID: 16945151 PMCID: PMC1564386 DOI: 10.1186/1471-2229-6-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Accepted: 08/31/2006] [Indexed: 05/11/2023]
Abstract
BACKGROUND Monastrol, a chemical inhibitor specific to the Kinesin-5 family of motor proteins, was used to examine the functional roles of Kinesin-5 proteins during the first, asymmetric cell division cycle in the brown alga Silvetia compressa. RESULTS Monastrol treatment had no effect on developing zygotes prior to entry into mitosis. After mitosis entry, monastrol treatment led to formation of monasters and cell cycle arrest in a dose dependent fashion. These findings indicate that Kinesin-5 motors maintain spindle bipolarity, and are consistent with reports in animal cells. At low drug concentrations that permitted cell division, spindle position was highly displaced from normal, resulting in abnormal division planes. Strikingly, application of monastrol also led to formation of numerous cytasters throughout the cytoplasm and multipolar spindles, uncovering a novel effect of monastrol treatment not observed in animal cells. CONCLUSION We postulate that monastrol treatment causes spindle poles to break apart forming cytasters, some of which capture chromosomes and become supernumerary spindle poles. Thus, in addition to maintaining spindle bipolarity, Kinesin-5 members in S. compressa likely organize microtubules at spindle poles. To our knowledge, this is the first functional characterization of the Kinesin-5 family in stramenopiles.
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Affiliation(s)
- Nick T Peters
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA.
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29
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Katsaros C, Karyophyllis D, Galatis B. Cytoskeleton and morphogenesis in brown algae. ANNALS OF BOTANY 2006; 97:679-93. [PMID: 16467352 PMCID: PMC2803427 DOI: 10.1093/aob/mcl023] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2005] [Revised: 11/05/2005] [Accepted: 11/28/2005] [Indexed: 05/06/2023]
Abstract
BACKGROUND Morphogenesis on a cellular level includes processes in which cytoskeleton and cell wall expansion are strongly involved. In brown algal zygotes, microtubules (MTs) and actin filaments (AFs) participate in polarity axis fixation, cell division and tip growth. Brown algal vegetative cells lack a cortical MT cytoskeleton, and are characterized by centriole-bearing centrosomes, which function as microtubule organizing centres. SCOPE Extensive electron microscope and immunofluorescence studies of MT organization in different types of brown algal cells have shown that MTs constitute a major cytoskeletal component, indispensable for cell morphogenesis. Apart from participating in mitosis and cytokinesis, they are also involved in the expression and maintenance of polarity of particular cell types. Disruption of MTs after Nocodazole treatment inhibits cell growth, causing bulging and/or bending of apical cells, thickening of the tip cell wall, and affecting the nuclear positioning. Staining of F-actin using Rhodamine-Phalloidin, revealed a rich network consisting of perinuclear, endoplasmic and cortical AFs. AFs participate in mitosis by the organization of an F-actin spindle and in cytokinesis by an F-actin disc. They are also involved in the maintenance of polarity of apical cells, as well as in lateral branch initiation. The cortical system of AFs was found related to the orientation of cellulose microfibrils (MFs), and therefore to cell wall morphogenesis. This is expressed by the coincidence in the orientation between cortical AFs and the depositing MFs. Treatment with cytochalasin B inhibits mitosis and cytokinesis, as well as tip growth of apical cells, and causes abnormal deposition of MFs. CONCLUSIONS Both the cytoskeletal elements studied so far, i.e. MTs and AFs are implicated in brown algal cell morphogenesis, expressed in their relationship with cell wall morphogenesis, polarization, spindle organization and cytokinetic mechanism. The novelty is the role of AFs and their possible co-operation with MTs.
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Affiliation(s)
- Christos Katsaros
- University of Athens, Faculty of Biology, Department of Botany, Athens 157 84, Greece.
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30
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Panteris E, Galatis B. The morphogenesis of lobed plant cells in the mesophyll and epidermis: organization and distinct roles of cortical microtubules and actin filaments. THE NEW PHYTOLOGIST 2005; 167:721-32. [PMID: 16101909 DOI: 10.1111/j.1469-8137.2005.01464.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The morphogenesis of lobed plant cells has been considered to be controlled by microtubule (MT) and/or actin filament (AF) organization. In this article, a comprehensive mechanism is proposed, in which distinct roles are played by these cytoskeletal components. First, cortical MT bundles and, in the case of pavement cells, radial MT arrays combined with MT bundles determine the deposition of local cell wall thickenings, the cellulose microfibrils of which copy the orientation of underlying MTs. Cell growth is thus locally prevented and, consequently, lobes and constrictions are formed. Arch-like tangential expansion is locally imposed at the external periclinal wall of pavement cells by the radial arrangement of cellulose microfibrils at every wall thickening. Whenever further elongation of the original cell lobes occurs, AF patches assemble at the tips of growing lobes. Intercellular space formation is promoted or prevented by the opposite or alternate, respectively, arrangement of cortical MT arrays between neighboring cells. The genes that are possibly involved in the molecular regulation of the above morphogenetic procedure by MT and AF array organization are reviewed.
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Affiliation(s)
- Emmanuel Panteris
- University of Athens, Faculty of Biology, Department of Botany, Athens GR-15784, Greece
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31
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Wen TJ, Hochholdinger F, Sauer M, Bruce W, Schnable PS. The roothairless1 gene of maize encodes a homolog of sec3, which is involved in polar exocytosis. PLANT PHYSIOLOGY 2005; 138:1637-43. [PMID: 15980192 PMCID: PMC1176433 DOI: 10.1104/pp.105.062174] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The roothairless1 (rth1) mutant is impaired in root hair elongation and exhibits other growth abnormalities. Unicellular root hairs elongate via localized tip growth, a process mediated by polar exocytosis of secretory vesicles. We report here the cloning of the rth1 gene that encodes a sec3 homolog. In yeast (Saccharomyces cerevisiae) and mammals, sec3 is a subunit of the exocyst complex, which tethers exocytotic vesicles prior to their fusion. The cloning of the rth1 gene associates the homologs of exocyst subunits to an exocytotic process in plant development and supports the hypothesis that exocyst-like proteins are involved in plant exocytosis. Proteomic analyses identified four proteins that accumulate to different levels in wild-type and rth1 primary roots. The preferential accumulation in the rth1 mutant proteome of a negative regulator of the cell cycle (a prohibitin) may at least partially explain the delayed development and flowering of the rth1 mutant.
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Affiliation(s)
- Tsui-Jung Wen
- Department of Agronomy , Iowa State University, Ames, Iowa 50011, USA
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32
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Van Bruaene N, Joss G, Van Oostveldt P. Reorganization and in vivo dynamics of microtubules during Arabidopsis root hair development. PLANT PHYSIOLOGY 2004; 136:3905-19. [PMID: 15557102 PMCID: PMC535824 DOI: 10.1104/pp.103.031591] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2003] [Revised: 06/30/2004] [Accepted: 07/21/2004] [Indexed: 05/17/2023]
Abstract
Root hairs emerge from epidermal root cells (trichoblasts) and differentiate by highly localized tip growth. Microtubules (MTs) are essential for establishing and maintaining the growth polarity of root hairs. The current knowledge about the configuration of the MT cytoskeleton during root hair development is largely based on experiments on fixed material, and reorganization and in vivo dynamics of MTs during root hair development is at present unclear. This in vivo study provides new insights into the mechanisms of MT (re)organization during root hair development in Arabidopsis (Arabidopsis thaliana). Expression of a binding site of the MT-associated protein-4 tagged with green fluorescent protein enabled imaging of MT nucleation, growth, and shortening and revealed distinct MT configurations. Depending on the dynamics of the different MT populations during root hair development, either repeated two-dimensional (x, y, t) or repeated three-dimensional (x, y, z, t) scanning was performed. Furthermore, a new image evaluation tool was developed to reveal important data on MT instability. The data show how MTs reorient after apparent contact with other MTs and support a model for MT alignment based on repeated reorientation of dynamic MT growth.
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Affiliation(s)
- Nathalie Van Bruaene
- Laboratory for Biochemistry and Molecular Cytology, Ghent University, 9000 Gent, Belgium.
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33
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Kim HJ, Triplett BA. Characterization of GhRac1 GTPase expressed in developing cotton (Gossypium hirsutum L.) fibers. ACTA ACUST UNITED AC 2004; 1679:214-21. [PMID: 15358513 DOI: 10.1016/j.bbaexp.2004.06.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2004] [Revised: 06/03/2004] [Accepted: 06/24/2004] [Indexed: 10/26/2022]
Abstract
Cytoskeleton assembly plays an important role in determining cotton fiber cell length and morphology and is developmentally regulated. As in other plant cells, it is not clear how cytoskeletal assembly in fibers is regulated. Recently, several Rac/Rop GTPases in Arabidopsis were shown to regulate isotropic and polar cell growth of root hairs and pollen tubes by controlling assembly of the cytoskeleton. GhRac1, isolated from cottonseeds, is a member of the Rac/Rop GTPase family and is abundantly expressed in rapidly growing cotton tissues. GhRac1 shows the greatest sequence similarity to the group IV subfamily of Arabidopsis Rac/Rop genes. Overexpression of GhRac1 in E. coli led to the production of a functional GTPase as shown by in vitro enzyme activity assay. In contrast to other Rac/Rop GTPases found in cotton fiber, GhRac1 is highly expressed during the elongation stage of fiber development with expression decreasing dramatically when the rate of fiber elongation declines. The association of highest GhRac1 expression during stages of maximal cotton fiber elongation suggests that GhRac1 GTPase may be a potential regulator of fiber elongation by controlling cytoskeletal assembly.
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Affiliation(s)
- Hee Jin Kim
- USDA-ARS, Southern Regional Research Center, New Orleans, LA 70124, USA
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34
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35
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Preuss ML, Serna J, Falbel TG, Bednarek SY, Nielsen E. The Arabidopsis Rab GTPase RabA4b localizes to the tips of growing root hair cells. THE PLANT CELL 2004; 16:1589-603. [PMID: 15155878 PMCID: PMC490048 DOI: 10.1105/tpc.021634] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2004] [Accepted: 03/29/2004] [Indexed: 05/17/2023]
Abstract
Spatial and temporal control of cell wall deposition plays a unique and critical role during growth and development in plants. To characterize membrane trafficking pathways involved in these processes, we have examined the function of a plant Rab GTPase, RabA4b, during polarized expansion in developing root hair cells. Whereas a small fraction of RabA4b cofractionated with Golgi membrane marker proteins, the majority of this protein labeled a unique membrane compartment that did not cofractionate with the previously characterized trans-Golgi network syntaxin proteins SYP41 and SYP51. An enhanced yellow fluorescent protein (EYFP)-RabA4b fusion protein specifically localizes to the tips of growing root hair cells in Arabidopsis thaliana. Tip-localized EYFP-RabA4b disappears in mature root hair cells that have stopped expanding, and polar localization of the EYFP-RabA4b is disrupted by latrunculin B treatment. Loss of tip localization of EYFP-RabA4b was correlated with inhibition of expansion; upon washout of the inhibitor, root hair expansion recovered only after tip localization of the EYFP-RabA4b compartments was reestablished. Furthermore, in mutants with defective root hair morphology, EYFP-RabA4b was improperly localized or was absent from the tips of root hair cells. We propose that RabA4b regulates membrane trafficking through a compartment involved in the polarized secretion of cell wall components in plant cells.
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Affiliation(s)
- Mary L Preuss
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
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36
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Li W, Wang Z, Jia S. Effect of GbKTN1 fromGossypium barbadense on cell elongation of fission yeast (Schizosaccharomyces pombe). CHINESE SCIENCE BULLETIN-CHINESE 2004. [DOI: 10.1007/bf02901738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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37
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Kang BH, Rancour DM, Bednarek SY. The dynamin-like protein ADL1C is essential for plasma membrane maintenance during pollen maturation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2003; 35:1-15. [PMID: 12834397 DOI: 10.1046/j.1365-313x.2003.01775.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Dynamin-related GTPases regulate a wide variety of dynamic membrane processes in eukaryotes. Here, we investigated the function of ADL1C, a member of the Arabidopsis 68 kDa dynamin-like protein family. Analysis of heterozygous adl1C-1 indicates that the mutation specifically affects post-meiotic male gametogenesis. Fifty percent of the mature pollen from heterozygous adl1C-1 androecia are shriveled and fail to germinate in vitro. During microspore maturation, adl1C-1 pollen grains display defects in the plasma membrane and intine morphology, suggesting that ADL1C is essential for the formation and maintenance of the pollen cell surface and viability during desiccation. Consistent with a role in cell-surface dynamics, immunofluorescence microscopy indicates that ADL1C is localized to the cell plate of dividing somatic cells and to the tip of expanding root hairs. We propose that ADL1C functions in plasma membrane dynamics, and we discuss the role of the ADL1 family in plant growth and development.
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Affiliation(s)
- Byung-Ho Kang
- Department of Biochemistry, University of Wisconsin-Madison 433 Babcock Dr., Madison, WI 53706, USA
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38
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Baluska F, Wojtaszek P, Volkmann D, Barlow P. The architecture of polarized cell growth: the unique status of elongating plant cells. Bioessays 2003; 25:569-76. [PMID: 12766946 DOI: 10.1002/bies.10282] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Polarity is an inherent feature of almost all prokaryotic and eukaryotic cells. In most eukaryotic cells, growth polarity is due to the assembly of actin-based growing domains at particular locations on the cell periphery. A contrasting scenario is that growth polarity results from the establishment of non-growing domains, which are actively maintained at opposite end-poles of the cell. This latter mode of growth is common in rod-shaped bacteria and, surprisingly, also in the majority of plant cells, which elongate along the apical-basal axes of plant organs. The available data indicate that the non-growing end-pole domains of plant cells are sites of intense endocytosis and recycling. These actin-enriched end-poles serve also as signaling platforms, allowing bidirectional exchange of diverse signals along the supracellular domains of longitudinal cell files. It is proposed that these actively remodeled end-poles of elongating plant cells remotely resemble neuronal synapses.
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Affiliation(s)
- Frantisek Baluska
- Institute of Botany, Department of Plant Cell Biology, Rheinische Friedrich-Wilhelms-University of Bonn, 53115 Bonn, Germany.
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39
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Kang BH, Busse JS, Bednarek SY. Members of the Arabidopsis dynamin-like gene family, ADL1, are essential for plant cytokinesis and polarized cell growth. THE PLANT CELL 2003; 15:899-913. [PMID: 12671086 PMCID: PMC524700 DOI: 10.1105/tpc.009670] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Polarized membrane trafficking during plant cytokinesis and cell expansion are critical for plant morphogenesis, yet very little is known about the molecular mechanisms that guide this process. Dynamin and dynamin-related proteins are large GTP binding proteins that are involved in membrane trafficking. Here, we show that two functionally redundant members of the Arabidopsis dynamin-related protein family, ADL1A and ADL1E, are essential for polar cell expansion and cell plate biogenesis. adl1A-2 adl1E-1 double mutants show defects in cell plate assembly, cell wall formation, and plasma membrane recycling. Using a functional green fluorescent protein fusion protein, we show that the distribution of ADL1A is dynamic and that the protein is localized asymmetrically to the plasma membrane of newly formed and mature root cells. We propose that ADL1-mediated membrane recycling is essential for plasma membrane formation and maintenance in plants.
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Affiliation(s)
- Byung-Ho Kang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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40
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Hasezawa S, Kumagai F. Dynamic changes and the role of the cytoskeleton during the cell cycle in higher plant cells. INTERNATIONAL REVIEW OF CYTOLOGY 2002; 214:161-91. [PMID: 11893165 DOI: 10.1016/s0074-7696(02)14005-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
In higher plant cells microtubules (MTs) show dynamic structural changes during cell cycle progression and play significant roles in cell morphogenesis. The cortical MT (CMT), preprophase band (PPB), and phragmoplast, all of which are plant-specific MT structures, can be observed during interphase, from the late G2 phase to prophase, and from anaphase to telophase, respectively. The CMT controls cell shape, either irreversibly or reversibly, by orientating cellulose microfibril (CMF) deposition in the cell wall; the PPB is involved in determining the site of division; and the phragmoplast forms the cell plate at cytokinesis. The appearance and disappearance of these MT structures during the cell cycle have been extensively studied by immunofluorescence microscopy using highly synchronized tobacco BY-2 cells. Indeed, these studies, together with visualization of MT dynamics in living plant cells using the green fluorescent protein, have revealed much about the modes of MT structural organization, for example, of CMTs at the M/G1 interphase. The microfilaments which also show dynamic changes during the cell cycle, being similar to MTs at particular stages and different at other stages, appear to play roles in supporting MTs. In this article, we summarize our ongoing research and that of related studies of the structure and function of the plant cytoskeleton during cell cycle progression.
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Affiliation(s)
- Seiichiro Hasezawa
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
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41
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Abstract
Microtubules and microfilaments play important roles in cell morphogenesis. The picture emerging from drug studies and molecular-genetic analyses of mutant higher plants defective in cell morphogenesis shows that the roles played by them remain the same in both tip-growing and diffuse-growing cells. Microtubules are important for establishing and maintaining growth polarity whereas actin microfilaments deliver the materials required for growth to specified sites. The recent cloning of several cell morphogenesis genes has revealed that conserved mechanisms as well as novel signal transduction pathways spatially organize the plant cytoskeleton.
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Affiliation(s)
- Jaideep Mathur
- Botanical Institute III, University of Köln, Gyrhofstrasse 15, 50931, Köln, Germany
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42
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Sieberer BJ, Timmers ACJ, Lhuissier FGP, Emons AMC. Endoplasmic microtubules configure the subapical cytoplasm and are required for fast growth of Medicago truncatula root hairs. PLANT PHYSIOLOGY 2002; 130:977-88. [PMID: 12376661 PMCID: PMC166623 DOI: 10.1104/pp.004267] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2002] [Revised: 04/09/2002] [Accepted: 06/24/2002] [Indexed: 05/17/2023]
Abstract
To investigate the configuration and function of microtubules (MTs) in tip-growing Medicago truncatula root hairs, we used immunocytochemistry or in vivo decoration by a GFP linked to a MT-binding domain. The two approaches gave similar results and allowed the study of MTs during hair development. Cortical MTs (CMTs) are present in all developmental stages. During the transition from bulge to a tip-growing root hair, endoplasmic MTs (EMTs) appear at the tip of the young hair and remain there until growth arrest. EMTs are a specific feature of tip-growing hairs, forming a three-dimensional array throughout the subapical cytoplasmic dense region. During growth arrest, EMTs, together with the subapical cytoplasmic dense region, progressively disappear, whereas CMTs extend further toward the tip. In full-grown root hairs, CMTs, the only remaining population of MTs, converge at the tip and their density decreases over time. Upon treatment of growing hairs with 1 microM oryzalin, EMTs disappear, but CMTs remain present. The subapical cytoplasmic dense region becomes very short, the distance nucleus tip increases, growth slows down, and the nucleus still follows the advancing tip, though at a much larger distance. Taxol has no effect on the cytoarchitecture of growing hairs; the subapical cytoplasmic dense region remains intact, the nucleus keeps its distance from the tip, but growth rate drops to the same extent as in hairs treated with 1 microM oryzalin. The role of EMTs in growing root hairs is discussed.
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Affiliation(s)
- Björn J Sieberer
- Laboratory of Plant Cell Biology, Wageningen University, Arboretumlaan 4, 6703 BD Wageningen, The Netherlands
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43
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Abstract
Plants lack the Rho and Rac/Cdc42 GTPases that are so important in diverse signal transduction processes in animals. A plant-specific group of Rho-like proteins - Rops - shows striking similarities to their animal relatives, but also exciting differences in their regulation and signal transduction.
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Affiliation(s)
- Jaideep Mathur
- University of Köln, Botanical Institute III, Gyrhofstr. 15, D-50931, Köln, Germany
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44
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Abstract
The functions of microtubules and actin filaments during various processes that are essential for the growth, reproduction and survival of single plant cells have been well characterized. A large number of plant structural cytoskeletal or cytoskeleton-associated proteins, as well as genes encoding such proteins, have been identified. Although many of these genes and proteins have been partially characterized with respect to their functions, a coherent picture of how they interact to execute cytoskeletal functions in plant cells has yet to emerge. Cytoskeleton-controlled cellular processes are expected to play crucial roles during plant cell differentiation and organogenesis, but what exactly these roles are has only been investigated in a limited number of studies in the whole plant context. The intent of this review is to discuss the results of these studies in the light of what is known about the cellular functions of the plant cytoskeleton, and about the proteins and genes that are required for them. Directions are outlined for future work to advance our understanding of how the cytoskeleton contributes to plant organogenesis and development.
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Affiliation(s)
- Benedikt Kost
- Laboratory of Plant Cell Biology, Institute of Molecular Biology, National University of Singapore, 1 Research Link, Singapore 117 604
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45
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Fu Y, Yang Z. Rop GTPase: a master switch of cell polarity development in plants. TRENDS IN PLANT SCIENCE 2001; 6:545-547. [PMID: 11738369 DOI: 10.1016/s1360-1385(01)02130-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Cell polarity is fundamentally important to plant growth and development, yet the mechanism governing its development is understood poorly. Several studies have revealed a role for Rop GTPases in pollen polar tip growth. Rop is also localized to the future site of root hair development and the tip of root hairs, and expression of constitutively active Rop mutants impacts on the morphogenesis of tip-growing root hairs as well as on non-tip-growing cells. These findings highlight the importance of Rop as a common switch in cell polarity control in plants.
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Affiliation(s)
- Y Fu
- Dept of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
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46
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Abstract
Plant cells adopt a diversity of different shapes that are adapted to their specific functions. Central to the development of specialised form is the modification of cell-wall composition and organisation. A number of recent papers emphasise the importance of the cell wall to cell shaping, in the definition of both localised regions that are expandable and regions that are more resistant to mechanical forces. The organisation and activity of the cytoskeleton, and the activity of signalling pathways, are also essential in defining regions of the cell wall that will grow and those that will not. Although turgor has long been assumed to be a rather passive contributor to cell shaping, recent reports show that, in some cells, differential changes in turgor may have a role in establishing specialised cell form.
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Affiliation(s)
- C Martin
- Department of Cell and Developmental Biology, John Innes Centre, Colney, NR4 7UH, Norwich, UK
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47
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Bick I, Thiel G, Homann U. Cytochalasin D attenuates the desensitisation of pressure-stimulated vesicle fusion in guard cell protoplasts. Eur J Cell Biol 2001; 80:521-6. [PMID: 11561903 DOI: 10.1078/0171-9335-00189] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Fusion of vesicular membranes with the plasma membrane during pressure-driven swelling of guard cell protoplasts was studied using patch clamp capacitance measurements. Hydrostatic pressure pulses were applied via the patch pipette and resulted in an immediate and linear increase in membrane capacitance, a parameter proportional to the surface area. In any given protoplast, pressure-stimulated increases in membrane capacitance could be provoked repetitively. However, the rate of rise in capacitance upon the same strength of stimulation decreased exponentially with time (tau = 4 min) for subsequent pressure stimuli. This process was the result of a desensitisation of the plasma membrane to mechanical forces. Incubation of guard cell protoplasts in cytochalasin D, which depolymerises actin filaments, nearly abolished this desensitisation process. These results suggest that membrane stretch initiates a reactive process that may fortify or stabilise the plasma membrane of guard cell protoplasts.
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Affiliation(s)
- I Bick
- Albrecht-von-Heller Institut of Plant Sciences, University of Göttingen, Germany
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48
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Torralba S, Heath IB, Ottensmeyer FP. Ca(2+) shuttling in vesicles during tip growth in Neurospora crassa. Fungal Genet Biol 2001; 33:181-93. [PMID: 11495575 DOI: 10.1006/fgbi.2001.1282] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tip-growing organisms maintain an apparently essential tip-high gradient of cytoplasmic Ca(2+). In the oomycete Saprolegnia ferax, in pollen tubes and root hairs, the gradient is produced by a tip-localized Ca(2+) influx from the external medium. Such a gradient is normally dispensable for Neurospora crassa hyphae, which may maintain their Ca(2+) gradient by some form of internal recycling. We localized Ca(2+) in N. crassa hyphae at the ultrastructural level using two techniques (a) electron spectroscopic imaging of freeze-dried hyphae and (b) pyroantimoniate precipitation. The results of both methods support the presence of Ca(2+) in the wall vesicles and Golgi body equivalents, providing a plausible mechanism for the generation and maintenance of the gradient by Ca(2+) shuttling in vesicles to the apex, without exogenous Ca(2+) influx. Ca(2+) sequestration into the vesicles seems to be dependent on Ca(2+)-ATPases since cyclopiazonic acid, a specific inhibitor of Ca(2+) pumps, eliminated all Ca(2+) deposits from the vesicles of N. crassa.
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Affiliation(s)
- S Torralba
- Department of Biology, York University, Toronto, Ontario, M3J 1P3, Canada
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Molendijk AJ, Bischoff F, Rajendrakumar CS, Friml J, Braun M, Gilroy S, Palme K. Arabidopsis thaliana Rop GTPases are localized to tips of root hairs and control polar growth. EMBO J 2001; 20:2779-88. [PMID: 11387211 PMCID: PMC125484 DOI: 10.1093/emboj/20.11.2779] [Citation(s) in RCA: 296] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2001] [Revised: 04/03/2001] [Accepted: 04/03/2001] [Indexed: 01/09/2023] Open
Abstract
Plants contain a novel unique subfamily of Rho GTPases, vital components of cellular signalling networks. Here we report a general role for some members of this family in polarized plant growth processes. We show that Arabidopsis AtRop4 and AtRop6 encode functional GTPases with similar intrinsic GTP hydrolysis rates. We localized AtRop proteins in root meristem cells to the cross-wall and cell plate membranes. Polar localization of AtRops in trichoblasts specifies the growth sites for emerging root hairs. These sites were visible before budding and elongation of the Arabidopsis root hair when AtRops accumulated at their tips. Expression of constitutively active AtRop4 and AtRop6 mutant proteins in root hairs of transgenic Arabidopsis plants abolished polarized growth and delocalized the tip-focused Ca2+ gradient. Polar localization of AtRops was inhibited by brefeldin A, but not by other drugs such as latrunculin B, cytochalasin D or caffeine. Our results demonstrate a general function of AtRop GTPases in tip growth and in polar diffuse growth.
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Affiliation(s)
- Arthur J. Molendijk
- Max-Delbrück-Laboratorium in der Max-Planck-Gesellschaft and Max-Planck Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Botanisches Institut, Zellbiologie der Pflanzen, Universität Bonn, Venusbergweg 22, D-53115 Bonn, Germany and Department of Biology, The Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA Corresponding author e-mail:
| | - Friedrich Bischoff
- Max-Delbrück-Laboratorium in der Max-Planck-Gesellschaft and Max-Planck Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Botanisches Institut, Zellbiologie der Pflanzen, Universität Bonn, Venusbergweg 22, D-53115 Bonn, Germany and Department of Biology, The Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA Corresponding author e-mail:
| | - Chadalavada S.V. Rajendrakumar
- Max-Delbrück-Laboratorium in der Max-Planck-Gesellschaft and Max-Planck Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Botanisches Institut, Zellbiologie der Pflanzen, Universität Bonn, Venusbergweg 22, D-53115 Bonn, Germany and Department of Biology, The Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA Corresponding author e-mail:
| | - Jiří Friml
- Max-Delbrück-Laboratorium in der Max-Planck-Gesellschaft and Max-Planck Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Botanisches Institut, Zellbiologie der Pflanzen, Universität Bonn, Venusbergweg 22, D-53115 Bonn, Germany and Department of Biology, The Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA Corresponding author e-mail:
| | - Markus Braun
- Max-Delbrück-Laboratorium in der Max-Planck-Gesellschaft and Max-Planck Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Botanisches Institut, Zellbiologie der Pflanzen, Universität Bonn, Venusbergweg 22, D-53115 Bonn, Germany and Department of Biology, The Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA Corresponding author e-mail:
| | - Simon Gilroy
- Max-Delbrück-Laboratorium in der Max-Planck-Gesellschaft and Max-Planck Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Botanisches Institut, Zellbiologie der Pflanzen, Universität Bonn, Venusbergweg 22, D-53115 Bonn, Germany and Department of Biology, The Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA Corresponding author e-mail:
| | - Klaus Palme
- Max-Delbrück-Laboratorium in der Max-Planck-Gesellschaft and Max-Planck Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Botanisches Institut, Zellbiologie der Pflanzen, Universität Bonn, Venusbergweg 22, D-53115 Bonn, Germany and Department of Biology, The Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA Corresponding author e-mail:
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Abstract
Hyphal tip growth is a complex process involving finely regulated interactions between the synthesis and expansion of cell wall and plasma membrane, diverse intracellular movements, and turgor regulation. F-actin is a major regulator and integrator of these processes. It directly contributes to (a) tip morphogenesis, most likely by participation in an apical membrane skeleton that reinforces the apical plasma membrane, (b) the transport and exocytosis of vesicles that contribute plasma membrane and cell wall material to the hyphal tips, (c) the localization of plasma membrane proteins in the tips, and (d) cytoplasmic and organelle migration and positioning. The pattern of reorganization of F-actin prior to formation of new tips during branch initiation also indicates a critical role in early stages of assembly of the tip apparatus. One of the universal characteristics of all critically examined tip-growing cells, including fungal hyphae, is the obligatory presence of a tip-high gradient of cytoplasmic Ca2+ that probably regulates both actin and nonactin components of the apparatus, and the formation of which may also initiate new tips. This review discusses the diversity of evidence behind these concepts.
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Affiliation(s)
- S Torralba
- Biology Department, York University, Toronto, Ontario, M3J 1P3 Canada
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