1
|
Zhang Y, Mutailifu A, Lan H. Structure, development, and the salt response of salt bladders in Chenopodium album L. FRONTIERS IN PLANT SCIENCE 2022; 13:989946. [PMID: 36161027 PMCID: PMC9493005 DOI: 10.3389/fpls.2022.989946] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Accepted: 08/18/2022] [Indexed: 06/16/2023]
Abstract
Salt bladders are specialized epidermal structures that halophytes use to store and excrete excess salt. However, the cell wall composition during salt bladder development is unclear, and the functions of salt bladders in a few wild plants remain unexplored. Therefore, the present study examined salt bladder development, cell wall composition, and their roles under salt stress by employing bladder-brushed and unbrushed Chenopodium album plants. We found that the bladder cell of C. album was connected to the epidermal cells through a rectangular stalk cell and developed from the shoot tip and the young leaves. The polysaccharides of salt bladder cell wall showed dynamic distribution at different stages of development. Moreover, salt bladders affected Na+ and K+ accumulation, increased reactive oxygen species scavenging, and improved the osmoregulation and photosynthetic efficiency in leaves, subsequently enhancing the salt tolerance of plants. The findings strengthen our knowledge of the physiological mechanisms of the accessory structures in desert plants, which can be used as a reference for further research at the molecular level.
Collapse
|
2
|
The Pellicle-Another Strategy of the Root Apex Protection against Mechanical Stress? Int J Mol Sci 2021; 22:ijms222312711. [PMID: 34884528 PMCID: PMC8658001 DOI: 10.3390/ijms222312711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 11/20/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022] Open
Abstract
In grasses, the apical part of the root is covered by a two-layered deposit of extracellular material, the pellicle, which together with the outer periclinal wall of protodermal cells forms the three-layered epidermal surface. In this study, the effect of mechanical stress on the pellicle was examined. An experiment was performed, in which maize roots were grown in narrow diameter plastic tubes with conical endings for 24 h. Two groups of experimental roots were included in the analysis: stressed (S) roots, whose tips did not grow out of the tubes, and recovering (R) roots, whose apices grew out of the tube. Control (C) roots grew freely between the layers of moist filter paper. Scanning electron microscopy and confocal microscopy analysis revealed microdamage in all the layers of the epidermal surface of S roots, however, protodermal cells in the meristematic zone remained viable. The outermost pellicle layer was twice as thick as in C roots. In R roots, large areas of dead cells were observed between the meristematic zone and the transition zone. The pellicle was defective with a discontinuous and irregular outermost layer. In the meristematic zone the pellicle was undamaged and the protodermal cells were intact. The results lead to the conclusion that the pellicle may prevent damage to protodermal cells, thus protecting the root apical meristem from the negative effects of mechano-stress.
Collapse
|
3
|
Palacio-López K, Tinaz B, Holzinger A, Domozych DS. Arabinogalactan Proteins and the Extracellular Matrix of Charophytes: A Sticky Business. FRONTIERS IN PLANT SCIENCE 2019; 10:447. [PMID: 31031785 PMCID: PMC6474363 DOI: 10.3389/fpls.2019.00447] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/25/2019] [Indexed: 05/20/2023]
Abstract
Charophytes represent the group of green algae whose ancestors invaded land and ultimately gave rise to land plants 450 million years ago. While Zygnematophyceae are believed to be the direct sister lineage to embryophytes, different members of this group (Penium, Spirogyra, Zygnema) and the advanced thallus forming Coleochaete as well as the sarcinoid basal streptophyte Chlorokybus were investigated concerning their vegetative extracellular matrix (ECM) properties. Many taxa exhibit adhesion phenomena that are critical for affixing to a substrate or keeping cells together in a thallus, however, there is a great variety in possible reactions to e.g., wounding. In this study an analysis of adhesion mechanisms revealed that arabinogalactan proteins (AGPs) are most likely key adhesion molecules. Through use of monoclonal antibodies (JIM13) or the Yariv reagent, AGPs were located in cell surface sheaths and cell walls that were parts of the adhesion focal zones on substrates including wound induced rhizoid formation. JIM5, detecting highly methyl-esterfied homoglacturonan and JIM8, an antibody detecting AGP glycan and LM6 detecting arabinans were also tested and a colocalization was found in several examples (e.g., Zygnema) suggesting an interplay between these components. AGPs have been described in this study to perform both, cell to cell adhesion in algae forming thalli and cell to surface adhesion in the filamentous forms. These findings enable a broader evolutionary understanding of the function of AGPs in charophyte green algae.
Collapse
Affiliation(s)
| | - Berke Tinaz
- Department of Biology, Skidmore College, Saratoga Springs, NY, United States
| | | | - David S. Domozych
- Department of Biology, Skidmore College, Saratoga Springs, NY, United States
| |
Collapse
|
4
|
Potocka I, Godel K, Dobrowolska I, Kurczyńska EU. Spatio-temporal localization of selected pectic and arabinogalactan protein epitopes and the ultrastructural characteristics of explant cells that accompany the changes in the cell fate during somatic embryogenesis in Arabidopsis thaliana. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 127:573-589. [PMID: 29727861 DOI: 10.1016/j.plaphy.2018.04.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 04/24/2018] [Accepted: 04/24/2018] [Indexed: 06/08/2023]
Abstract
During somatic embryogenesis (SE), explant cells undergo changes in the direction of their differentiation, which lead to diverse cell phenotypes. Although the genetic bases of the SE have been extensively studied in Arabidopsis thaliana, little is known about the chemical characteristics of the wall of the explant cells, which undergo changes in the direction of differentiation. Thus, we examined the occurrence of selected pectic and AGP epitopes in explant cells that display different phenotypes during SE. Explants examinations have been supplemented with an analysis of the ultrastructure. The deposition of selected pectic and AGP epitopes in somatic embryos was determined. Compared to an explant at the initial stage, a/embryogenic/totipotent and meristematic/pluripotent cells were characterized by a decrease in the presence of AGP epitopes, b/the presence of AGP epitopes in differentiated cells was similar, and c/an increase of analyzed epitopes was detected in the callus cells. Totipotent cells could be distinguished from pluripotent cells by: 1/the presence of the LM2 epitope in the latest one, 2/the appearance of the JIM16 epitope in totipotent cells, and 3/the more abundant presence of the JIM7 epitope in the totipotent cells. The LM5 epitope characterized the wall of the cells that were localized within the mass of embryogenic domain. The JIM8, JIM13 and JIM16 AGP epitopes appeared to be the most specific for the callus cells. The results indicate a relationship between the developmental state of the explant cells and the chemical composition of the cell walls.
Collapse
Affiliation(s)
- Izabela Potocka
- Department of Cell Biology, Faculty of Biology and Environmental Protection, University of Silesia, Jagiellońska 28, 40-032, Katowice, Poland
| | - Kamila Godel
- Department of Cell Biology, Faculty of Biology and Environmental Protection, University of Silesia, Jagiellońska 28, 40-032, Katowice, Poland
| | - Izabela Dobrowolska
- Department of Cell Biology, Faculty of Biology and Environmental Protection, University of Silesia, Jagiellońska 28, 40-032, Katowice, Poland
| | - Ewa U Kurczyńska
- Department of Cell Biology, Faculty of Biology and Environmental Protection, University of Silesia, Jagiellońska 28, 40-032, Katowice, Poland.
| |
Collapse
|
5
|
Integrating cell biology and proteomic approaches in plants. J Proteomics 2017; 169:165-175. [DOI: 10.1016/j.jprot.2017.04.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/29/2017] [Accepted: 04/18/2017] [Indexed: 11/22/2022]
|
6
|
Sun Q, Sun Y, Juzenas K. Immunogold scanning electron microscopy can reveal the polysaccharide architecture of xylem cell walls. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:2231-2244. [PMID: 28398585 PMCID: PMC5447876 DOI: 10.1093/jxb/erx103] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Immunofluorescence microscopy (IFM) and immunogold transmission electron microscopy (TEM) are the two main techniques commonly used to detect polysaccharides in plant cell walls. Both are important in localizing cell wall polysaccharides, but both have major limitations, such as low resolution in IFM and restricted sample size for immunogold TEM. In this study, we have developed a robust technique that combines immunocytochemistry with scanning electron microscopy (SEM) to study cell wall polysaccharide architecture in xylem cells at high resolution over large areas of sample. Using multiple cell wall monoclonal antibodies (mAbs), this immunogold SEM technique reliably localized groups of hemicellulosic and pectic polysaccharides in the cell walls of five different xylem structures (vessel elements, fibers, axial and ray parenchyma cells, and tyloses). This demonstrates its important advantages over the other two methods for studying cell wall polysaccharide composition and distribution in these structures. In addition, it can show the three-dimensional distribution of a polysaccharide group in the vessel lateral wall and the polysaccharide components in the cell wall of developing tyloses. This technique, therefore, should be valuable for understanding the cell wall polysaccharide composition, architecture and functions of diverse cell types.
Collapse
Affiliation(s)
- Qiang Sun
- Department of Biology, University of Wisconsin, Stevens Point, WI 54481, USA
| | - Yuliang Sun
- School of Medicine, Boston University, Boston, MA 02118, USA
| | - Kevin Juzenas
- Department of Biology, University of Wisconsin, Stevens Point, WI 54481, USA
| |
Collapse
|
7
|
Wu Y, Fan W, Li X, Chen H, Takáč T, Šamajová O, Fabrice MR, Xie L, Ma J, Šamaj J, Xu C. Expression and distribution of extensins and AGPs in susceptible and resistant banana cultivars in response to wounding and Fusarium oxysporum. Sci Rep 2017; 7:42400. [PMID: 28218299 PMCID: PMC5316987 DOI: 10.1038/srep42400] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 01/09/2017] [Indexed: 01/10/2023] Open
Abstract
Banana Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc) is soil-borne disease of banana (Musa spp.) causing significant economic losses. Extensins and arabinogalactan proteins (AGPs) are cell wall components important for pathogen defence. Their significance for Foc resistance in banana was not reported so far. In this study, two banana cultivars differing in Foc sensitivity were used to monitor the changes in transcript levels, abundance and distribution of extensins and AGPs after wounding and Foc inoculation. Extensins mainly appeared in the root cap and meristematic cells. AGPs recognized by JIM13, JIM8, PN16.4B4 and CCRC-M134 antibodies located in root hairs, xylem and root cap. Individual AGPs and extensins showed specific radial distribution in banana roots. At the transcript level, seven extensins and 23 AGPs were differentially expressed between two banana cultivars before and after treatments. Two extensins and five AGPs responded to the treatments at the protein level. Most extensins and AGPs were up-regulated by wounding and pathogen inoculation of intact plants but down-regulated by pathogen attack of wounded plants. Main components responsible for the resistance of banana were MaELP-2 and MaPELP-2. Our data revealed that AGPs and extensins represent dynamic cell wall components involved in wounding and Foc resistance.
Collapse
Affiliation(s)
- Yunli Wu
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Wei Fan
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Xiaoquan Li
- Institute of Biotechnology, Guangxi Academy of Agricultural Sciences, Nanning 530007, China
| | - Houbin Chen
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Tomáš Takáč
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Olga Šamajová
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | | | - Ling Xie
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Juan Ma
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Jozef Šamaj
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Chunxiang Xu
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| |
Collapse
|
8
|
Wang H, Lan P, Shen RF. Integration of transcriptomic and proteomic analysis towards understanding the systems biology of root hairs. Proteomics 2016; 16:877-93. [PMID: 26749523 DOI: 10.1002/pmic.201500265] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 12/28/2015] [Accepted: 01/05/2016] [Indexed: 11/11/2022]
Abstract
Plants and other multicellular organisms consist of many types of specialized cells. Systems-wide exploration of large-scale information from singe cell level is essential to understand how cell works. Root hairs, tubular-shaped outgrowths from root epidermal cells, play important roles in the acquisition of nutrients and water, in the interaction with microbe, and in plant anchorage, and represent an ideal model to study the biology of a single cell type. Single cell sampling combined with omics approaches has been applied to study plant root hairs. This review emphasizes the integration of omics approaches towards understanding the systems biology of root hairs, unraveling the common and plant species-specific properties of root hairs, as well as the concordance of protein and transcript abundance. Understanding plant root hair biology by mining the integrated omics data will provide a way to know how a single cell differentiates, elongates, and functions, which might help molecularly modify crops for developing sustainable agriculture practices.
Collapse
Affiliation(s)
- Han Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, P. R. China
| | - Ping Lan
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, P. R. China
| | - Ren Fang Shen
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, P. R. China
| |
Collapse
|
9
|
Betekhtin A, Rojek M, Milewska-Hendel A, Gawecki R, Karcz J, Kurczynska E, Hasterok R. Spatial Distribution of Selected Chemical Cell Wall Components in the Embryogenic Callus of Brachypodium distachyon. PLoS One 2016; 11:e0167426. [PMID: 27893856 PMCID: PMC5125709 DOI: 10.1371/journal.pone.0167426] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Accepted: 11/14/2016] [Indexed: 02/06/2023] Open
Abstract
Brachypodium distachyon L. Beauv. (Brachypodium) is a species that has become an excellent model system for gaining a better understanding of various areas of grass biology and improving plant breeding. Although there are some studies of an in vitro Brachypodium culture including somatic embryogenesis, detailed knowledge of the composition of the main cell wall components in the embryogenic callus in this species is missing. Therefore, using the immunocytochemical approach, we targeted 17 different antigens of which five were against the arabinogalactan proteins (AGP), three were against extensins, six recognised pectic epitopes and two recognised hemicelluloses. These studies were complemented by histological and scanning electron microscopy (SEM) analyses. We revealed that the characteristic cell wall components of Brachypodium embryogenic calli are AGP epitopes that are recognised by the JIM16 and LM2 antibodies, an extensin epitope that is recognised by the JIM11 antibody and a pectic epitopes that is recognised by the LM6 antibody. Furthermore, we demonstrated that AGPs and pectins are the components of the extracellular matrix network in Brachypodium embryogenic culture. Additionally, SEM analysis demonstrated the presence of an extracellular matrix on the surface of the calli cells. In conclusion, the chemical compositions of the cell walls and ECMSN of Brachypodium callus show spatial differences that correlate with the embryogenic character of the cells. Thus, the distribution of pectins, AGPs and hemicelluloses can be used as molecular markers of embryogenic cells. The presented data extends the knowledge about the chemical composition of the embryogenic callus cells of Brachypodium.
Collapse
Affiliation(s)
- Alexander Betekhtin
- Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Magdalena Rojek
- Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Anna Milewska-Hendel
- Department of Cell Biology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Robert Gawecki
- Department of Cell Biology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Jagna Karcz
- Scanning Electron Microscopy Laboratory, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Ewa Kurczynska
- Department of Cell Biology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Robert Hasterok
- Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| |
Collapse
|
10
|
Yan Y, Takáč T, Li X, Chen H, Wang Y, Xu E, Xie L, Su Z, Šamaj J, Xu C. Variable content and distribution of arabinogalactan proteins in banana (Musa spp.) under low temperature stress. FRONTIERS IN PLANT SCIENCE 2015; 6:353. [PMID: 26074928 PMCID: PMC4444754 DOI: 10.3389/fpls.2015.00353] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 05/04/2015] [Indexed: 05/25/2023]
Abstract
Information on the spatial distribution of arabinogalactan proteins (AGPs) in plant organs and tissues during plant reactions to low temperature (LT) is limited. In this study, the extracellular distribution of AGPs in banana leaves and roots, and their changes under LT stress were investigated in two genotypes differing in chilling tolerance, by immuno-techniques using 17 monoclonal antibodies against different AGP epitopes. Changes in total classical AGPs in banana leaves were also tested. The results showed that AGP epitopes recognized by JIM4, JIM14, JIM16, and CCRC-M32 antibodies were primarily distributed in leaf veins, while those recognized by JIM8, JIM13, JIM15, and PN16.4B4 antibodies exhibited predominant sclerenchymal localization. Epitopes recognized by LM2, LM14, and MAC207 antibodies were distributed in both epidermal and mesophyll cells. Both genotypes accumulated classical AGPs in leaves under LT treatment, and the chilling tolerant genotype contained higher classical AGPs at each temperature treatment. The abundance of JIM4 and JIM16 epitopes in the chilling-sensitive genotype decreased slightly after LT treatment, and this trend was opposite for the tolerant one. LT induced accumulation of LM2- and LM14-immunoreactive AGPs in the tolerant genotype compared to the sensitive one, especially in phloem and mesophyll cells. These epitopes thus might play important roles in banana LT tolerance. Different AGP components also showed differential distribution patterns in banana roots. In general, banana roots started to accumulate AGPs under LT treatment earlier than leaves. The levels of AGPs recognized by MAC207 and JIM13 antibodies in the control roots of the tolerant genotype were higher than in the chilling sensitive one. Furthermore, the chilling tolerant genotype showed high immuno-reactivity against JIM13 antibody. These results indicate that several AGPs are likely involved in banana tolerance to chilling injury.
Collapse
Affiliation(s)
- Yonglian Yan
- Department of Pomology, College of Horticulture, South China Agricultural UniversityGuangzhou, China
| | - Tomáš Takáč
- Department of Cell Biology, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
| | - Xiaoquan Li
- Department of Healthy Seeds, Institute of Biotechnology, Guangxi Academy of Agricultural SciencesNanning, China
| | - Houbin Chen
- Department of Pomology, College of Horticulture, South China Agricultural UniversityGuangzhou, China
| | - Yingying Wang
- Department of Pomology, College of Horticulture, South China Agricultural UniversityGuangzhou, China
| | - Enfeng Xu
- Department of Pomology, College of Horticulture, South China Agricultural UniversityGuangzhou, China
| | - Ling Xie
- Department of Pomology, College of Horticulture, South China Agricultural UniversityGuangzhou, China
| | - Zhaohua Su
- Department of Pomology, College of Horticulture, South China Agricultural UniversityGuangzhou, China
| | - Jozef Šamaj
- Department of Cell Biology, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
| | - Chunxiang Xu
- Department of Pomology, College of Horticulture, South China Agricultural UniversityGuangzhou, China
| |
Collapse
|
11
|
Lopez RA, Renzaglia KS. Multiflagellated sperm cells of Ceratopteris richardii are bathed in arabinogalactan proteins throughout development. AMERICAN JOURNAL OF BOTANY 2014; 101:2052-2061. [PMID: 25480702 DOI: 10.3732/ajb.1400424] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
UNLABELLED • PREMISE OF THE STUDY Sperm cell differentiation in ferns involves the origin of an elaborate locomotory apparatus, including 70+ flagella, and the structural modification of every cellular component. Because arabinogalactan proteins (AGPs) are implicated in molecular signaling and in regulation of plant development, we speculated that these glycoproteins would be present during spermiogenesis in ferns.• METHODS Using β-glucosyl Yariv reagents that specifically bind to and inhibit AGPs and immunogold localizations with monoclonal antibodies JIM13, JIM8, and LM6, we examined the specific expression patterns of AGPs and inhibited their function during sperm cell development in the model fern Ceratopteris richardii.• KEY RESULTS Developing sperm cells stained intensely with Yariv phenylglycosides, demonstrating the presence of AGPs. JIM13-AGP epitopes were widespread throughout development in the expanding extraprotoplasmic matrix (EPM) in which flagella elongate, cytoplasm is eliminated, and spherical spermatids become coiled. JIM8 and LM6 epitopes localized to the plasmalemma on growing flagella and on the rapidly changing sperm cell body. Spermatids treated with β-glucosyl lacked an EPM and formed fewer, randomly arranged flagella.• CONCLUSIONS We demonstrated that AGPs are abundant in the EPM and along the plasmalemma and that the three AGP epitopes have specific expression patterns during development. Coupled with inhibition studies, these results identify AGPs as critical to the formation of an extraprotoplasmic matrix and the consequent origin and development of flagella in an orderly and precise fashion around the cell. We speculate that AGPs may play additional roles as signaling molecules involved in cell shaping, cytoskeletal development, vesicle trafficking, and cytoplasmic elimination.
Collapse
Affiliation(s)
- Renee A Lopez
- Department of Plant Biology, Southern Illinois University Carbondale, Carbondale, Illinois 62901 USA
| | - Karen S Renzaglia
- Department of Plant Biology, Southern Illinois University Carbondale, Carbondale, Illinois 62901 USA
| |
Collapse
|
12
|
Liu W, Li C, Zhang Q, Lei Z, Hou Y, Dai F, Lu C. Sample preparation to observe the straight and flat posture of silkworm embryo under scanning electron microscopy via glycerol substitution method. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2014; 20:964-967. [PMID: 24559610 DOI: 10.1017/s1431927614000233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the preparation process for scanning electron microscopy (SEM), flexed silkworm embryos typically assume several curled shapes with irregular postures that obscure morphological details during SEM observation. We describe a preparation technique based on glycerol substitution for better SEM visualization of straight and flat silkworm embryos. Glycerol has high viscosity, low vapor pressure, and sufficient electrical conductivity. Silkworm embryos were infiltrated with glycerol and arranged in a straight posture or flattened using a cover slip. Samples were directly observed by SEM without additional dehydration, drying, or coating procedures. The complete ventral side could be easily viewed in one image. Recoating alleviated the charging phenomenon. This represents a simple method for preparation of straight and flat samples from curled biological specimens for SEM observation.
Collapse
Affiliation(s)
- Wenbin Liu
- 1Department of Pharmaceutical and Biological Engineering,School of Chemical Engineering,Sichuan University,Chengdu 610065,China
| | - Chenzhao Li
- 1Department of Pharmaceutical and Biological Engineering,School of Chemical Engineering,Sichuan University,Chengdu 610065,China
| | - Qi Zhang
- 1Department of Pharmaceutical and Biological Engineering,School of Chemical Engineering,Sichuan University,Chengdu 610065,China
| | - Zhixin Lei
- 1Department of Pharmaceutical and Biological Engineering,School of Chemical Engineering,Sichuan University,Chengdu 610065,China
| | - Yanqi Hou
- 1Department of Pharmaceutical and Biological Engineering,School of Chemical Engineering,Sichuan University,Chengdu 610065,China
| | - Fangyin Dai
- 2State Key Laboratory of Silkworm Genome Biology,Southwest University,Chongqing 400716,China
| | - Cheng Lu
- 2State Key Laboratory of Silkworm Genome Biology,Southwest University,Chongqing 400716,China
| |
Collapse
|
13
|
Developmental localization and methylesterification of pectin epitopes during somatic embryogenesis of banana (Musa spp. AAA). PLoS One 2011; 6:e22992. [PMID: 21826225 PMCID: PMC3149637 DOI: 10.1371/journal.pone.0022992] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Accepted: 07/11/2011] [Indexed: 01/25/2023] Open
Abstract
Background The plant cell walls play an important role in somatic embryogenesis and plant development. Pectins are major chemical components of primary cell walls while homogalacturonan (HG) is the most abundant pectin polysaccharide. Developmental regulation of HG methyl-esterification degree is important for cell adhesion, division and expansion, and in general for proper organ and plant development. Methodology/Principal Findings Developmental localization of pectic homogalacturonan (HG) epitopes and the (1→4)-β-D-galactan epitope of rhamnogalacturonan I (RG-I) and degree of pectin methyl-esterification (DM) were studied during somatic embryogenesis of banana (Musa spp. AAA). Histological analysis documented all major developmental stages including embryogenic cells (ECs), pre-globular, globular, pear-shaped and cotyledonary somatic embryos. Histochemical staining of extracellularly secreted pectins with ruthenium red showed the most intense staining at the surface of pre-globular, globular and pear-shaped somatic embryos. Biochemical analysis revealed developmental regulation of galacturonic acid content and DM in diverse embryogenic stages. Immunodots and immunolabeling on tissue sections revealed developmental regulation of highly methyl-esterified HG epitopes recognized by JIM7 and LM20 antibodies during somatic embryogenesis. Cell walls of pre-globular/globular and late-stage embryos contained both low methyl-esterified HG epitopes as well as partially and highly methyl-esterified ones. Extracellular matrix which covered surface of early developing embryos contained pectin epitopes recognized by 2F4, LM18, JIM5, JIM7 and LM5 antibodies. De-esterification of cell wall pectins by NaOH caused a decrease or an elimination of immunolabeling in the case of highly methyl-esterified HG epitopes. However, immunolabeling of some low methyl-esterified epitopes appeared stronger after this base treatment. Conclusions/Significance These data suggest that both low- and highly-methyl-esterified HG epitopes are developmentally regulated in diverse embryogenic stages during somatic embryogenesis. This study provides new information about pectin composition, HG methyl-esterification and developmental localization of pectin epitopes during somatic embryogenesis of banana.
Collapse
|
14
|
Pan X, Yang X, Lin G, Zou R, Chen H, Samaj J, Xu C. Ultrastructural changes and the distribution of arabinogalactan proteins during somatic embryogenesis of banana (Musa spp. AAA cv. 'Yueyoukang 1'). PHYSIOLOGIA PLANTARUM 2011; 142:372-89. [PMID: 21496030 DOI: 10.1111/j.1399-3054.2011.01478.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A better understanding of somatic embryogenesis in banana (Musa spp.) may provide a practical way to improve regeneration of banana plants. In this study, we applied scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to visualize the ultrastructural changes during somatic embryogenesis of banana (Musa AAA cv. 'Yueyoukang 1'). We also used histological and immunohistochemical techniques with 16 monoclonal antibodies to study the spatial distribution and cellular/subcellular localization of different arabinogalactan protein (AGP) components of the cell wall during somatic embryogenesis. Histological study with periodic acid-Schiff staining documented diverse embryogenic stages from embryogenic cells (ECs) to the late embryos. SEM revealed a mesh-like structure on the surface of proembryos which represented an early structural marker of somatic embryogenesis. TEM showed that ECs were rich in juvenile mitochondria, endoplasmic reticulum and Golgi stacks. Cells in proembryos and early globular embryos resembled ECs, but they were more vacuolated, showed more regular nuclei and slightly more developed organelles. Immunocytochemical study revealed that the signal of most AGP epitopes was stronger in starch-rich cells when compared with typical ECs. The main AGP component in the extracellular matrix surface network of banana proembryos was the MAC204 epitope. Later, AGP immunolabelling patterns varied with the developmental stages of the embryos. These results about developmental regulation of AGP epitopes along with developmental changes in the ultrastructure of cells are providing new insights into the somatic embryogenesis of banana.
Collapse
Affiliation(s)
- Xiao Pan
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | | | | | | | | | | | | |
Collapse
|
15
|
Xu C, Takáč T, Burbach C, Menzel D, Šamaj J. Developmental localization and the role of hydroxyproline rich glycoproteins during somatic embryogenesis of banana (Musa spp. AAA). BMC PLANT BIOLOGY 2011; 11:38. [PMID: 21349190 PMCID: PMC3048498 DOI: 10.1186/1471-2229-11-38] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Accepted: 02/24/2011] [Indexed: 05/07/2023]
Abstract
BACKGROUND Hydroxyproline rich glycoproteins (HRGPs) are implicated to have a role in many aspects of plant growth and development but there is limited knowledge about their localization and function during somatic embryogenesis of higher plants. In this study, the localization and function of hydroxyproline rich glycoproteins in embryogenic cells (ECs) and somatic embryos of banana were investigated by using immunobloting and immunocytochemistry with monoclonal JIM11 and JIM20 antibodies as well as by treatment with 3,4-dehydro-L-proline (3,4-DHP, an inhibitor of extensin biosynthesis), and by immunomodulation with the JIM11 antibody. RESULTS Immunofluorescence labelling of JIM11 and JIM20 hydroxyproline rich glycoprotein epitopes was relatively weak in non-embryogenic cells (NECs), mainly on the edge of small cell aggregates. On the other hand, hydroxyproline rich glycoprotein epitopes were found to be enriched in early embryogenic cells as well as in various developmental stages of somatic embryos. Embryogenic cells (ECs), proembryos and globular embryos showed strong labelling of hydroxyproline rich glycoprotein epitopes, especially in their cell walls and outer surface layer, so-called extracellular matrix (ECM). This hydroxyproline rich glycoprotein signal at embryo surfaces decreased and/or fully disappeared during later developmental stages (e.g. pear-shaped and cotyledonary stages) of embryos. In these later developmental embryogenic stages, however, new prominent hydroxyproline rich glycoprotein labelling appeared in tri-cellular junctions among parenchymatic cells inside these embryos. Overall immunofluorescence labelling of late stage embryos with JIM20 antibody was weaker than that of JIM11. Western blot analysis supported the above immunolocalization data. The treatment with 3,4-DHP inhibited the development of embryogenic cells and decreased the rate of embryo germination. Embryo-like structures, which developed after 3,4-DHP treatment showed aberrant non-compact epidermis with discontinuous ECM at the outer surface as well as much less immunolabelling with the JIM11 antibody. This treatment also decreased the plant regeneration capacity in embryogenic banana cultures. Finally, immunomodulation of surface hydroxyproline rich glycoproteins by co-culture of embryos with the JIM11 antibody resulted in a much lower germination capacity of these embryos. CONCLUSIONS These results suggest that hydroxyproline rich glycoproteins play an important developmental role, especially in the process of regeneration and germination of embryos during plant regeneration via somatic embryogenesis. Proper content and localization of hydroxyproline rich glycoproteins seem to be essential for the formation and regeneration of banana somatic embryos.
Collapse
Affiliation(s)
- Chunxiang Xu
- College of Horticulture, South China Agricultural University, Guangzhou, 510642 Guangdong, PR China
| | - Tomáš Takáč
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Cell Biology, Faculty of Science, Palacký University, 783 71 Olomouc, Czech Republic
| | - Christian Burbach
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115 Bonn, Germany
| | - Diedrik Menzel
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115 Bonn, Germany
| | - Jozef Šamaj
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Cell Biology, Faculty of Science, Palacký University, 783 71 Olomouc, Czech Republic
| |
Collapse
|
16
|
Popielarska-Konieczna M, Bohdanowicz J, Starnawska E. Extracellular matrix of plant callus tissue visualized by ESEM and SEM. PROTOPLASMA 2010; 247:121-125. [PMID: 20424873 DOI: 10.1007/s00709-010-0149-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Accepted: 04/12/2010] [Indexed: 05/29/2023]
Abstract
Actinidia deliciosa endosperm-derived callus culture is stable over a long period of culture. This system was used to investigate the ultrastructure of extracellular matrix occurring in morphogenic tissue. Specimens were prepared by different biological techniques (chemical fixation, liquid nitrogen fixation, glycerol substitution, critical-point drying, lyophilization) and observed by scanning electron microscopy (SEM). Fresh and wet samples were analyzed with the use of environmental scanning electron microscopy (ESEM). Extracellular matrix was observed on the surface of cell clusters as a membranous layer or reticulated network, shrunken or wrinkled, depending on the procedure. Generally, shrunken membranous layers with a globular appearance and fibrils were noted after critical-point drying and liquid nitrogen fixation. Smoother surface layers without visible fibrils and showing porosity were typically seen by environmental scanning electron microscopy. Preservation with glycerol substitution caused wrinkled appearance of examined layer. Analysis of fresh samples yielded images closer to their natural state than did critical-point drying or fixation in liquid nitrogen, but it seems best to compare the results of different visualization methods. This is the first report of ESEM observations of plant extracellular matrix and comparison with SEM images from fixed material.
Collapse
|
17
|
Kwasniewski M, Janiak A, Mueller-Roeber B, Szarejko I. Global analysis of the root hair morphogenesis transcriptome reveals new candidate genes involved in root hair formation in barley. JOURNAL OF PLANT PHYSIOLOGY 2010; 167:1076-1083. [PMID: 20388575 DOI: 10.1016/j.jplph.2010.02.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Revised: 02/17/2010] [Accepted: 02/18/2010] [Indexed: 05/29/2023]
Abstract
Root hairs are long tubular outgrowths of specialized root epidermal cells that play an important role in plant nutrition and water uptake. They are also an important model in studies of higher plant cell differentiation. In contrast to the model dicot Arabidopsis thaliana, currently very little is known about the genetic and molecular basis of root hair formation in monocots, including major cereals. To elucidate candidate genes controlling this developmental process in barley, we took advantage of the recently established Affymetrix GeneChip Barley1 Genome Array to carry out global transcriptome analyses of hairless and root hair primordia-forming roots of two barely mutant lines. Expression profiling of the root-hairless mutant rhl1.a and its wild type parent variety 'Karat' revealed 10 genes potentially involved in the early step of root hair formation in barley. Differential expression of all identified genes was confirmed by quantitative reverse transcription-polymerase chain reaction. The genes identified encode proteins associated with the cell wall and membranes, including one gene for xyloglucan endotransglycosylase, three for peroxidase enzymes and five for arabinogalactan protein, extensin, leucine-rich-repeat protein, phosphatidylinositol phosphatidylcholine transfer protein and a RhoGTPase GDP dissociation inhibitor, respectively. The molecular function of one gene is unknown at present. The expression levels of these genes were strongly reduced in roots of the root-hairless mutant rhl1.a compared to the parent variety, while expression of all 10 genes was similar in another mutant, i.e. rhp1.b, that has lost its ability to develop full root hairs but still forms hairs blocked at the primordium stage, and its wild type relative. This clearly indicates that the new genes identified are involved in the initiation of root hair morphogenesis in barley.
Collapse
Affiliation(s)
- Miroslaw Kwasniewski
- Department of Genetics, University of Silesia, Jagiellonska 28, 40-032 Katowice, Poland.
| | | | | | | |
Collapse
|
18
|
Ma W, Muthreich N, Liao C, Franz-Wachtel M, Schütz W, Zhang F, Hochholdinger F, Li C. The Mucilage Proteome of Maize (Zea mays L.) Primary Roots. J Proteome Res 2010; 9:2968-76. [DOI: 10.1021/pr901168v] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Wei Ma
- Department of Plant Nutrition, China Agricultural University, Beijing 100193, PR China, Center for Plant Molecular Biology, Department of General Genetics, Eberhard Karls University Tuebingen, 72076 Tuebingen, Germany, and Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, 72076 Tuebingen, Germany
| | - Nils Muthreich
- Department of Plant Nutrition, China Agricultural University, Beijing 100193, PR China, Center for Plant Molecular Biology, Department of General Genetics, Eberhard Karls University Tuebingen, 72076 Tuebingen, Germany, and Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, 72076 Tuebingen, Germany
| | - Chengsong Liao
- Department of Plant Nutrition, China Agricultural University, Beijing 100193, PR China, Center for Plant Molecular Biology, Department of General Genetics, Eberhard Karls University Tuebingen, 72076 Tuebingen, Germany, and Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, 72076 Tuebingen, Germany
| | - Mirita Franz-Wachtel
- Department of Plant Nutrition, China Agricultural University, Beijing 100193, PR China, Center for Plant Molecular Biology, Department of General Genetics, Eberhard Karls University Tuebingen, 72076 Tuebingen, Germany, and Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, 72076 Tuebingen, Germany
| | - Wolfgang Schütz
- Department of Plant Nutrition, China Agricultural University, Beijing 100193, PR China, Center for Plant Molecular Biology, Department of General Genetics, Eberhard Karls University Tuebingen, 72076 Tuebingen, Germany, and Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, 72076 Tuebingen, Germany
| | - Fusuo Zhang
- Department of Plant Nutrition, China Agricultural University, Beijing 100193, PR China, Center for Plant Molecular Biology, Department of General Genetics, Eberhard Karls University Tuebingen, 72076 Tuebingen, Germany, and Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, 72076 Tuebingen, Germany
| | - Frank Hochholdinger
- Department of Plant Nutrition, China Agricultural University, Beijing 100193, PR China, Center for Plant Molecular Biology, Department of General Genetics, Eberhard Karls University Tuebingen, 72076 Tuebingen, Germany, and Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, 72076 Tuebingen, Germany
| | - Chunjian Li
- Department of Plant Nutrition, China Agricultural University, Beijing 100193, PR China, Center for Plant Molecular Biology, Department of General Genetics, Eberhard Karls University Tuebingen, 72076 Tuebingen, Germany, and Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, 72076 Tuebingen, Germany
| |
Collapse
|
19
|
Popielarska-Konieczna M, Kozieradzka-Kiszkurno M, Swierczyńska J, Góralski G, Slesak H, Bohdanowicz J. Ultrastructure and histochemical analysis of extracellular matrix surface network in kiwifruit endosperm-derived callus culture. PLANT CELL REPORTS 2008; 27:1137-45. [PMID: 18340450 DOI: 10.1007/s00299-008-0534-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Accepted: 02/29/2008] [Indexed: 05/10/2023]
Abstract
The study used Actinidia deliciosa endosperm-derived callus to investigate aspects of the morphology, histology and chemistry of extracellular matrix (ECM) structures in morphogenically stable tissue from long-term culture. SEM showed ECM as a membranous layer or reticulated fibrillar and granular structure linking the peripheral cells of callus domains. TEM confirmed that ECM is a distinct heterogeneous layer, up to 4 mum thick and consisting of amorphous dark-staining material, osmiophilic granules and reticulated fibres present outside the outer callus cell wall. ECM covered the surface of cells forming morphogenic domains and was reduced during organ growth. This structure may be linked to acquisition of morphogenic competence and thus may serve as a structural marker of it in endosperm-derived callus. ECM was also observed on senescent cells in contact with the morphogenic area. Treatment of living calluses with chloroform and washing with ether-methanol led to partial destruction of the extracellular layer. Digestion with pectinase removed the membranous layer almost completely and exposed thick fibrillar strands and granular remnants. Digestion with protease did not visibly affect the surface layer. Indirect immunofluorescence showed low-methylesterified pectic epitopes labelled by JIM5 monoclonal antibody. Immunolabelling, histochemistry, and solvent and enzyme treatments suggested pectins and lipids as components of the surface layer. These compounds may indicate protective, water retention and/or cell communication functions for this external layer.
Collapse
Affiliation(s)
- M Popielarska-Konieczna
- Department of Plant Cytology and Embryology, Jagiellonian University, 52 Grodzka St., 31-044 Cracow, Poland.
| | | | | | | | | | | |
Collapse
|
20
|
Samaj J, Salaj T, Matúsová R, Salaj J, Takác T, Samajová O, Volkmann D. Arabinogalactan-protein epitope Gal4 is differentially regulated and localized in cell lines of hybrid fir (Abies alba x Abies cephalonica) with different embryogenic and regeneration potential. PLANT CELL REPORTS 2008; 27:221-9. [PMID: 17943290 DOI: 10.1007/s00299-007-0429-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Revised: 07/03/2007] [Accepted: 07/23/2007] [Indexed: 05/19/2023]
Abstract
Arabinogalactan proteins (AGPs) are important proteoglycans regulating somatic embryogenesis in diverse plant species. Embryogenic cells of somatic embryos are covered by special extracellular cell wall layer called extracellular surface matrix network (ECMSN) at their early developmental stages. Here we show that highly embryogenic cell line AC78 of hybrid fir (Abies alba x Abies cephalonica) differs from very low-embryogenic cell line AC77 in the abundance, subcellular localization and deposition of subset of secreted AGPs. A specific AGP epitope containing Gal residues and reacting to Gal4 antibody is secreted and deposited into ECMSN, which covers the surface of the embryogenic cells showing high embryogenic and regeneration capacity in the cell line AC78. On the other hand, this Gal4 AGP epitope was not secreted and/or found on the surface of meristematic cells showing low embryogenic and regeneration capacity in the cell line AC77, as well as on the surface of non-embryogenic suspensor cells and callus cells in both cell lines AC77 and AC78. As a positive control, we have used another AGP epitope LM2 (containing glucuronic acid) showing no significant differences in these two Abies hybrid lines. This study defines specific AGPs containing beta-(1-->6)-galactotetraosyl group as a first molecular component of ECMSN covering embryogenic cells in gymnosperms.
Collapse
Affiliation(s)
- Jozef Samaj
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115 Bonn, Germany.
| | | | | | | | | | | | | |
Collapse
|
21
|
Wojtaszek P, Baluska F, Kasprowicz A, Luczak M, Volkmann D. Domain-specific mechanosensory transmission of osmotic and enzymatic cell wall disturbances to the actin cytoskeleton. PROTOPLASMA 2007; 230:217-30. [PMID: 17458636 DOI: 10.1007/s00709-006-0235-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2006] [Accepted: 05/18/2006] [Indexed: 05/15/2023]
Abstract
Plant protoplasts are embedded within surrounding cell walls and the cell wall-plasma membrane-cytoskeleton (WMC) structural continuum seems to be crucial for the proper functioning of plant cells. We have utilised the protoplast preparation methodology to study the organisation and the putative components of the WMC continuum. Application of an osmotic agent evoked plasmolysis of the Zea mays root apex cells which appeared to be cell type- and growth stage-specific. Simultaneous use of wall polysaccharide-digesting enzymes selectively severed linkages between the components of the WMC continuum which changed the plasmolytic patterns in various cell types. This was followed by a reorganisation of filamentous actin aimed to reinforce protoplast boundaries and maintain the functioning of intercellular contact sites, especially at the cross walls. Particularly strong effects were evoked by pectin-degrading enzymes. Such treatments demonstrated directly the differentiated composition of various wall domains surrounding individual cells with the pectin-enriched cross walls (synapses), and the cellulose-hemicellulose network dominating the side walls. The same wall-degrading enzymes were used for in vitro digestion of isolated Lupinus albus cell walls followed by the extraction of wall proteins. Selective release of proteins suggested the importance of wall polysaccharide-protein interactions in the maintenance of the functioning and mechanical stability of root cell walls.
Collapse
Affiliation(s)
- Przemysław Wojtaszek
- Institute of Cellular and Molecular Botany, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany.
| | | | | | | | | |
Collapse
|
22
|
Namasivayam P, Skepper J, Hanke D. Identification of a potential structural marker for embryogenic competency in the Brassica napus spp. oleifera embryogenic tissue. PLANT CELL REPORTS 2006; 25:887-95. [PMID: 16568254 DOI: 10.1007/s00299-006-0122-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2005] [Revised: 11/18/2005] [Accepted: 01/14/2006] [Indexed: 05/08/2023]
Abstract
The Brassica napus secondary embryogenesis system requires no exogenous growth regulator to stimulate embryo development. It is stable embryogenically over a long period of culture and has a distinct pre-embryogenic stage. This system was used to investigate the morphological and cellular changes occurring in the embryogenic tissue compared to non-embryogenic tissue using various microscopy techniques. A unique ultrastructural feature designated the extracellular matrix (ECM) was observed on the surface of pre-embryogenic embryoids but not on the non-embryogenic individuals. The ECM layer was found to be dominant in the pre-embryogenic stage and reduced to fragments during embryo growth and development in mature embryogenic tissue. This is a novel aspect of the phenotype previously unreported in the Brassica system. This structure might be linked to acquisition of embryogenic competence.
Collapse
Affiliation(s)
- Parameswari Namasivayam
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | | | | |
Collapse
|
23
|
Samaj J, Baluska F, Pretová A, Volkmann D. Auxin deprivation induces a developmental switch in maize somatic embryogenesis involving redistribution of microtubules and actin filaments from endoplasmic to cortical cytoskeletal arrays. PLANT CELL REPORTS 2003; 21:940-5. [PMID: 12835902 DOI: 10.1007/s00299-003-0611-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2002] [Revised: 02/06/2003] [Accepted: 02/10/2003] [Indexed: 05/22/2023]
Abstract
A developmental switch from non-polar pre-embryogenic units to polarized transition units in maize embryogenic callus is caused by auxin deprivation from the culture medium. This switch is accompanied by cytoskeletal rearrangements in embryogenic cells. An immunofluorescence study revealed prominent endoplasmic microtubules and actin filament meshworks radiating from the nuclear surfaces in pre-embryogenic cells growing on medium supplemented with auxin. On the other hand, parallel-organized cortical microtubules and cortical actin filament networks are inherently associated with polarized embryogenic cells of transition units growing on medium without auxin. These results indicate that fine-tuning of the dynamic equilibrium between endoplasmic and cortical cytoskeletal arrays is important for progress in somatic embryogenesis.
Collapse
Affiliation(s)
- J Samaj
- Institute of Plant Genetics and Biotechnology, Slovak Academy of Sciences, Akademická 2, 95007 Nitra, Slovakia.
| | | | | | | |
Collapse
|
24
|
Passarinho PA, de Vries SC. ArabidopsisChitinases: a Genomic Survey. THE ARABIDOPSIS BOOK 2002; 1:e0023. [PMID: 22303199 PMCID: PMC3243303 DOI: 10.1199/tab.0023] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Plant chitinases (EC 3.2.1.14) belong to relatively large gene families subdivided in classes that suggest class-specific functions. They are commonly induced upon the attack of pathogens and by various sources of stress, which led to associating them with plant defense in general. However, it is becoming apparent that most of them display several functions during the plant life cycle, including taking part in developmental processes such as pollination and embryo development. The number of chitinases combined with their multiple functions has been an obstacle to a better understanding of their role in plants. It is therefore important to identify and inventory all chitinase genes of a plant species to be able to dissect their function and understand the relations between the different classes. Complete sequencing of the Arabidopsis genome has made this task feasible and we present here a survey of all putative chitinase-encoding genes accompanied by a detailed analysis of their sequence. Based on their characteristics and on studies on other plant chitinases, we propose an overview of their possible functions as well as modified annotations for some of them.
Collapse
Affiliation(s)
- Paul A. Passarinho
- Wageningen University, Departement of Plant Sciences, Laboratory of Molecular Biology, Dreijenlaan 3, 6703 HA Wageningen, The Netherlands
- Present address: Plant Research International, Business Unit “Plant Development and Reproduction”, Cluster “Seed and Reproduction Strategies”, P.O. Box 16, 6700 AA Wageningen, The Netherlands
| | - Sacco C. de Vries
- Wageningen University, Departement of Plant Sciences, Laboratory of Molecular Biology, Dreijenlaan 3, 6703 HA Wageningen, The Netherlands
- Author for correspondence.
| |
Collapse
|
25
|
Dietz KJ. The Extracellular Matrix of the Plant Cell: Location of Signal Perception, Transduction and Response. ACTA ACUST UNITED AC 2001. [DOI: 10.1007/978-3-642-56849-7_11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
|
26
|
Gilson P, Gaspar YM, Oxley D, Youl JJ, Bacic A. NaAGP4 is an arabinogalactan protein whose expression is suppressed by wounding and fungal infection in Nicotiana alata. PROTOPLASMA 2001; 215:128-39. [PMID: 11732052 DOI: 10.1007/bf01280309] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Arabinogalactan proteins (AGPs) are proteoglycans secreted by plant cells that have been implicated in plant growth and development. Most AGPs cloned to date possess highly labile glycosylphosphatidylinositol (GPI) lipid anchors. These anchors transiently attach AGPs to the plasma membrane before they are released into the cell wall following GPI anchor hydrolysis. We have isolated and partially sequenced the protein core of an AGP purified from styles of Nicotiana alata. The protein sequence data were utilised to clone the AGP's gene, NaAGP4. This AGP shares about 78% sequence identity with the tomato AGP LeAGP-1. RNA gel blot analyses of different plant organs indicate that NaAGP4 is expressed in the same tissues and at similar levels as LeAGP-1. Furthermore, NaAGP4 like LeAGP-1 is rapidly suppressed by tissue wounding and by pathogen infection. We believe NaAGP4 and LeAGP-1 are the first described examples of orthologous AGPs from different plant species. In contrast, another AGP from N. alata, NaAGP1, is comparatively unaffected by wounding and pathogen infection, although this AGP is expressed in similar tissues and at similar levels as NaAGP4.
Collapse
Affiliation(s)
- P Gilson
- Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Victoria 3010, Australia
| | | | | | | | | |
Collapse
|