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Abdel-Aziz HMM, Rizwan M. Chemically synthesized silver nanoparticles induced physio-chemical and chloroplast ultrastructural changes in broad bean seedlings. Chemosphere 2019; 235:1066-1072. [PMID: 31561296 DOI: 10.1016/j.chemosphere.2019.07.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 06/25/2019] [Accepted: 07/04/2019] [Indexed: 06/10/2023]
Abstract
This study was conducted to explore the effects of priming of seven-year-old aged seeds with different concentrations of silver nanoparticles (AgNPs) on growth of broad bean (Vicia faba L.). Seeds were primed with different concentrations of AgNPs for 6 h before growing in the plastic trays. Different growth parameters like growth attributes, photosynthetic pigments, carbohydrates, antioxidant enzymes and chloroplast ultrastructure were estimated after 14 days of germination. Priming with AgNPs affected the root and shoot growth attributes as compared with control depending upon concentrations of AgNPs. In all treatments, photosynthetic pigments increased significantly above control levels, but total soluble sugars decreased in 10 and 50 ppm AgNPs and slightly increased in 100 ppm AgNPs as compared with control. Starch accumulation was apparent in all treated seedlings above that of control levels. Mesophyll cells of all treated seedlings were altered with electron dense particles than control. Priming with AgNPs affected the chloroplast structure which appeared in the form of less stacking of Greene, formation of protrusions and extensions, irregular shape of chloroplasts as compared with spindle shaped regular chloroplasts of control. In all treatments, total phenols were slightly affected as compared with control. The antioxidant enzyme activities in seedlings varied with the dose and type of antioxidants. Overall, AgNPs adversely affected the chloroplast ultrastructure, but increased growth of seedlings and starch accumulation. Further studies are required to explore the effects of AgNPs on the long-term on crop productivity of aged seeds.
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Affiliation(s)
- Heba M M Abdel-Aziz
- Botany Department, Faculty of Science, Mansoura University, 35516, Mansoura, Egypt
| | - Muhammad Rizwan
- Department of Environmental Sciences and Engineering, Government College University, Allama Iqbal Road, 38000, Faisalabad, Pakistan.
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2
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Zhao X, Huang L, Kang L, Jetter R, Yao L, Li Y, Xiao Y, Wang D, Xiao Q, Ni Y, Guo Y. Comparative analyses of cuticular waxes on various organs of faba bean (Vicia faba L.). Plant Physiol Biochem 2019; 139:102-112. [PMID: 30884413 DOI: 10.1016/j.plaphy.2019.03.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/08/2019] [Accepted: 03/08/2019] [Indexed: 06/09/2023]
Abstract
Cuticular waxes cover the plant surface and serve as hydrophobic layer, exhibiting various wax profiles between plant species and plant organs. This paper reports comprehensive analysis of the waxes on organs exposed to air, including leaf, stem, pod pericarp, and petals (banner, wing and keel), and on seed coat enwrapped in pod pericarp of faba bean (Vicia faba). In total 7 classes of wax compounds were identified, including fatty acids, primary alcohols, alkyl esters, aldehydes, alkanes, cinnamyl alcohol esters, and alkylresorcinols. Overall, primary alcohols dominated the waxes on leaves and the seed coat enwrapped in pod pericarp, alkanes accumulated largely in stem and petals, whereas alkylresorcinols were observed in leaf, stem and pod pericarp. Organs exposed to air had higher coverage (>1.2 μg/cm2) than those on seed coat (<0.8 μg/cm2), and keel having the highest wax coverage. Meanwhile, the wax coverage on seed coat reduced during the seed development. The variations of wax coverages, compound class distributions and chain length profiles among organs suggested that wax depositions were associated with their ecophysiological functions, and the enzymes involved in wax biosynthesis also showed organ-specific.
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Affiliation(s)
- Xiao Zhao
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Lei Huang
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Lin Kang
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Reinhard Jetter
- Department of Botany, University of British Columbia, 6270 University Boulevard, Vancouver, BC V6T 1Z4, Canada
| | - Luhua Yao
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Yang Li
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Yu Xiao
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Dengke Wang
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Qianlin Xiao
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Yu Ni
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China
| | - Yanjun Guo
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China.
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Rybaczek D. Ultrastructural changes associated with the induction of premature chromosome condensation in Vicia faba root meristem cells. Plant Cell Rep 2014; 33:1547-1564. [PMID: 24898011 PMCID: PMC4133037 DOI: 10.1007/s00299-014-1637-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 05/15/2014] [Accepted: 05/19/2014] [Indexed: 06/03/2023]
Abstract
PCC induction is regulated by several signaling pathways, and all observed effects associated with PCC induction are strongly dependent on the mechanism of action of each PCC inducer used. Electron microscopic observations of cells with symptoms of premature chromosome condensation (PCC) showed that the interphase chromatin and mitotic chromosomes differed with respect to a chemical compound inducing PCC. Induction of this process under the influence of hydroxyurea and caffeine as well as hydroxyurea and sodium metavanadate led to a slight decrease in interphase chromatin condensation and the formation of chromosomes with a considerably loosened structure in comparison with the control. Incubation in the mixture of hydroxyurea and 2-aminopurine brought about clear chromatin dispersion in interphase and very strong mitotic chromosome condensation. Electron microscopic examinations also revealed the characteristic features of the structural organization of cytoplasm of Vicia faba root meristems, which seemed to be dependent on the type of the PCC inducer used. The presence of the following was observed: (i) large plastids filled with starch grains (caffeine), (ii) mitochondria and plastids of electron dense matrix with dilated invaginations of their internal membranes (2-aminopurine), and (iii) large mitochondria of electron clear matrix and plastids containing protein crystals in their interior (sodium metavanadate). Moreover, since caffeine causes either the most effective loosening of chromatin fibrils (within the prematurely condensed chromosomes) or induction of starch formation (in the plastids surrounding the nuclei), this may be a proof that demonstrates the existence of a link between physical accessibility to chromatin and the effectiveness of cellular signaling (e.g., phosphothreonine-connected).
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Affiliation(s)
- Dorota Rybaczek
- Department of Cytophysiology, Institute of Experimental Biology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Lodz, Poland,
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Wang C, Liu H, Chen J, Tian Y, Shi J, Li D, Guo C, Ma Q. Carboxylated multi-walled carbon nanotubes aggravated biochemical and subcellular damages in leaves of broad bean (Vicia faba L.) seedlings under combined stress of lead and cadmium. J Hazard Mater 2014; 274:404-412. [PMID: 24806869 DOI: 10.1016/j.jhazmat.2014.04.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 03/31/2014] [Accepted: 04/17/2014] [Indexed: 06/03/2023]
Abstract
Increasing industrialization of multi-walled carbon nanotubes (MWCNTs) would inevitably lead to their release into the environment and combination with heavy metals. However, studies concerning the combined effects of MWCNTs and heavy metals on agricultural crops are limited. Herein, effects and mechanisms of carboxylated MWCNTs (MWCNTs-COOH) (2.5, 5 and 10mg/L) and their combination with 20 μM Pb and 5 μM Cd (shortened as Pb+Cd) on Vicia faba L. seedlings were investigated. The results showed that the MWCNTs-COOH disturbed the imbalance of nutrient elements, and caused oxidative stress and damages in the leaves. Additionally, the combination of MWCNTs-COOH with Pb+Cd resulted in enrichment of Pb and Cd, and deterioration of oxidative damages compared with the treatments of MWCNTs-COOH or Pb+Cd alone in the leaves. As the results, the concentrations of MWCNTs-COOH not only caused oxidative stress, but also exacerbated the biochemical and subcellular damages due to the treatment of Pb+Cd in the leaves. It also suggests that persistent release of MWCNTs-COOH into the environment may cause phytotoxicity and aggravate ecological risks due to combination of heavy metals.
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Affiliation(s)
- Chengrun Wang
- School of Life Science, Huainan Normal University, Huainan 232001, China.
| | - Haitao Liu
- School of Life Science, Huainan Normal University, Huainan 232001, China
| | - Jinyun Chen
- School of Life Science, Huainan Normal University, Huainan 232001, China
| | - Yuan Tian
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA
| | - Jian Shi
- School of Life Science, Huainan Normal University, Huainan 232001, China
| | - Dongdong Li
- School of Life Science, Huainan Normal University, Huainan 232001, China
| | - Chen Guo
- School of Life Science, Huainan Normal University, Huainan 232001, China
| | - Qingping Ma
- School of Life Science, Huainan Normal University, Huainan 232001, China
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Polit JT, Ciereszko I. Sucrose synthase activity and carbohydrates content in relation to phosphorylation status of Vicia faba root meristems during reactivation from sugar depletion. J Plant Physiol 2012; 169:1597-1606. [PMID: 22770419 DOI: 10.1016/j.jplph.2012.04.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 04/25/2012] [Accepted: 04/27/2012] [Indexed: 06/01/2023]
Abstract
Carbohydrate starvation of Vicia faba root meristems leads to readjustment of carbohydrate metabolism and blocks the cell cycle in two principal control points (PCP1/2). The cell cycle reactivation is possible after sucrose provision, although with a delay of about 12h. During this period, the cells are sensitive to 6-dimethylaminopurine (6-DMAP) and okadaic acid (OA), inhibitors of protein kinases and phosphatases, respectively. The aim of the present study was to investigate whether those inhibitors are involved in inhibition of cell cycle revival through interference with the activities of two sucrose-cleaving enzymes: sucrose synthase (SuSy; EC 2.4.1.13) and invertase (INV; EC 3.2.1.26). In sugar-starved cells, the in situ activity of both enzymes decreased significantly. Following supplementation of root meristems with sugar, INV remained inactive, but SuSy activity increased. Despite the lack of INV activity, glucose was present in meristem cells, but its content was low in cells treated with OA. In the latter case, the size of plastids was reduced, they had less starch, and Golgi structures were affected. In sugar-starved cells, SuSy activity was induced more by exogenous sucrose than by glucose. The sucrose-induced activity was strongly inhibited by OA (less by 6-DMAP) at early stages of regeneration, but not at the stages preceding DNA replication or mitotic activities. The results indicate that prolongation of regeneration and a marked decrease in the number of cells resuming proliferation (observed in previous studies) and resulting from the action of inhibitors, are correlated with the process of SuSy activation at the beginning of regeneration from sugar starvation.
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Affiliation(s)
- Justyna Teresa Polit
- Department of Cytophysiology, University of Łódź, ul. Pomorska 141/143, 90-236 Łódź, Poland.
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Beyer D, Tándor I, Kónya Z, Bátori R, Roszik J, Vereb G, Erdődi F, Vasas G, M-Hamvas M, Jambrovics K, Máthé C. Microcystin-LR, a protein phosphatase inhibitor, induces alterations in mitotic chromatin and microtubule organization leading to the formation of micronuclei in Vicia faba. Ann Bot 2012; 110:797-808. [PMID: 22819947 PMCID: PMC3423812 DOI: 10.1093/aob/mcs154] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 05/03/2012] [Indexed: 05/31/2023]
Abstract
BACKGROUND AND AIMS Microcystin-LR (MCY-LR) is a cyanobacterial toxin, a specific inhibitor of type 1 and 2A protein phosphatases (PP1 and PP2A) with significant impact on aquatic ecosystems. It has the potential to alter regulation of the plant cell cycle. The aim of this study was improved understanding of the mitotic alterations induced by cyanotoxin in Vicia faba, a model organism for plant cell biology studies. METHODS Vicia faba seedlings were treated over the long and short term with MCY-LR purified in our laboratory. Short-term treatments were performed on root meristems synchronized with hydroxylurea. Sections of lateral root tips were labelled for chromatin, phosphorylated histone H3 and β-tubulin via histochemical and immunohistochemical methods. Mitotic activity and the occurrence of mitotic alterations were detected and analysed by fluorescence microscopy. The phosphorylation state of histone H3 was studied by Western blotting. KEY RESULTS Long-term MCY-LR exposure of lateral root tip meristems increased the percentage of either early or late mitosis in a concentration-dependent manner. We observed hypercondensed chromosomes and altered sister chromatid segregation (lagging chromosomes) leading to the formation of micronuclei, accompanied by the formation of disrupted, multipolar and monopolar spindles, disrupted phragmoplasts and the hyperphosphorylation of histone H3 at Ser10. Short-term MCY-LR treatment of synchronized cells showed that PP1 and PP2A inhibition delayed the onset of anaphase at 1 µg mL(-1) MCY-LR, accelerated cell cycle at 10 µg mL(-1) MCY-LR and induced the formation of lagging chromosomes. In this case mitotic microtubule alterations were not detected, but histone H3 was hyperphosphorylated. CONCLUSIONS MCY-LR delayed metaphase-anaphase transition. Consequently, it induced aberrant chromatid segregation and micronucleus formation that could be associated with both H3 hyperphosphorylation and altered microtubule organization. However, these two phenomena seemed to be independent. The toxin may be a useful tool in the study of plant cell cycle regulation.
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Affiliation(s)
- Dániel Beyer
- University of Debrecen, Faculty of Science and Technology, Department of Botany, PO Box 14, H-4010, Debrecen, Hungary
- University of Debrecen, Medical and Health Science Centre, Department of Biophysics and Cell Biology, H-4032, Debrecen, Hungary
| | - Ildikó Tándor
- University of Debrecen, Faculty of Science and Technology, Department of Botany, PO Box 14, H-4010, Debrecen, Hungary
| | - Zoltán Kónya
- University of Debrecen, Faculty of Science and Technology, Department of Botany, PO Box 14, H-4010, Debrecen, Hungary
- University of Debrecen, Medical and Health Science Centre, Department of Medical Chemistry, H-4012 Debrecen, Hungary
| | - Róbert Bátori
- University of Debrecen, Medical and Health Science Centre, Department of Medical Chemistry, H-4012 Debrecen, Hungary
| | - Janos Roszik
- University of Debrecen, Medical and Health Science Centre, Department of Biophysics and Cell Biology, H-4032, Debrecen, Hungary
| | - György Vereb
- University of Debrecen, Medical and Health Science Centre, Department of Biophysics and Cell Biology, H-4032, Debrecen, Hungary
| | - Ferenc Erdődi
- University of Debrecen, Medical and Health Science Centre, Department of Medical Chemistry, H-4012 Debrecen, Hungary
| | - Gábor Vasas
- University of Debrecen, Faculty of Science and Technology, Department of Botany, PO Box 14, H-4010, Debrecen, Hungary
| | - Márta M-Hamvas
- University of Debrecen, Faculty of Science and Technology, Department of Botany, PO Box 14, H-4010, Debrecen, Hungary
| | - Károly Jambrovics
- University of Debrecen, Faculty of Science and Technology, Department of Botany, PO Box 14, H-4010, Debrecen, Hungary
| | - Csaba Máthé
- University of Debrecen, Faculty of Science and Technology, Department of Botany, PO Box 14, H-4010, Debrecen, Hungary
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Li B, Liu G, Deng Y, Xie M, Feng Z, Sun M, Zhao Y, Liang L, Ding N, Jia W. Excretion and folding of plasmalemma function to accommodate alterations in guard cell volume during stomatal closure in Vicia faba L. J Exp Bot 2010; 61:3749-58. [PMID: 20603284 PMCID: PMC2921211 DOI: 10.1093/jxb/erq197] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Stomatal movement results in large and repetitive changes in cell volume and consequently surface area. While endocytosis has been extensively studied and is thought to be a major mechanism for accommodating the volume changes as evidenced mainly by fluorescent labelling and confocal imaging, studies at the ultrastructural level in intact guard cells of stomata regulated by natural factors have never been reported. Here, it is reported that excretion and folding of the plasmalemma are critical for accommodating the volume alterations in intact guard cells in Vicia faba L. Using transmission electron microscopy in combination with laser confocal microscopy, it was observed that in fully opened stomata the plasmalemma was smooth and tightly adhered to the cell walls while a whole large vacuole appeared in the cell. In the closed stomata, besides vacuole fragmentation, endocytosis of the tonoplast rather than the plasmalemma commonly occurred. Importantly, in stomata where pore closure was induced by circadian rhythm or CO(2), numerous tiny vesicles were found outside the plasmalemma and, moreover, extensive folding of the plasmalemma could also be found in some regions of the cells. Additionally, an unknown structure was found at the interface between the plasmalemma and cell walls, especially in those areas of the cell where extensive folding occurred, suggesting that plasmalemma turnover is possibly associated with an interaction between the plasmalemma and cell walls. Collectively, the results strongly indicate that excretion and folding of the plasmalemma are critical for the accommodation of the cell volume alterations during stomatal movement.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Wensuo Jia
- To whom correspondence should be addressed. E-mail:
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Furch ACU, van Bel AJE, Fricker MD, Felle HH, Fuchs M, Hafke JB. Sieve element Ca2+ channels as relay stations between remote stimuli and sieve tube occlusion in Vicia faba. Plant Cell 2009; 21:2118-32. [PMID: 19602624 PMCID: PMC2729599 DOI: 10.1105/tpc.108.063107] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Damage induces remote occlusion of sieve tubes in Vicia faba by forisome dispersion, triggered during the passage of an electropotential wave (EPW). This study addresses the role of Ca2+ channels and cytosolic Ca2+ elevation as a link between EPWs and forisome dispersion. Ca2+ channel antagonists affect the initial phase of the EPW as well as the prolonged plateau phase. Resting levels of sieve tube Ca2+ of approximately 50 nM were independently estimated using Ca2+-selective electrodes and a Ca2+-sensitive dye. Transient changes in cytosolic Ca2+ were observed in phloem tissue in response to remote stimuli and showed profiles similar to those of EPWs. The measured elevation of Ca2+ in sieve tubes was below the threshold necessary for forisome dispersion. Therefore, forisomes need to be associated with Ca2+ release sites. We found an association between forisomes and endoplasmic reticulum (ER) at sieve plates and pore-plasmodesma units where high-affinity binding of a fluorescent Ca2+ channel blocker mapped an increased density of Ca2+ channels. In conclusion, propagation of EPWs in response to remote stimuli is linked to forisome dispersion through transiently high levels of parietal Ca2+, release of which depends on both plasma membrane and ER Ca2+ channels.
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Affiliation(s)
- Alexandra C U Furch
- Plant Cell Biology Research Group, Institute of General Botany, Justus-Liebig-University, D-35390 Giessen, Germany
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Dibley SJ, Zhou Y, Andriunas FA, Talbot MJ, Offler CE, Patrick JW, McCurdy DW. Early gene expression programs accompanying trans-differentiation of epidermal cells of Vicia faba cotyledons into transfer cells. New Phytol 2009; 182:863-877. [PMID: 19383101 DOI: 10.1111/j.1469-8137.2009.02822.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Transfer cells (TCs) trans-differentiate from differentiated cells by developing extensive wall ingrowths that enhance plasma membrane transport of nutrients. Here, we investigated transcriptional changes accompanying induction of TC development in adaxial epidermal cells of cultured Vicia faba cotyledons. Global changes in gene expression revealed by cDNA-AFLP were compared between adaxial epidermal cells during induction (3 h) and subsequent building (24 h) of wall ingrowths, and in cells of adjoining storage parenchyma tissue, which do not form wall ingrowths. A total of 5795 transcript-derived fragments (TDFs) were detected; of these, 264 TDFs showed epidermal-specific changes in gene expression and a further 207 TDFs were differentially expressed in both epidermal and storage parenchyma cells. Genes involved in signalling (auxin/ethylene), metabolism (mitochondrial; storage product hydrolysis), cell division, vesicle trafficking and cell wall biosynthesis were specifically induced in epidermal TCs. Blockers of auxin action and vesicle trafficking inhibited ingrowth formation and marked increases in cell division accompanied TC development. Auxin and possibly ethylene signalling cascades induce epidermal cells of V. faba cotyledons to trans-differentiate into TCs. Trans-differentiation is initiated by rapid de-differentiation to a mitotic state accompanied by mitochondrial biogenesis driving storage product hydrolysis to fuel wall ingrowth formation orchestrated by a modified vesicle trafficking mechanism.
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Affiliation(s)
- Stephen J Dibley
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Yuchan Zhou
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Felicity A Andriunas
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Mark J Talbot
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Christina E Offler
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - John W Patrick
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - David W McCurdy
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales 2308, Australia
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Polit JT. Protein phosphorylation in Vicia faba root meristem cells during the first steps of leaving principal control points after sucrose application. Plant Cell Rep 2009; 28:165-173. [PMID: 19023574 DOI: 10.1007/s00299-008-0642-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Accepted: 11/02/2008] [Indexed: 05/27/2023]
Abstract
Before Vicia faba root meristem cells stopped by carbohydrate starvation in principal control points (PCP1 and PCP2) start sucrose induced replication and division they go through a phase of metabolic regeneration. This interval is characterised st great sensitivity to the inhibitors of cyclin-dependent protein kinases and protein phosphatases (PPs). In the present research, changes of phosphoprotein levels in the nucleolus, nucleus and cytoplasm were analysed using okadaic acid and 6-dimethylaminopurine (6-DMAP) during the first period of cell regeneration in sucrose (0-3 h). It was established that when the cells start to leave checkpoints, the balance between protein phosphorylation and dephosphorylation shifts towards the intensified activity of PPs. Furthermore, it was also established that the structures appearing during cell regeneration, which were located around cell nuclei and which contained large amounts of phosphorylated proteins, were plastids. The reactions of protein phosphorylation which took place in the plastids were directly correlated with starch synthesis and were stopped by inactivation of protein phosphatases (PP1 and/or PP2A).
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Radwan DEM, Lu G, Fayez KA, Mahmoud SY. Protective action of salicylic acid against bean yellow mosaic virus infection in Vicia faba leaves. J Plant Physiol 2008; 165:845-57. [PMID: 17920158 DOI: 10.1016/j.jplph.2007.07.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2007] [Revised: 07/04/2007] [Accepted: 07/05/2007] [Indexed: 05/11/2023]
Abstract
In this study, morphological, ultrastructural and physiological modifications of faba bean (Vicia faba cv Giza 461) leaves in response to bean yellow mosaic virus (BYMV) infection and salicylic acid (SA) treatments were examined. Under BYMV stress, leaves showed symptoms including severe mosaic, mottling, crinkling, size reduction and deformations. Three weeks after virus inoculation, photosynthetic rate, pigment contents and transpiration rate were significantly reduced in response to BYMV infection. Ultrastructural investigations of BYMV-infected leaves demonstrated that most chloroplasts with increased stromal area became spherical in shape and some lost their envelopes, either partially or totally. The internal structures of chloroplast, grana and thylakoids were dilated. Two kinds of inclusions were detected in BYMV-infected leaves: straight or slightly curved bands sometimes coiled or looped at the end, and electron opaque crystals with varied shapes. BYMV-infected cells showed lower chloroplast number in comparison to the control. Spraying of SA on faba bean leaves helped to reduce or prevent the harmful effects produced after virus infection. Application of 100 microM SA three days before inoculation restored the metabolism of infected leaves to the levels of healthy controls. SA treatment improved plant health by increasing the photosynthesis rates, pigment contents and levels of other parameters studied similar to control values. Moreover, SA treatment increased plant resistance against BYMV. This was observed through induction of chloroplast number, reduction in percentage of infected plants, decrease in disease severity and virus concentration of plants treated with SA prior to BYMV inoculation. Cells of SA-treated samples showed well-developed chloroplasts with many starch grains and well-organized cell organelles. The present results provide an overview of the negative effects on faba bean leaves due to BYMV infection from physiological and subcellular perspectives. Also, a role of SA involved in induction of resistance against BYMV infection in bean plants is discussed.
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Liu X, Jia WS, Wang YQ, Lou CH, Zhang SQ. [Effects of wounding on jasmonic acid distribution in vicia faba leaves]. Fen Zi Xi Bao Sheng Wu Xue Bao 2007; 40:233-8. [PMID: 17674776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Higher plants have to cope with environmental stimulus such as wounding. Jasmonic acid (JA) is an essential long-distance signaling compound. There is rare information about JA cellular and subcellular localization by now. In this work, using the immuno-fluorescence and immuno-gold electron microscopy, distributions of JA were determined in different cells of Vicia faba leaf. It showed that JA existed in the epidermal cells, mesophyll cells and guard cells, mainly localized in the cytosol and chloroplast of mesophyll cells, cell wall of epidermal cells, and cytosol, cell wall, chloroplast and nucleus of guard cells. Wounding increased JA accumulation in the apoplast and guard cells. Our results suggest that JA plays an important role as a signal in the defense response and involves in regulation of the stomatal movement in response to wounding stress.
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Affiliation(s)
- Xin Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Science,China Agricultural University, Beijing 100094, China
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Feng S, Wang X, Wei G, Peng P, Yang Y, Cao Z. Leachates of municipal solid waste incineration bottom ash from Macao: heavy metal concentrations and genotoxicity. Chemosphere 2007; 67:1133-7. [PMID: 17217988 DOI: 10.1016/j.chemosphere.2006.11.030] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2006] [Revised: 11/01/2006] [Accepted: 11/10/2006] [Indexed: 05/13/2023]
Abstract
Heavy metals in municipal solid waste incineration bottom ash (MSWIBA) may leach into soil and groundwater and pose long-term risks to the environment. In this study, toxicity characteristic leaching procedure (TCLP) was carried out on the MSWIBA from Macao. Heavy metals in leachates were determined by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectrometry (ICP-AES), and genotoxicity of leachates was also evaluated by micronucleus (MN) assay with Vicia faba root tip cells. The results showed that the concentrations of aluminium (Al), manganese (Mn), cobalt (Co), cadmium (Cd) and mercury (Hg) in the leachates were less than 0.01 mg l(-1), and those of iron (Fe), copper (Cu) and molybdenum (Mo) were less than 0.1 mg l(-1). The concentrations of chromium (Cr), zinc (Zn), selemium (Se), strontium (Sr), barium (Ba) and caesium (Cs) were between 0.11 mg l(-1) and 2.19 mg l(-1). Lead (Pb) concentrations, in particular, reached as high as 19.6 mg l(-1), significantly exceeding the maximum concentration limit (5 mg l(-1) for lead by TCLP). Compared with the negative group, a significant increase of MN frequencies was observed in the leachate-exposed groups (P<0.05). With the increase of heavy metals in the leachates, the toxic effects on the Vicia faba root tip cells increased, implying that heavy metals were the main factors causing the genotoxic effects. Our results suggested that apart from chemical analysis, bioassays like the MN assay of Vicia faba root tip cells should also be included in a battery of tests to assess the eco-environmental risks of bottom ashes before decisions can be made on the utilization, treatment or disposal.
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Affiliation(s)
- Shaolong Feng
- The School of Public Health, Nanhua University, Hengyang 421001, China
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Polit JT, Kazmierczak A. Okadaic acid (1 microM) accelerates S phase and mitosis but inhibits heterochromatin replication and metaphase anaphase transition in Vicia faba meristem cells. J Exp Bot 2007; 58:2785-97. [PMID: 17609530 DOI: 10.1093/jxb/erm148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Protein kinases and phosphatases are the foremost agents which take part in cell cycle regulation in both plants and other eukaryotes. Protein kinases are a very well examined group of proteins with respect to chemical structure and function. Nowadays protein phosphatases, including PP1 and PP2A belonging to the PSP family, are the focus of interest. Okadaic acid (OA) which is a specific inhibitor of protein phosphatase activity is widely used to study them. In the present research, the involvement of OA-sensitive phosphatases in the regulation of progression of the plant cell cycle was analysed (in planta) using Vicia faba root meristems synchronized with hydroxyurea and divided into five series. Each series was treated with 1 muM OA for 3 h for different time periods corresponding to the consecutive cell cycle phases. The results showed that in the OA-treated cells DNA replication and mitosis began earlier than in the control cells, since G(1) and G(2) phases were significantly shorter and the H1 histone kinases activity was higher. Moreover, autoradiography and morphological analyses of mitotic figures revealed that the OA-treated cells entered mitosis before the end of heterochromatin replication. An immunocytochemical search showed that earlier initiation of S phase in the OA-treated cells correlated with more abundant phosphorylation of Rb-like protein in comparison with the control cells. OA also induced significant condensation of metaphase chromosomes and blocked metaphase-anaphase transition.
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Affiliation(s)
- Justyna Teresa Polit
- Department of Cytophysiology, University of Łódź, 90-231 Łódź, ul. Pilarskiego 14, Poland.
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15
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Abdel Migid HM, Azab YA, Ibrahim WM. Use of plant genotoxicity bioassay for the evaluation of efficiency of algal biofilters in bioremediation of toxic industrial effluent. Ecotoxicol Environ Saf 2007; 66:57-64. [PMID: 16376989 DOI: 10.1016/j.ecoenv.2005.10.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2004] [Revised: 09/10/2005] [Accepted: 10/15/2005] [Indexed: 05/05/2023]
Abstract
The toxicity and efficacy of an algal-based bioremediation technology were assessed through bioassays for ecological risk of contaminated industrial effluents. The algal bioremoval of heavy metals was evaluated using an in vitro approach. Phytogenotoxicity tests were conducted with Allium cepa and Vicia faba plants to evaluate the genotoxicity of the industrial effluents before and after treatment with different kinds of algal biofilters (BF). Root cells were exposed for 24 h to different dilutions of both raw and treated effluent of a chemical fertilizer factory. Three cytogenetic endpoints were used to assess the mutagenic potencies of the industrial effluent: mitotic inhibition, mitotic chromosome aberrations, and nuclear irregularities in interphase cells. Before algal treatment, the industrial effluent caused strong genotoxic effects represented by severe inhibition in mitotic activity of meristematic cells and high frequency of both chromosome and nucleus abnormalities. After algal treatment, the cytotoxic effects of 30% and 60% concentrations of the treated effluent were comparable to those of 5% and 10% concentrations before treatment, respectively, and the frequency of both chromosome and nuclear abnormalities declined by approximately 50%. Statistical analysis of the data indicates a significant reduction in genotoxicity associated with a remarkable reduction in heavy metal concentrations after bioremediation by algal BF. The Allium and Vicia genotoxicity approach was effective in monitoring bioremediated effluent for toxicity.
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Affiliation(s)
- Hala M Abdel Migid
- Botany Department, Faculty of Science, Mansoura University, Mansoura, Dakahlia 23355, Egypt.
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16
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Talbot MJ, Wasteneys GO, Offler CE, McCurdy DW. Cellulose synthesis is required for deposition of reticulate wall ingrowths in transfer cells. Plant Cell Physiol 2007; 48:147-58. [PMID: 17169922 DOI: 10.1093/pcp/pcl046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Despite the recognized physiological importance of transfer cells, little is known about how these specialized cells achieve localized deposition of cell wall material, leading to amplification of plasma membrane surface area and enhanced membrane transport capacity. This study establishes that cellulose synthesis is a key early factor in the construction of 'reticulate' wall ingrowths, an elaborate but common form of localized wall deposition characteristic of most transfer cells. Using field emission scanning electron microscopy, wall ingrowths were first visible in epidermal transfer cells of Faba bean cotyledons as raised 'patches' of disorganized and tangled cellulosic material, and, from these structures, ingrowths emerged via further deposition of wall material. The cellulose biosynthesis inhibitors 2,6-dichlorobenzonitrile and isoxaben both caused dramatic reductions in the number of cells depositing wall ingrowths, altered wall ingrowth morphology and visibly disrupted microfibril structure. The restriction of cellulose deposition to discrete patches suggests a novel mechanism for cellulose synthesis in this circumstance. Overall, these results implicate a central role for cellulose synthesis in reticulate wall ingrowth morphology, especially at the initial stage of ingrowth formation, possibly by providing a template for the self-assembly of wall polymers.
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Affiliation(s)
- Mark J Talbot
- School of Environmental and Life Sciences, The University of Newcastle, Newcastle, NSW 2308, Australia
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17
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Li YH, Hong J, Xue L, Yang Y, Zhou XP, Jiang DA. [Effects of Broad bean wilt virus 2 isolate infection on photosynthetic activities and chloroplast ultrastructure in broad bean leaves]. Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao 2006; 32:490-6. [PMID: 16957402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The effects of Broad bean wilt virus 2 (BBWV 2) isolate B935 and PV131 infection on photosynthetic activities and chloroplast ultrastructure in broad bean (Vicia faba) were investigated. As the disease progressed, net photosynthetic rate (P(n)), stomatal conductance (G(s)) of leaves, the chlorophyll content and chlorophyll a/b ratio decreased while the intercellular CO(2) concentration (C(i)) of leaves rose in comparison with that of the healthy plants (Figs. 1, 2). After BBWV 2 infection, F(v)/F(m), F(v)'/F(m)', Phi(PSII) and q(P) values all became lower, but the NPQ values were higher, than the healthy control plants (Fig. 3). Electron microscopy showed that BBWV 2 infection disrupted the chloroplast structure. Most of the B935-infected chloroplasts showed inhibition of lamellar development or membrane vesiculation (Fig. 4B, C) and PV131-infected chloroplasts showed swollen or disintegrated membrane (Fig. 4D-F). Chloroplasts of PV131-infected leaves were different from those of normal ones to a higher degree than those of the B935-infected ones, which suggests that the disruption of chloroplast structure by virus invasion is responsible for the suppression of photosynthesis, which is more serious with PV131 than with B935.
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Affiliation(s)
- Yan-Hong Li
- Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China
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18
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Li YH, Hong J, Xue L, Yang Y, Zhou XP, Jiang DA. [Effects of Broad bean wilt virus 2 isolate infection on photosynthetic activities and chloroplast ultrastructure in broad bean leaves]. Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao 2006. [PMID: 16957402 DOI: 10.3321/j.issn:1671-3877.2006.04.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The effects of Broad bean wilt virus 2 (BBWV 2) isolate B935 and PV131 infection on photosynthetic activities and chloroplast ultrastructure in broad bean (Vicia faba) were investigated. As the disease progressed, net photosynthetic rate (P(n)), stomatal conductance (G(s)) of leaves, the chlorophyll content and chlorophyll a/b ratio decreased while the intercellular CO(2) concentration (C(i)) of leaves rose in comparison with that of the healthy plants (Figs. 1, 2). After BBWV 2 infection, F(v)/F(m), F(v)'/F(m)', Phi(PSII) and q(P) values all became lower, but the NPQ values were higher, than the healthy control plants (Fig. 3). Electron microscopy showed that BBWV 2 infection disrupted the chloroplast structure. Most of the B935-infected chloroplasts showed inhibition of lamellar development or membrane vesiculation (Fig. 4B, C) and PV131-infected chloroplasts showed swollen or disintegrated membrane (Fig. 4D-F). Chloroplasts of PV131-infected leaves were different from those of normal ones to a higher degree than those of the B935-infected ones, which suggests that the disruption of chloroplast structure by virus invasion is responsible for the suppression of photosynthesis, which is more serious with PV131 than with B935.
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Affiliation(s)
- Yan-Hong Li
- Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China
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19
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Hong J, Wang WB, Zhou XP, Hu DW. [Ultrastructural observation related to cell-to-cell movement and long-distance systemic transport on the hosts infected with BBWV 2]. Wei Sheng Wu Xue Bao 2006; 46:441-4. [PMID: 16933617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The alteration of ultrastructure in Pisum sativum and Vicia faba leaf cells infected with B935 isolate of BBWV 2 were investigated by electron microscopy, immunogold-labeling technique. The results showed that the membranous proliferation, virus-formed crystals and tubular structures were found in leaf cells of two hosts. At early stages of infection, the tubules containing virus-like particles associate with plasmodesmata in mesophyll cell. Immunogold particles anti-BBWV 2 were localized to the plasmodesmata modified by tubules passing through them. The membranous proliferation and virus-formed tubules were also found in the parenchyma cells, companion cells and transfer cells of vascular bundle. Some virus-like particles located within sieve tube can be labeled immunogold particles anti-BBWV 2. These suggest that BBWV 2, similar CPMV, produce tubules extending into the plasmodesmata. Virions assembled in the cytoplasm are escorted to the tubular structures through interactions with their MP and are then transported to the adjacent cell. Many 160 nm in diameter virus-formed tubules in the cytoplasm, as a special aggregate, not directly relate to cell-to-cell movement; Intact virions are long-distance sustemic transported possibly through sieve elements.
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Affiliation(s)
- Jian Hong
- Center of Analysis and Measurement, Zhejiang University, Hangzhou 310029, China.
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20
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Fuchs J, Demidov D, Houben A, Schubert I. Chromosomal histone modification patterns--from conservation to diversity. Trends Plant Sci 2006; 11:199-208. [PMID: 16546438 DOI: 10.1016/j.tplants.2006.02.008] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Revised: 02/03/2006] [Accepted: 02/27/2006] [Indexed: 05/07/2023]
Abstract
The organization of DNA into chromatin regulates expression and maintenance (replication, repair, recombination, segregation) of genetic information in a dynamic manner. The N-terminal tails of the nucleosomal core histones are subjected to post-translational modifications such as acetylation, methylation, phosphorylation, ubiquitination, glycosylation, ADP-ribosylation, carbonylation and sumoylation. These modifications, together with DNA methylation, control the folding of the nucleosomal array into higher order structures and mediate signalling for cellular processes. Although histones and their modifications are highly conserved, recent data show that chromosomal distribution of individual modifications (acetylation, methylation, phosphorylation) can differ along the cell cycle as well as among and between groups of eukaryotes. This implies the possibility of evolutionary divergence in reading the "histone code".
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Affiliation(s)
- Jörg Fuchs
- Leibniz-Institute of Plant Genetics and Crop Plant Research, Corrensstrasse 3, D-06466 Gatersleben, Germany
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Kemen E, Kemen AC, Rafiqi M, Hempel U, Mendgen K, Hahn M, Voegele RT. Identification of a protein from rust fungi transferred from haustoria into infected plant cells. Mol Plant Microbe Interact 2005; 18:1130-9. [PMID: 16353548 DOI: 10.1094/mpmi-18-1130] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The formation of haustoria is one of the hallmarks of the interaction of obligate biotrophic fungi with their host plants. In addition to their role in nutrient uptake, it is hypothesized that haustoria are actively involved in establishing and maintaining the biotrophic relationship. We have identified a 24.3-kDa protein that exhibited a very unusual allocation. Rust transferred protein 1 from Uromyces fabae (Uf-RTP1p) was not only detected in the host parasite interface, the extrahaustorial matrix, but also inside infected plant cells by immunofluorescence and electron microscopy. Uf-RTP1p does not exhibit any similarity to sequences currently listed in the public databases. However, we identified a homolog of Uf-RTP1p in the related rust fungus Uromyces striatus (Us-RTP1p). The localization of Uf-RTP1p and Us-RTP1p inside infected plant cells was confirmed, using four independently raised polyclonal antibodies. Depending on the developmental stage of haustoria, Uf-RTP1p was found in increasing amounts in host cells, including the host nucleus. Putative nuclear localization signals (NLS) were found in the predicted RTP1p sequences. However, functional efficiency could only be verified for the Uf-RTP1p NLS by means of green fluorescent protein fusions in transformed tobacco protoplasts. Western blot analysis indicated that Uf-RTP1p and Us-RTP1p most likely enter the host cell as N-glycosylated proteins. However, the mechanism by which they cross the extrahaustorial membrane and accumulate in the host cytoplasm is unknown. The localization of RTP1p suggests that it might play an important role in the maintenance of the biotrophic interaction.
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Affiliation(s)
- Eric Kemen
- Phytopathologie, Fachbereich Biologie, Universität Konstanz, Germany
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Long H, Sun H, Zeng X, Hao S, Jiao M. Subnucleolar distribution and organization of L. rDNA in situ. Cell Biol Int 2004; 28:845-8. [PMID: 15566954 DOI: 10.1016/j.cellbi.2004.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2004] [Revised: 07/22/2004] [Accepted: 08/25/2004] [Indexed: 11/15/2022]
Abstract
The distribution and organization of nucleolar DNA in Vicia faba L. was analyzed by specific cytochemical staining using NAMA-Ur. The results showed that nucleolar DNA was distributed in the FCs and at the FC/DFC junctions. Statistical analysis showed that the rRNA genes occupied about one-third of the total dense fibrillar component region. The rDNA was condensed in some regions and uncondensed in others. Nucleolus-associated chromatin extended from outside the nucleolus to the periphery of the FCs via nucleolar channels, suggesting a possible origin for nucleolar DNA.
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Affiliation(s)
- Hong Long
- Institute of Genetics and Cell Biology, Northeast Normal University, Changchun 130024, China
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Liu H, Liao B, Lu S. [Toxicity of surfactant, acid rain and Cd2+ combined pollution to the nucleus of Vicia faba root tip cells]. Ying Yong Sheng Tai Xue Bao 2004; 15:493-6. [PMID: 15228004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
The toxicity of Cd2+ and its combination with surfactant or simulated acid rain to Vicia faba root tip cell was studied by using micro-nucleus technique. The results showed that the formation of micro-nucleus in Vicia faba root tip cell was strongly induced by Cd2+ in its concentration of 0-10.0 mg.L-1. The micro-nucleus rate was 13.85@1000 at 6.0 mg.L-1Cd2+, 4.53@1000 at 0 mg.L-1Cd2+, and the pollution index (PI) was 3.06. The micro-nucleus ratio and PI decreased when the accompanied surfactant LAS was also presented or the pH values decreased to 4.5 or 3.5. In the meantime, many deformed nuclei and grains were observed in the root tip cells. The growth of the Vicia faba roots was restrained, and the root cells were not easy to be scattered. Therefore, the toxicity of Cd2+ was increased by its combination with surfactant or acid rain. The Cd2+ toxicity to Vicia faba cells at pH3.5 was stronger than that at pH4.5. When the mutation effect of contaminant with high concentration or with strong toxicity to plant cell was tested, the contaminant should be diluted for at least three times, and hence, the highest micro-nucleus ratio and pollution index (PI) could be found.
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Affiliation(s)
- Hongyu Liu
- Department of Environmental Science, Hunan Agricultural University, Changsha 410128, China
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Hurst AC, Meckel T, Tayefeh S, Thiel G, Homann U. Trafficking of the plant potassium inward rectifier KAT1 in guard cell protoplasts of Vicia faba. Plant J 2004; 37:391-397. [PMID: 14731259 DOI: 10.1046/j.1365-313x.2003.01972.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Trafficking of K+ inward (Kin+) rectifying channels was analyzed in guard cells of Vicia faba transfected with the Kin+ rectifier from Arabidopsis thaliana KAT1 fused to the green fluorescent protein (GFP). Confocal images and whole-cell patch-clamp measurements confirmed the incorporation of active KAT1 channels into the plasma membrane of transfected guard cell protoplasts. The Kin+ rectifier current density of the plasma membrane was much larger in transfected protoplasts than in wild-type (wt) protoplasts. This shows a coupling between K+ channel synthesis and incorporation of the channel into the plasma membrane. Pressure-driven increase and decrease in surface area led to the incorporation and removal of vesicular membrane carrying active Kin+ rectifier in wt and transfected protoplasts. These vesicular membranes revealed a higher channel density than the plasma membrane, suggesting that Kin+ rectifier remains in clusters during trafficking to and from the plasma membrane. The observed results can be explained by a model illustrating that vesicles of a pre-plasma membrane pool carry K+ channels preferentially in clusters during constitutive and pressure-driven exo- and endocytosis.
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Affiliation(s)
- Annette C Hurst
- Institute of Botany, Technical University of Darmstadt, 64287 Darmstadt, Germany
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Wang HC, Xing M. [Localization of SC35 in the nucleolus and nucleoplasm of the root meristematic cells of Vicia faba]. Shi Yan Sheng Wu Xue Bao 1999; 32:277-87. [PMID: 12548810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
SC35 is a non-snRNP spliceosome component purified from mammalian cells by Fu and Maniatis in 1990. In vitro splicing assays showed that SC35 plays a key role in splicing site selection and ATP-dependent pre-spliceosome assembly. In the mammalian nucleus, SC35 has been localized to distinct and dynamic nuclear domains: immunofluorescence observations revealed the presence of SC35 in speckles distributed in various regions throughout the nucleoplasm, which, as identified with immunoelectron microscopy, correspond to the interchromatin granules (IGs) and perichromatin fibrils (PFs). However, there has been no report regarding the presence and distribution pattern of SC35 in higher plant nuclei. Engage in such studies will surely contribute to our understanding of RNA processing and the spatial organization or structure basis of this process in higher plant. In this article, we studied the distribution pattern of SC35 in the nucleus of the root meristematic cells of Vicia faba by immunoelectron microscopy. After immunolabeling with anti-SC35 mAb and protein A-colloidal gold, IGs and PFs in the nucleoplasm and dense fibrillar component (DFC) of the nucleolus were heavily labeled with gold particles, while only a few of the gold particles were found in fibrillar centers (FC) and nucleolar vacuoles (NV) of the nucleolus and the central domains of the condensed chromatin. Densities of gold particles in the areas of DFC and the area of IGs plus PFs were 65.89/microns 2 and 36.28/microns 2 respectively, much higher than that of the central domain of condensed chromatin and that of FC plus NV, which were only 5.90/microns 2 and 6.26/microns 2 respectively. This indicates that DFC of the nucleolus and the area of IGs plus PFs of the nucleoplasm are enriched with SC35 or SC35-like protein. The distribution pattern of SC35 or SC35-like protein in the nucleoplasm of Vicia faba is similar to that of the mammalian nuclei. To the authors' knowledge, it is a new finding that SC35 or SC35-like protein exists in the nucleolus.
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Affiliation(s)
- H C Wang
- Department of Bioengineering, Shenzhen University, Shenzhen 518060
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