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Vassileva V, Georgieva M, Todorov D, Mishev K. Small Sized Yet Powerful: Nuclear Distribution C Proteins in Plants. Plants (Basel) 2023; 13:119. [PMID: 38202427 PMCID: PMC10780334 DOI: 10.3390/plants13010119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/12/2023] [Accepted: 12/29/2023] [Indexed: 01/12/2024]
Abstract
The family of Nuclear Distribution C (NudC) proteins plays a pivotal and evolutionarily conserved role in all eukaryotes. In animal systems, these proteins influence vital cellular processes like cell division, protein folding, nuclear migration and positioning, intracellular transport, and stress response. This review synthesizes past and current research on NudC family members, focusing on their growing importance in plants and intricate contributions to plant growth, development, and stress tolerance. Leveraging information from available genomic databases, we conducted a thorough characterization of NudC family members, utilizing phylogenetic analysis and assessing gene structure, motif organization, and conserved protein domains. Our spotlight on two Arabidopsis NudC genes, BOB1 and NMig1, underscores their indispensable roles in embryogenesis and postembryonic development, stress responses, and tolerance mechanisms. Emphasizing the chaperone activity of plant NudC family members, crucial for mitigating stress effects and enhancing plant resilience, we highlight their potential as valuable targets for enhancing crop performance. Moreover, the structural and functional conservation of NudC proteins across species suggests their potential applications in medical research, particularly in functions related to cell division, microtubule regulation, and associated pathways. Finally, we outline future research avenues centering on the exploration of under investigated functions of NudC proteins in plants.
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Affiliation(s)
- Valya Vassileva
- Department of Molecular Biology and Genetics, Laboratory of Regulation of Gene Expression, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (M.G.); (D.T.)
| | | | | | - Kiril Mishev
- Department of Molecular Biology and Genetics, Laboratory of Regulation of Gene Expression, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (M.G.); (D.T.)
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Zaharieva A, Rusanov K, Rusanova M, Paunov M, Yordanova Z, Mantovska D, Tsacheva I, Petrova D, Mishev K, Dobrev PI, Lacek J, Filepová R, Zehirov G, Vassileva V, Mišić D, Motyka V, Chaneva G, Zhiponova M. Uncovering the Interrelation between Metabolite Profiles and Bioactivity of In Vitro- and Wild-Grown Catmint ( Nepeta nuda L.). Metabolites 2023; 13:1099. [PMID: 37887424 PMCID: PMC10609352 DOI: 10.3390/metabo13101099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/14/2023] [Accepted: 10/18/2023] [Indexed: 10/28/2023] Open
Abstract
Nepeta nuda L. is a medicinal plant enriched with secondary metabolites serving to attract pollinators and deter herbivores. Phenolics and iridoids of N. nuda have been extensively investigated because of their beneficial impacts on human health. This study explores the chemical profiles of in vitro shoots and wild-grown N. nuda plants (flowers and leaves) through metabolomic analysis utilizing gas chromatography and mass spectrometry (GC-MS). Initially, we examined the differences in the volatiles' composition in in vitro-cultivated shoots comparing them with flowers and leaves from plants growing in natural environment. The characteristic iridoid 4a-α,7-β,7a-α-nepetalactone was highly represented in shoots of in vitro plants and in flowers of plants from nature populations, whereas most of the monoterpenes were abundant in leaves of wild-grown plants. The known in vitro biological activities encompassing antioxidant, antiviral, antibacterial potentials alongside the newly assessed anti-inflammatory effects exhibited consistent associations with the total content of phenolics, reducing sugars, and the identified metabolic profiles in polar (organic acids, amino acids, alcohols, sugars, phenolics) and non-polar (fatty acids, alkanes, sterols) fractions. Phytohormonal levels were also quantified to infer the regulatory pathways governing phytochemical production. The overall dataset highlighted compounds with the potential to contribute to N. nuda bioactivity.
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Affiliation(s)
- Anna Zaharieva
- Department of Plant Physiology, Faculty of Biology, Sofia University “St. Kliment Ohridski”, 1164 Sofia, Bulgaria; (A.Z.); (Z.Y.); (D.M.); (D.P.); (G.C.)
| | - Krasimir Rusanov
- Department of Agrobiotechnology, Agrobioinstitute, Agricultural Academy, 1164 Sofia, Bulgaria; (K.R.)
| | - Mila Rusanova
- Department of Agrobiotechnology, Agrobioinstitute, Agricultural Academy, 1164 Sofia, Bulgaria; (K.R.)
| | - Momchil Paunov
- Department of Biophysics and Radiobiology, Faculty of Biology, Sofia University, 1164 Sofia, Bulgaria;
| | - Zhenya Yordanova
- Department of Plant Physiology, Faculty of Biology, Sofia University “St. Kliment Ohridski”, 1164 Sofia, Bulgaria; (A.Z.); (Z.Y.); (D.M.); (D.P.); (G.C.)
| | - Desislava Mantovska
- Department of Plant Physiology, Faculty of Biology, Sofia University “St. Kliment Ohridski”, 1164 Sofia, Bulgaria; (A.Z.); (Z.Y.); (D.M.); (D.P.); (G.C.)
| | - Ivanka Tsacheva
- Department of Biochemistry, Faculty of Biology, Sofia University, 1164 Sofia, Bulgaria;
| | - Detelina Petrova
- Department of Plant Physiology, Faculty of Biology, Sofia University “St. Kliment Ohridski”, 1164 Sofia, Bulgaria; (A.Z.); (Z.Y.); (D.M.); (D.P.); (G.C.)
| | - Kiril Mishev
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (K.M.); (G.Z.); (V.V.)
| | - Petre I. Dobrev
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.); (V.M.)
| | - Jozef Lacek
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.); (V.M.)
| | - Roberta Filepová
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.); (V.M.)
| | - Grigor Zehirov
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (K.M.); (G.Z.); (V.V.)
| | - Valya Vassileva
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (K.M.); (G.Z.); (V.V.)
| | - Danijela Mišić
- Department of Plant Physiology, Institute for Biological Research “Siniša Stanković”, National Institute of the Republic of Serbia, University of Belgrade, 11060 Belgrade, Serbia;
| | - Václav Motyka
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.); (V.M.)
| | - Ganka Chaneva
- Department of Plant Physiology, Faculty of Biology, Sofia University “St. Kliment Ohridski”, 1164 Sofia, Bulgaria; (A.Z.); (Z.Y.); (D.M.); (D.P.); (G.C.)
| | - Miroslava Zhiponova
- Department of Plant Physiology, Faculty of Biology, Sofia University “St. Kliment Ohridski”, 1164 Sofia, Bulgaria; (A.Z.); (Z.Y.); (D.M.); (D.P.); (G.C.)
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Roychowdhury A, Srivastava R, Akash, Shukla G, Zehirov G, Mishev K, Kumar R. Metabolic footprints in phosphate-starved plants. Physiol Mol Biol Plants 2023; 29:755-767. [PMID: 37363416 PMCID: PMC10284745 DOI: 10.1007/s12298-023-01319-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/26/2023] [Accepted: 05/29/2023] [Indexed: 06/28/2023]
Abstract
Plants' requirement of Phosphorus (P) as an essential macronutrient is obligatory for their normal growth and metabolism. Besides restricting plants' primary growth, P depletion affects both primary and secondary metabolism and leads to altered levels of sugars, metabolites, amino acids, and other secondary compounds. Such metabolic shifts help plants optimize their metabolism and growth under P limited conditions. Under P deprivation, both sugar levels and their mobilization change that influences the expression of Pi starvation-inducible genes. Increased sugar repartitioning from shoot to root help root growth and organic acids secretion that in turn promotes phosphate (Pi) uptake from the soil. Other metabolic changes such as lipid remodeling or P reallocation from older to younger leaves release the P from its bound forms in the cell. In this review, we summarize the metabolic footprinting of Pi-starved plants with respect to the benefits offered by such metabolic changes to intracellular Pi homeostasis.
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Affiliation(s)
- Abhishek Roychowdhury
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana 500046 India
| | - Rajat Srivastava
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana 500046 India
| | - Akash
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana 500046 India
| | - Gyanesh Shukla
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana 500046 India
| | - Grigor Zehirov
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Kiril Mishev
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Rahul Kumar
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana 500046 India
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Mishev K, Dobrev PI, Lacek J, Filepová R, Yuperlieva-Mateeva B, Kostadinova A, Hristeva T. Hormonomic Changes Driving the Negative Impact of Broomrape on Plant Host Interactions with Arbuscular Mycorrhizal Fungi. Int J Mol Sci 2021; 22:13677. [PMID: 34948474 PMCID: PMC8708155 DOI: 10.3390/ijms222413677] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 12/02/2022] Open
Abstract
Belowground interactions of plants with other organisms in the rhizosphere rely on extensive small-molecule communication. Chemical signals released from host plant roots ensure the development of beneficial arbuscular mycorrhizal (AM) fungi which in turn modulate host plant growth and stress tolerance. However, parasitic plants have adopted the capacity to sense the same signaling molecules and to trigger their own seed germination in the immediate vicinity of host roots. The contribution of AM fungi and parasitic plants to the regulation of phytohormone levels in host plant roots and root exudates remains largely obscure. Here, we studied the hormonome in the model system comprising tobacco as a host plant, Phelipanche spp. as a holoparasitic plant, and the AM fungus Rhizophagus irregularis. Co-cultivation of tobacco with broomrape and AM fungi alone or in combination led to characteristic changes in the levels of endogenous and exuded abscisic acid, indole-3-acetic acid, cytokinins, salicylic acid, and orobanchol-type strigolactones. The hormonal content in exudates of broomrape-infested mycorrhizal roots resembled that in exudates of infested non-mycorrhizal roots and differed from that observed in exudates of non-infested mycorrhizal roots. Moreover, we observed a significant reduction in AM colonization of infested tobacco plants, pointing to a dominant role of the holoparasite within the tripartite system.
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Affiliation(s)
- Kiril Mishev
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (B.Y.-M.); (A.K.)
| | - Petre I. Dobrev
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.)
| | - Jozef Lacek
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.)
| | - Roberta Filepová
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.)
| | - Bistra Yuperlieva-Mateeva
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (B.Y.-M.); (A.K.)
| | - Anelia Kostadinova
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (B.Y.-M.); (A.K.)
| | - Tsveta Hristeva
- Tobacco and Tobacco Products Institute, Agricultural Academy, 4108 Plovdiv, Bulgaria
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Vaseva II, Simova-Stoilova L, Kirova E, Mishev K, Depaepe T, Van Der Straeten D, Vassileva V. Ethylene signaling in salt-stressed Arabidopsis thaliana ein2-1 and ctr1-1 mutants - A dissection of molecular mechanisms involved in acclimation. Plant Physiol Biochem 2021; 167:999-1010. [PMID: 34592706 DOI: 10.1016/j.plaphy.2021.09.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 06/29/2021] [Revised: 09/10/2021] [Accepted: 09/23/2021] [Indexed: 06/13/2023]
Abstract
To pinpoint ethylene-mediated molecular mechanisms involved in the adaptive response to salt stress we conducted a comparative study of Arabidopsis thaliana wild type (Col-0), ethylene insensitive (ein2-1), and constitutive signaling (ctr1-1) mutant plants. Reduced germination and survival rates were observed in ein2-1 plants at increasing NaCl concentrations. By contrast, ctr1-1 mutation conferred salt stress tolerance during early vegetative development, corroborating earlier studies. Аll genotypes experienced strong stress as evidenced by the accumulation of reactive oxygen species (ROS) and increased membrane lipid peroxidation. However, the isoenzyme profiles of ROS scavenging enzymes demonstrated a higher peroxidase (POX) activity in ctr1-1 individuals under control and salt stress conditions. A markedly elevated free L-Proline (L-Pro) content was detected in the ethylene constitutive mutant. This coincided with the increased levels of Delta-1-Pyrroline-5-Carboxylate Synthase (P5CS) which is the rate-limiting enzyme from the proline biosynthetic pathway. A stabilized upregulation of a stress-induced P5CS1 splice variant was observed in the ctr1-1 background, which was not documented in the ethylene insensitive mutant ein2-1. Transcript profiling of the major SALT OVERLY SENSITIVE (SOS) pathway players (SOS1, SOS2, and SOS3) revealed altered gene expression in the organs of the ethylene signaling mutants. Overall suppressed SOS expression was observed in the ein2-1 mutants while only the SOS transcript profiles in the ctr1-1 roots were similar to the wild type. Altogether, we provide experimental evidence for ethylene-mediated molecular mechanisms implicated in the acclimation response to salt stress in Arabidopsis, which operate mainly through the regulation of free proline accumulation and enhanced ROS scavenging.
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Affiliation(s)
- Irina I Vaseva
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113, Sofia, Bulgaria.
| | - Lyudmila Simova-Stoilova
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113, Sofia, Bulgaria
| | - Elisaveta Kirova
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113, Sofia, Bulgaria
| | - Kiril Mishev
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113, Sofia, Bulgaria
| | - Thomas Depaepe
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckststraat 35, B-9000, Ghent, Belgium
| | - Dominique Van Der Straeten
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckststraat 35, B-9000, Ghent, Belgium
| | - Valya Vassileva
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113, Sofia, Bulgaria
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Vaseva II, Mishev K, Depaepe T, Vassileva V, Van Der Straeten D. The Diverse Salt-Stress Response of Arabidopsis ctr1-1 and ein2-1Ethylene Signaling Mutants Is Linked to Altered Root Auxin Homeostasis. Plants (Basel) 2021; 10:plants10030452. [PMID: 33673672 PMCID: PMC7997360 DOI: 10.3390/plants10030452] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/21/2021] [Accepted: 02/24/2021] [Indexed: 12/19/2022]
Abstract
We explored the interplay between ethylene signals and the auxin pool in roots exposed to high salinity using Arabidopsisthaliana wild-type plants (Col-0), and the ethylene-signaling mutants ctr1-1 (constitutive) and ein2-1 (insensitive). The negative effect of salt stress was less pronounced in ctr1-1 individuals, which was concomitant with augmented auxin signaling both in the ctr1-1 controls and after 100 mM NaCl treatment. The R2D2 auxin sensorallowed mapping this active auxin increase to the root epidermal cells in the late Cell Division (CDZ) and Transition Zone (TZ). In contrast, the ethylene-insensitive ein2-1 plants appeared depleted in active auxins. The involvement of ethylene/auxin crosstalk in the salt stress response was evaluated by introducing auxin reporters for local biosynthesis (pTAR2::GUS) and polar transport (pLAX3::GUS, pAUX1::AUX1-YFP, pPIN1::PIN1-GFP, pPIN2::PIN2-GFP, pPIN3::GUS) in the mutants. The constantly operating ethylene-signaling pathway in ctr1-1 was linked to increased auxin biosynthesis. This was accompanied by a steady expression of the auxin transporters evaluated by qRT-PCR and crosses with the auxin transport reporters. The results imply that the ability of ctr1-1 mutant to tolerate high salinity could be related to the altered ethylene/auxin regulatory loop manifested by a stabilized local auxin biosynthesis and transport.
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Affiliation(s)
- Irina I. Vaseva
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113 Sofia, Bulgaria; (K.M.); (V.V.)
- Correspondence: or
| | - Kiril Mishev
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113 Sofia, Bulgaria; (K.M.); (V.V.)
| | - Thomas Depaepe
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckststraat 35, B-9000 Ghent, Belgium; (T.D.); (D.V.D.S.)
| | - Valya Vassileva
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113 Sofia, Bulgaria; (K.M.); (V.V.)
| | - Dominique Van Der Straeten
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckststraat 35, B-9000 Ghent, Belgium; (T.D.); (D.V.D.S.)
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Georgiev O, Mishev K, Krasnikova M, Kitanova M, Dimitrova A, Karagyozov L. The Hordeum bulbosum 25S-18S rDNA region: comparison with Hordeum vulgare and other Triticeae. ACTA ACUST UNITED AC 2019; 74:319-328. [PMID: 31421048 DOI: 10.1515/znc-2018-0109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 07/18/2019] [Indexed: 11/15/2022]
Abstract
Hordeum vulgare and Hordeum bulbosum are two closely related barley species, which share a common H genome. H. vulgare has two nucleolar organizer regions (NORs), while the NOR of H. bulbosum is only one. We sequenced the 2.5 kb 25S-18S region in the rDNA of H. bulbosum and compared it to the same region in H. vulgare as well as to the other Triticeae. The region includes an intergenic spacer (IGS) with a number of subrepeats, a promoter, and an external transcribed spacer (5'ETS). The IGS of H. bulbosum downstream of 25S rRNA contains two 143-bp repeats and six 128-bp repeats. In contrast, the IGS in H. vulgare contains an array of seven 79-bp repeats and a varying number of 135-bp repeats. The 135-bp repeats in H. vulgare and the 128-bp repeats in H. bulbosum show similarity. Compared to H. vulgare, the 5'ETS of H. bulbosum is shorter. Additionally, the 5'ETS regions in H. bulbosum and H. vulgare diverged faster than in other Triticeae genera. Alignment of the Triticeae promoter sequences suggests that in Hordeum, as in diploid Triticum, transcription starts with guanine and not with adenine as it is in many other plants.
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Affiliation(s)
- Oleg Georgiev
- Institute of Molecular Life Sciences, University Zurich-Irchel, Winterthurer Str. 190, CH-8057 Zurich, Switzerland
| | - Kiril Mishev
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria
| | - Maria Krasnikova
- Department of Genetics, Faculty of Biology, St. Kl. Ohridsky University of Sofia, 8 Dragan Tsankov bld., 1164 Sofia, Bulgaria
| | - Meglena Kitanova
- Department of Genetics, Faculty of Biology, St. Kl. Ohridsky University of Sofia, 8 Dragan Tsankov bld., 1164 Sofia, Bulgaria
| | - Anna Dimitrova
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria, Phone: +359 2 9792677, Fax: +359 2 9785516, E-mail:
| | - Luchezar Karagyozov
- Department of Genetics, Faculty of Biology, St. Kl. Ohridsky University of Sofia, 8 Dragan Tsankov bld., 1164 Sofia, Bulgaria
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Dejonghe W, Sharma I, Denoo B, De Munck S, Lu Q, Mishev K, Bulut H, Mylle E, De Rycke R, Vasileva M, Savatin DV, Nerinckx W, Staes A, Drozdzecki A, Audenaert D, Yperman K, Madder A, Friml J, Van Damme D, Gevaert K, Haucke V, Savvides SN, Winne J, Russinova E. Disruption of endocytosis through chemical inhibition of clathrin heavy chain function. Nat Chem Biol 2019; 15:641-649. [DOI: 10.1038/s41589-019-0262-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 03/04/2019] [Indexed: 11/09/2022]
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Mishev K, Lu Q, Denoo B, Peurois F, Dejonghe W, Hullaert J, De Rycke R, Boeren S, Bretou M, De Munck S, Sharma I, Goodman K, Kalinowska K, Storme V, Nguyen LSL, Drozdzecki A, Martins S, Nerinckx W, Audenaert D, Vert G, Madder A, Otegui MS, Isono E, Savvides SN, Annaert W, De Vries S, Cherfils J, Winne J, Russinova E. Nonselective Chemical Inhibition of Sec7 Domain-Containing ARF GTPase Exchange Factors. Plant Cell 2018; 30:2573-2593. [PMID: 30018157 PMCID: PMC6241273 DOI: 10.1105/tpc.18.00145] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 06/25/2018] [Accepted: 07/17/2018] [Indexed: 05/12/2023]
Abstract
Small GTP-binding proteins from the ADP-ribosylation factor (ARF) family are important regulators of vesicle formation and cellular trafficking in all eukaryotes. ARF activation is accomplished by a protein family of guanine nucleotide exchange factors (GEFs) that contain a conserved catalytic Sec7 domain. Here, we identified and characterized Secdin, a small-molecule inhibitor of Arabidopsis thaliana ARF-GEFs. Secdin application caused aberrant retention of plasma membrane (PM) proteins in late endosomal compartments, enhanced vacuolar degradation, impaired protein recycling, and delayed secretion and endocytosis. Combined treatments with Secdin and the known ARF-GEF inhibitor Brefeldin A (BFA) prevented the BFA-induced PM stabilization of the ARF-GEF GNOM, impaired its translocation from the Golgi to the trans-Golgi network/early endosomes, and led to the formation of hybrid endomembrane compartments reminiscent of those in ARF-GEF-deficient mutants. Drug affinity-responsive target stability assays revealed that Secdin, unlike BFA, targeted all examined Arabidopsis ARF-GEFs, but that the interaction was probably not mediated by the Sec7 domain because Secdin did not interfere with the Sec7 domain-mediated ARF activation. These results show that Secdin and BFA affect their protein targets through distinct mechanisms, in turn showing the usefulness of Secdin in studies in which ARF-GEF-dependent endomembrane transport cannot be manipulated with BFA.
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Affiliation(s)
- Kiril Mishev
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Qing Lu
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Bram Denoo
- Department of Organic and Macromolecular Chemistry, Ghent University, 9000 Ghent, Belgium
| | - François Peurois
- Laboratoire de Biologie et Pharmacologie Appliquée, Centre National de la Recherche Scientifique, Ecole Normale Supérieure Paris-Saclay, 94235 Cachan, France
| | - Wim Dejonghe
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Jan Hullaert
- Department of Organic and Macromolecular Chemistry, Ghent University, 9000 Ghent, Belgium
| | - Riet De Rycke
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
- VIB BioImaging Core, 9052 Ghent, Belgium
| | - Sjef Boeren
- Laboratory of Biochemistry, Wageningen University, 6708 Wageningen, The Netherlands
| | - Marine Bretou
- Laboratory for Membrane Trafficking, VIB Center for Brain and Disease Research, KU Leuven, Department of Neurosciences, 3000 Leuven, Belgium
| | - Steven De Munck
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Department of Biochemistry and Microbiology, Ghent University, 9000 Ghent, Belgium
- Center for Inflammation Research, VIB, 9052 Ghent, Belgium
| | - Isha Sharma
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Kaija Goodman
- Laboratory of Cell and Molecular Biology and Departments of Botany and Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Kamila Kalinowska
- School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Veronique Storme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Le Son Long Nguyen
- VIB Screening Core, 9052 Ghent, Belgium
- Expertise Centre for Bioassay Development and Screening (C-BIOS), Ghent University, 9052 Ghent, Belgium
| | - Andrzej Drozdzecki
- VIB Screening Core, 9052 Ghent, Belgium
- Expertise Centre for Bioassay Development and Screening (C-BIOS), Ghent University, 9052 Ghent, Belgium
| | - Sara Martins
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Université Paris Sud, Université Paris-Saclay, Gif-sur-Yvette 91198, France
| | - Wim Nerinckx
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Department of Biochemistry and Microbiology, Ghent University, 9000 Ghent, Belgium
- Center for Medical Biotechnology, VIB, 9052 Ghent, Belgium
| | - Dominique Audenaert
- VIB Screening Core, 9052 Ghent, Belgium
- Expertise Centre for Bioassay Development and Screening (C-BIOS), Ghent University, 9052 Ghent, Belgium
| | - Grégory Vert
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Université Paris Sud, Université Paris-Saclay, Gif-sur-Yvette 91198, France
| | - Annemieke Madder
- Department of Organic and Macromolecular Chemistry, Ghent University, 9000 Ghent, Belgium
| | - Marisa S Otegui
- Laboratory of Cell and Molecular Biology and Departments of Botany and Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Erika Isono
- School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Savvas N Savvides
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Department of Biochemistry and Microbiology, Ghent University, 9000 Ghent, Belgium
- Center for Inflammation Research, VIB, 9052 Ghent, Belgium
| | - Wim Annaert
- Laboratory for Membrane Trafficking, VIB Center for Brain and Disease Research, KU Leuven, Department of Neurosciences, 3000 Leuven, Belgium
| | - Sacco De Vries
- Laboratory of Biochemistry, Wageningen University, 6708 Wageningen, The Netherlands
| | - Jacqueline Cherfils
- Laboratoire de Biologie et Pharmacologie Appliquée, Centre National de la Recherche Scientifique, Ecole Normale Supérieure Paris-Saclay, 94235 Cachan, France
| | - Johan Winne
- Department of Organic and Macromolecular Chemistry, Ghent University, 9000 Ghent, Belgium
| | - Eugenia Russinova
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
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10
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Kania U, Nodzyński T, Lu Q, Hicks GR, Nerinckx W, Mishev K, Peurois F, Cherfils J, De Rycke R, Grones P, Robert S, Russinova E, Friml J. The Inhibitor Endosidin 4 Targets SEC7 Domain-Type ARF GTPase Exchange Factors and Interferes with Subcellular Trafficking in Eukaryotes. Plant Cell 2018; 30:2553-2572. [PMID: 30018156 PMCID: PMC6241256 DOI: 10.1105/tpc.18.00127] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 06/29/2018] [Accepted: 07/17/2018] [Indexed: 05/10/2023]
Abstract
The trafficking of subcellular cargos in eukaryotic cells crucially depends on vesicle budding, a process mediated by ARF-GEFs (ADP-ribosylation factor guanine nucleotide exchange factors). In plants, ARF-GEFs play essential roles in endocytosis, vacuolar trafficking, recycling, secretion, and polar trafficking. Moreover, they are important for plant development, mainly through controlling the polar subcellular localization of PIN-FORMED transporters of the plant hormone auxin. Here, using a chemical genetics screen in Arabidopsis thaliana, we identified Endosidin 4 (ES4), an inhibitor of eukaryotic ARF-GEFs. ES4 acts similarly to and synergistically with the established ARF-GEF inhibitor Brefeldin A and has broad effects on intracellular trafficking, including endocytosis, exocytosis, and vacuolar targeting. Additionally, Arabidopsis and yeast (Saccharomyces cerevisiae) mutants defective in ARF-GEF show altered sensitivity to ES4. ES4 interferes with the activation-based membrane association of the ARF1 GTPases, but not of their mutant variants that are activated independently of ARF-GEF activity. Biochemical approaches and docking simulations confirmed that ES4 specifically targets the SEC7 domain-containing ARF-GEFs. These observations collectively identify ES4 as a chemical tool enabling the study of ARF-GEF-mediated processes, including ARF-GEF-mediated plant development.
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Affiliation(s)
- Urszula Kania
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
- Department of Plant Biotechnology and Bioinformatics, Ghent University and Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Tomasz Nodzyński
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, CZ-625 00 Brno, Czech Republic
| | - Qing Lu
- Department of Plant Biotechnology and Bioinformatics, Ghent University and Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Glenn R Hicks
- Center for Plant Cell Biology and Department of Botany and Plant Sciences, University of California, Riverside, California 92521
| | - Wim Nerinckx
- VIB-UGent Center for Medical Biotechnology, 9052 Ghent-Zwijnaarde, Belgium
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Department of Biochemistry and Microbiology, Ghent University, 9000 Ghent, Belgium
| | - Kiril Mishev
- Department of Plant Biotechnology and Bioinformatics, Ghent University and Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - François Peurois
- Laboratoire de Biologie et Pharmacologie Appliquée CNRS, Ecole Normale Supérieure Paris-Saclay, 94235 Cachan, France
| | - Jacqueline Cherfils
- Laboratoire de Biologie et Pharmacologie Appliquée CNRS, Ecole Normale Supérieure Paris-Saclay, 94235 Cachan, France
| | - Riet De Rycke
- Department of Plant Biotechnology and Bioinformatics, Ghent University and Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
- VIB BioImaging Core, 9052Ghent, Belgium
| | - Peter Grones
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden
| | - Stéphanie Robert
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden
| | - Eugenia Russinova
- Department of Plant Biotechnology and Bioinformatics, Ghent University and Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Jiří Friml
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
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11
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Dimitrova AD, Georgiev O, Mishev K, Tzvetkov S, Ananiev ED, Karagyozov L. Mapping of unmethylated sites in rDNA repeats in barley NOR deletion line. J Plant Physiol 2016; 205:97-104. [PMID: 27649325 DOI: 10.1016/j.jplph.2016.07.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 05/15/2016] [Revised: 07/20/2016] [Accepted: 07/21/2016] [Indexed: 06/06/2023]
Abstract
Extensive cytosine methylation is characteristic of plant rDNA. Evidence exists, however, that the active rRNA genes are less methylated. In this work we report on the mapping of unmethylated CCGG sites in Hordeum vulgare rDNA repeats by digestion with methylation sensitive restriction enzyme HpaII and indirect end-labeling of the generated fragments. For mapping we used genomic DNA from barley deletion line with a single NOR on chromosome 5H. This NOR is more active in order to compensate for the missing NOR 6H. The enhanced NOR 5H activity in the deletion mutant is not due to higher multiplicity of the rRNA genes or, as sequencing showed, to changes in the subunit structure of the intergenic spacer. The HpaII sites in barley rDNA are heavily methylated. Nevertheless, a fraction of the rDNA repeats is hypomethylated with unmethylated CCGG sites at various positions. One unmethylated CCGG sequence is close to the transcription start site, downstream of the 135bp subrepeats. Unmethylated sites are also present in the external transcribed spacer and in the genes coding mature rRNAs. The patterns of unmethylated sites in the barley deletion line and in lines with two NORs were compared. It is hypothesized that the occurrence of unmethylated sites on a fixed subset of rDNA repeats correlates with their transcriptional activity.
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Affiliation(s)
- Anna D Dimitrova
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria.
| | - Oleg Georgiev
- Institute of Molecular Life Sciences, University Zurich-Irchel, Winterthurer Str. 190, CH-8057 Zurich, Switzerland
| | - Kiril Mishev
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria
| | - Stefan Tzvetkov
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria
| | - Evgueni D Ananiev
- Department of Plant Physiology, Faculty of Biology, St. Kl. Ohridsky University of Sofia, 8 Dragan Tsankov bld., 1164 Sofia, Bulgaria
| | - Luchezar Karagyozov
- Department of Plant Physiology, Faculty of Biology, St. Kl. Ohridsky University of Sofia, 8 Dragan Tsankov bld., 1164 Sofia, Bulgaria
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12
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Dejonghe W, Kuenen S, Mylle E, Vasileva M, Keech O, Viotti C, Swerts J, Fendrych M, Ortiz-Morea FA, Mishev K, Delang S, Scholl S, Zarza X, Heilmann M, Kourelis J, Kasprowicz J, Nguyen LSL, Drozdzecki A, Van Houtte I, Szatmári AM, Majda M, Baisa G, Bednarek SY, Robert S, Audenaert D, Testerink C, Munnik T, Van Damme D, Heilmann I, Schumacher K, Winne J, Friml J, Verstreken P, Russinova E. Mitochondrial uncouplers inhibit clathrin-mediated endocytosis largely through cytoplasmic acidification. Nat Commun 2016; 7:11710. [PMID: 27271794 PMCID: PMC4899852 DOI: 10.1038/ncomms11710] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 04/21/2016] [Indexed: 11/27/2022] Open
Abstract
ATP production requires the establishment of an electrochemical proton gradient across the inner mitochondrial membrane. Mitochondrial uncouplers dissipate this proton gradient and disrupt numerous cellular processes, including vesicular trafficking, mainly through energy depletion. Here we show that Endosidin9 (ES9), a novel mitochondrial uncoupler, is a potent inhibitor of clathrin-mediated endocytosis (CME) in different systems and that ES9 induces inhibition of CME not because of its effect on cellular ATP, but rather due to its protonophore activity that leads to cytoplasm acidification. We show that the known tyrosine kinase inhibitor tyrphostinA23, which is routinely used to block CME, displays similar properties, thus questioning its use as a specific inhibitor of cargo recognition by the AP-2 adaptor complex via tyrosine motif-based endocytosis signals. Furthermore, we show that cytoplasm acidification dramatically affects the dynamics and recruitment of clathrin and associated adaptors, and leads to reduction of phosphatidylinositol 4,5-biphosphate from the plasma membrane. Plant cells maintain strict proton gradients over different membranes. Here, Dejonghe et al. show that several protonophores, including the known tyrosine kinase inhibitor TyrphostinA23, inhibit clathrin-mediated endocytosis by disturbing these gradients and causing cytoplasmic acidification.
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Affiliation(s)
- Wim Dejonghe
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Sabine Kuenen
- VIB Center for the Biology of Disease, Laboratory of Neuronal Communication, 3000 Leuven, Belgium.,Department for Human Genetics, and Leuven Institute for Neurodegenerative Diseases, KU Leuven, 3000 Leuven, Belgium
| | - Evelien Mylle
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Mina Vasileva
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Olivier Keech
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, 90187 Umeå, Sweden
| | - Corrado Viotti
- Department of Plant Physiology, Institute of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany
| | - Jef Swerts
- VIB Center for the Biology of Disease, Laboratory of Neuronal Communication, 3000 Leuven, Belgium.,Department for Human Genetics, and Leuven Institute for Neurodegenerative Diseases, KU Leuven, 3000 Leuven, Belgium
| | - Matyáš Fendrych
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Fausto Andres Ortiz-Morea
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Kiril Mishev
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Simon Delang
- Developmental Biology of Plants, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Stefan Scholl
- Developmental Biology of Plants, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Xavier Zarza
- Department of Plant Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1090 GE Amsterdam, The Netherlands
| | - Mareike Heilmann
- Department of Cellular Biochemistry, Institute for Biochemistry and Biotechnology, Martin-Luther-University, 06120 Halle, Germany
| | - Jiorgos Kourelis
- Department of Plant Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1090 GE Amsterdam, The Netherlands
| | - Jaroslaw Kasprowicz
- VIB Center for the Biology of Disease, Laboratory of Neuronal Communication, 3000 Leuven, Belgium.,Department for Human Genetics, and Leuven Institute for Neurodegenerative Diseases, KU Leuven, 3000 Leuven, Belgium
| | | | | | - Isabelle Van Houtte
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Anna-Mária Szatmári
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Mateusz Majda
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden
| | - Gary Baisa
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | | | - Stéphanie Robert
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden
| | | | - Christa Testerink
- Department of Plant Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1090 GE Amsterdam, The Netherlands
| | - Teun Munnik
- Department of Plant Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1090 GE Amsterdam, The Netherlands
| | - Daniël Van Damme
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Ingo Heilmann
- Department of Cellular Biochemistry, Institute for Biochemistry and Biotechnology, Martin-Luther-University, 06120 Halle, Germany
| | - Karin Schumacher
- Developmental Biology of Plants, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Johan Winne
- Laboratory for Organic Synthesis, Department of Organic and Macromolecular Chemistry, Ghent University, 9000 Gent, Belgium
| | - Jiří Friml
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Patrik Verstreken
- VIB Center for the Biology of Disease, Laboratory of Neuronal Communication, 3000 Leuven, Belgium.,Department for Human Genetics, and Leuven Institute for Neurodegenerative Diseases, KU Leuven, 3000 Leuven, Belgium
| | - Eugenia Russinova
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
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13
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Betti C, Vanhoutte I, Coutuer S, De Rycke R, Mishev K, Vuylsteke M, Aesaert S, Rombaut D, Gallardo R, De Smet F, Xu J, Van Lijsebettens M, Van Breusegem F, Inzé D, Rousseau F, Schymkowitz J, Russinova E. Sequence-Specific Protein Aggregation Generates Defined Protein Knockdowns in Plants. Plant Physiol 2016; 171:773-87. [PMID: 27208282 PMCID: PMC4902617 DOI: 10.1104/pp.16.00335] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 04/29/2016] [Indexed: 05/04/2023]
Abstract
Protein aggregation is determined by short (5-15 amino acids) aggregation-prone regions (APRs) of the polypeptide sequence that self-associate in a specific manner to form β-structured inclusions. Here, we demonstrate that the sequence specificity of APRs can be exploited to selectively knock down proteins with different localization and function in plants. Synthetic aggregation-prone peptides derived from the APRs of either the negative regulators of the brassinosteroid (BR) signaling, the glycogen synthase kinase 3/Arabidopsis SHAGGY-like kinases (GSK3/ASKs), or the starch-degrading enzyme α-glucan water dikinase were designed. Stable expression of the APRs in Arabidopsis (Arabidopsis thaliana) and maize (Zea mays) induced aggregation of the target proteins, giving rise to plants displaying constitutive BR responses and increased starch content, respectively. Overall, we show that the sequence specificity of APRs can be harnessed to generate aggregation-associated phenotypes in a targeted manner in different subcellular compartments. This study points toward the potential application of induced targeted aggregation as a useful tool to knock down protein functions in plants and, especially, to generate beneficial traits in crops.
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Affiliation(s)
- Camilla Betti
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Isabelle Vanhoutte
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Silvie Coutuer
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Riet De Rycke
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Kiril Mishev
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Marnik Vuylsteke
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Stijn Aesaert
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Debbie Rombaut
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Rodrigo Gallardo
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Frederik De Smet
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Jie Xu
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Mieke Van Lijsebettens
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Frank Van Breusegem
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Dirk Inzé
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Frederic Rousseau
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Joost Schymkowitz
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
| | - Eugenia Russinova
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium (C.B., I.V., S.C., R.D.R., K.M., S.A., D.R., M.V.L., F.V.B., D.I., E.R.);Switch Laboratory, VIB, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S.);Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven, 3000 Leuven, Belgium (R.G., F.D.S., J.X., F.R., J.S); andGnomixx, 9000 Gent, Belgium (M.V.)
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Dejonghe W, Mishev K, Russinova E. The brassinosteroid chemical toolbox. Curr Opin Plant Biol 2014; 22:48-55. [PMID: 25282585 DOI: 10.1016/j.pbi.2014.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 08/29/2014] [Accepted: 09/05/2014] [Indexed: 06/03/2023]
Abstract
Chemical biology approaches have been instrumental in understanding the mode of action of brassinosteroids, a group of plant steroid hormones essential for plant development and growth. The small molecules used for such approaches include inhibitors of biosynthetic enzymes and signaling components. Additionally, recent structural data on the brassinosteroid receptor complex together with its ligand brassinolide, the most active brassinosteroid, and knowledge on its different analogs have given us a better view on the recognition of the hormone and signaling initiation. Moreover, a fluorescently labeled brassinosteroid enabled the visualization of the receptor-ligand pair in the cell. Given the insights obtained, small molecules will continue to provide new opportunities for probing brassinosteroid biosynthesis and for unraveling the dynamic and highly interconnected signaling.
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Affiliation(s)
- Wim Dejonghe
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Kiril Mishev
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Eugenia Russinova
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
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15
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Mishev K, Dejonghe W, Russinova E. Small Molecules for Dissecting Endomembrane Trafficking: A Cross-Systems View. ACTA ACUST UNITED AC 2013; 20:475-86. [DOI: 10.1016/j.chembiol.2013.03.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 03/19/2013] [Accepted: 03/20/2013] [Indexed: 01/31/2023]
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Mishev K, Dimitrova A, Ananiev ED. Darkness affects differentially the expression of plastid-encoded genes and delays the senescence-induced down-regulation of chloroplast transcription in cotyledons of Cucurbita pepo L. (Zucchini). Z NATURFORSCH C 2011; 66:159-166. [PMID: 21630590] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In contrast to differentiated leaves, the regulatory mechanisms of chloroplast gene expression in darkened cotyledons have not been elucidated. Although some results have been reported indicating accelerated senescence in Arabidopsis upon reillumination, the capacity of cotyledons to recover after dark stress remains unclear. We analysed the effect of two-days dark stress, applied locally or at the whole-plant level, on plastid gene expression in zucchini cotyledons. Our results showed that in the dark the overall chloroplast transcription rate was much more inhibited than the nuclear run-on transcription. While the activities of the plastid-encoded RNA polymerase (PEP) and nuclear RNA polymerase II were strongly reduced, the activities of the nuclear-encoded plastid RNA polymerase (NEP) and nuclear RNA polymerase I were less affected. During recovery upon reillumination, chloroplast transcription in the cotyledons was strongly stimulated (3-fold) compared with the naturally senescing controls, suggesting delayed senescence. Northern blot and dot blot analyses of the expression of key chloroplast-encoded photosynthetic genes showed that in contrast to psbA, which remained almost unaffected, both the transcription rate and mRNA content of psaB and rbcL were substantially decreased.
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Affiliation(s)
- Kiril Mishev
- Acad. M. Popov Institute of Plant Physiology, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria
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Mishev K, Dimitrova A, Ananiev ED. Darkness Affects Differentially the Expression of Plastid-Encoded Genes and Delays the Senescence-Induced Down-Regulation of Chloroplast Transcription in Cotyledons of Cucurbita pepo L. (Zucchini). Z NATURFORSCH C 2011. [DOI: 10.5560/znc.2011.66c0159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Ananieva K, Ananiev ED, Mishev K, Georgieva K, Malbeck J, Kamínek M, Van Staden J. Methyl jasmonate is a more effective senescence-promoting factor in Cucurbita pepo (zucchini) cotyledons when compared with darkness at the early stage of senescence. J Plant Physiol 2007; 164:1179-87. [PMID: 16987568 DOI: 10.1016/j.jplph.2006.07.008] [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] [Received: 04/18/2006] [Accepted: 07/04/2006] [Indexed: 05/11/2023]
Abstract
The effects of short-term darkening and methyl jasmonate (MeJA) on cotyledon senescence were studied 24h after transfer of intact 7-day-old Cucurbita pepo (zucchini) seedlings to darkness or spraying with 100 microM MeJA. The jasmonate inhibitory effect on chlorophyll content and chloroplast transcriptional activity was stronger compared with darkness. Further, MeJA reduced the photosynthetic rate whereas darkness did not affect photosynthesis. Neither stress factor affected the photochemical quantum efficiency of photosystem II (PSII) estimated by the variable fluorescence (F(v))/maximal fluorescence (F(m)) ratio, suggesting the existence of mechanisms protecting the functional activity of PSII at earlier stages of senescence, thus making this parameter more stable compared to others used to quantify senescence. Both stress factors caused a decrease in the content of physiologically active cytokinins, especially trans-zeatin (Z), with the jasmonate effect being much more pronounced when compared to darkness. Our results indicate that MeJA is a more potent inducer of senescence in zucchini cotyledons, at least within the relatively short period of the 24h treatment. This is likely due to its stronger down-regulatory effect on the levels of physiologically active cytokinins.
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Affiliation(s)
- Kalina Ananieva
- Acad M Popov Institute of Plant Physiology, Acad G Bonchev Str, Bl 21, Sofia, Bulgaria
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Doltchinkova V, Georgieva K, Traytcheva N, Slavov C, Mishev K. Melittin-induced changes in thylakoid membranes: particle electrophoresis and light scattering study. Biophys Chem 2004; 109:387-97. [PMID: 15110936 DOI: 10.1016/j.bpc.2003.10.030] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2003] [Revised: 09/18/2003] [Accepted: 10/23/2003] [Indexed: 11/29/2022]
Abstract
Thylakoids were used as a model system to evaluate the effect of bee venom peptide melittin (Mt) on membrane surface charge. At neutral pH, thylakoid membrane surfaces carry excess negative electrical charge. Mt strongly altered the electrophoretic mobility (EPM) of 'low-salt' thylakoids and did not significantly change the EPM of 'high-salt' thylakoids. Mt increased the primary ionic-exchange processes across the 'low-salt' thylakoid membranes, while it did not affect those of 'high-salt' thylakoids. Mt decreased the proton gradient generation on the membranes at both ionic strengths, but it affected more strongly the 'high-salt' than that of 'low-salt' thylakoids. The primary photochemical activity of photosystem II, estimated by the ratio Fv/Fm, was not influenced by the low Mt concentrations. It decreased only when chloroplasts had been incubated with higher Mt concentrations and this effect was better expressed in 'low-salt' than in 'high-salt' thylakoid membranes.
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Affiliation(s)
- Virjinia Doltchinkova
- Faculty of Biology, Department of Biophysics and Radiobiology, Sofia University, 8 Dragan Tzankov Boulevard, 1164 Sofia, Bulgaria.
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