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Lee S, Kim J, Kim MS, Min CW, Kim ST, Choi SB, Lee JH, Choi D. The Phytophthora nucleolar effector Pi23226 targets host ribosome biogenesis to induce necrotrophic cell death. PLANT COMMUNICATIONS 2023; 4:100606. [PMID: 37087572 PMCID: PMC10504586 DOI: 10.1016/j.xplc.2023.100606] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 03/15/2023] [Accepted: 04/19/2023] [Indexed: 05/03/2023]
Abstract
Pathogen effectors target diverse subcellular organelles to manipulate the plant immune system. Although the nucleolus has emerged as a stress marker and several effectors are localized in the nucleolus, the roles of nucleolar-targeted effectors remain elusive. In this study, we showed that Phytophthora infestans infection of Nicotiana benthamiana results in nucleolar inflation during the transition from the biotrophic to the necrotrophic phase. Multiple P. infestans effectors were localized in the nucleolus: Pi23226 induced cell death in N. benthamiana and nucleolar inflation similar to that observed in the necrotrophic stage of infection, whereas its homolog Pi23015 and a deletion mutant (Pi23226ΔC) did not induce cell death or affect nucleolar size. RNA immunoprecipitation and individual-nucleotide-resolution UV crosslinking and immunoprecipitation sequencing analysis indicated that Pi23226 bound to the 3' end of 25S rRNA precursors, resulting in accumulation of unprocessed 27S pre-rRNAs. The nucleolar stress marker NAC082 was strongly upregulated under Pi23226-expressing conditions. Pi23226 subsequently inhibited global protein translation in host cells by interacting with ribosomes. Pi23226 enhanced P. infestans pathogenicity, indicating that Pi23226-induced ribosome malfunction and cell death were beneficial for pathogenesis in the host. Our results provide evidence for the molecular mechanism underlying RNA-binding effector activity in host ribosome biogenesis and lead to new insights into the nucleolar action of effectors in pathogenesis.
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Affiliation(s)
- Soeui Lee
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea; Plant Genomics and Breeding Institute, Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Jaehwan Kim
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea; Plant Genomics and Breeding Institute, Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Myung-Shin Kim
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea; Interdisciplinary Programs in Agricultural Genomics, College of Agriculture and Life Science, Seoul National University, Seoul 08826, Republic of Korea; Division of Bioscience and Bioinformatics, Myongji University, Yongin 449-728, Republic of Korea
| | - Cheol Woo Min
- Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 50463, Republic of Korea
| | - Sun Tae Kim
- Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 50463, Republic of Korea
| | - Sang-Bong Choi
- Division of Bioscience and Bioinformatics, Myongji University, Yongin 449-728, Republic of Korea
| | - Joo Hyun Lee
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea.
| | - Doil Choi
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea; Plant Genomics and Breeding Institute, Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Science, Seoul National University, Seoul 08826, Republic of Korea.
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Farias KS, Ferreira MM, Amaral GV, Zugaib M, Santos AS, Gomes FP, Rezende RP, Gramacho KP, Aguiar ERGR, Pirovani CP. BASIDIN as a New Protein Effector of the Phytopathogen Causing Witche's Broom Disease in Cocoa. Int J Mol Sci 2023; 24:11714. [PMID: 37511472 PMCID: PMC10380501 DOI: 10.3390/ijms241411714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
The fungus Moniliophthora perniciosa secretes protein effectors that manipulate the physiology of the host plant, but few effectors of this fungus have had their functions confirmed. We performed functional characterization of a promising candidate effector of M. perniciosa. The inoculation of rBASIDIN at 4 µmol L-1 in the mesophyll of leaflets of Solanum lycopersicum caused symptoms of shriveling within 6 h without the presence of necrosis. However, when sprayed on the plant at a concentration of 11 µmol L-1, it caused wilting symptoms only 2 h after application, followed by necrosis and cell death at 48 h. rBASIDIN applied to Theobroma cacao leaves at the same concentration caused milder symptoms. rBASIDIN caused hydrogen peroxide production in leaf tissue, damaging the leaf membrane and negatively affecting the photosynthetic rate of Solanum lycopersicum plants. Phylogenetic analysis indicated that BASIDIN has orthologs in other phytopathogenic basidiomycetes. Analysis of the transcripts revealed that BASIDIN and its orthologs are expressed in different fungal species, suggesting that this protein is differentially regulated in these basidiomycetes. Therefore, the results of applying BASIDIN allow the inference that it is an effector of the fungus M. perniciosa, with a strong potential to interfere in the defense system of the host plant.
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Affiliation(s)
- Keilane Silva Farias
- Centro de Biotecnologia e Genética, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
| | - Monaliza Macêdo Ferreira
- Centro de Biotecnologia e Genética, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
| | - Geiseane Veloso Amaral
- Centro de Biotecnologia e Genética, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
| | - Maria Zugaib
- Centro de Biotecnologia e Genética, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
| | - Ariana Silva Santos
- Centro de Biotecnologia e Genética, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
| | - Fábio Pinto Gomes
- Fisiologia Vegetal, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
| | - Rachel Passos Rezende
- Centro de Biotecnologia e Genética, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
| | - Karina Peres Gramacho
- Comissão Executiva do Plano da Lavoura Cacaueira, Centro de Pesquisas do Cacau-MAPA, Laboratório de Fitopatologia Molecular, km 22 Rodovia Ilhéus Itabuna, Ilhéus 45600-970, Bahia, Brazil
| | - Eric Roberto Guimarães Rocha Aguiar
- Centro de Biotecnologia e Genética, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
| | - Carlos Priminho Pirovani
- Centro de Biotecnologia e Genética, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km 16, Ilhéus 45662-900, Bahia, Brazil
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Müller M, Kües U, Budde KB, Gailing O. Applying molecular and genetic methods to trees and their fungal communities. Appl Microbiol Biotechnol 2023; 107:2783-2830. [PMID: 36988668 PMCID: PMC10106355 DOI: 10.1007/s00253-023-12480-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 03/05/2023] [Accepted: 03/07/2023] [Indexed: 03/30/2023]
Abstract
Forests provide invaluable economic, ecological, and social services. At the same time, they are exposed to several threats, such as fragmentation, changing climatic conditions, or increasingly destructive pests and pathogens. Trees, the inherent species of forests, cannot be viewed as isolated organisms. Manifold (micro)organisms are associated with trees playing a pivotal role in forest ecosystems. Of these organisms, fungi may have the greatest impact on the life of trees. A multitude of molecular and genetic methods are now available to investigate tree species and their associated organisms. Due to their smaller genome sizes compared to tree species, whole genomes of different fungi are routinely compared. Such studies have only recently started in forest tree species. Here, we summarize the application of molecular and genetic methods in forest conservation genetics, tree breeding, and association genetics as well as for the investigation of fungal communities and their interrelated ecological functions. These techniques provide valuable insights into the molecular basis of adaptive traits, the impacts of forest management, and changing environmental conditions on tree species and fungal communities and can enhance tree-breeding cycles due to reduced time for field testing. It becomes clear that there are multifaceted interactions among microbial species as well as between these organisms and trees. We demonstrate the versatility of the different approaches based on case studies on trees and fungi. KEY POINTS: • Current knowledge of genetic methods applied to forest trees and associated fungi. • Genomic methods are essential in conservation, breeding, management, and research. • Important role of phytobiomes for trees and their ecosystems.
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Affiliation(s)
- Markus Müller
- Forest Genetics and Forest Tree Breeding, Faculty for Forest Sciences and Forest Ecology, University of Goettingen, Büsgenweg 2, 37077, Göttingen, Germany.
- Center for Integrated Breeding Research (CiBreed), University of Goettingen, 37073, Göttingen, Germany.
| | - Ursula Kües
- Molecular Wood Biotechnology and Technical Mycology, Faculty for Forest Sciences and Forest Ecology, University of Goettingen, Büsgenweg 2, 37077, Göttingen, Germany
- Center for Molecular Biosciences (GZMB), Georg-August-University Göttingen, 37077, Göttingen, Germany
- Center of Sustainable Land Use (CBL), Georg-August-University Göttingen, 37077, Göttingen, Germany
| | - Katharina B Budde
- Forest Genetics and Forest Tree Breeding, Faculty for Forest Sciences and Forest Ecology, University of Goettingen, Büsgenweg 2, 37077, Göttingen, Germany
- Center of Sustainable Land Use (CBL), Georg-August-University Göttingen, 37077, Göttingen, Germany
| | - Oliver Gailing
- Forest Genetics and Forest Tree Breeding, Faculty for Forest Sciences and Forest Ecology, University of Goettingen, Büsgenweg 2, 37077, Göttingen, Germany
- Center for Integrated Breeding Research (CiBreed), University of Goettingen, 37073, Göttingen, Germany
- Center of Sustainable Land Use (CBL), Georg-August-University Göttingen, 37077, Göttingen, Germany
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Seo YE, Yan X, Choi D, Mang H. Phytophthora infestans RxLR Effector PITG06478 Hijacks 14-3-3 to Suppress PMA Activity Leading to Necrotrophic Cell Death. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2023; 36:150-158. [PMID: 36413345 DOI: 10.1094/mpmi-06-22-0135-r] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Pathogens often induce cell death for their successful proliferation in the host plant. Plasma membrane H+-ATPases (PMAs) are targeted by either pathogens or plant immune receptors in immune response regulation. Although PMAs play pivotal roles in host cell death, the molecular mechanism of effector-mediated regulation of PMA activity has not been described. Here, we report that the Phytophthora infestans RxLR effector PITG06478 can induce cell death in Nicotiana benthamiana but the induced cell death is inhibited by fusicoccin (FC), an irreversible PMA activator. PITG06478, which is localized at the plasma membrane, is not directly associated with the PMA but is associated with Nb14-3-3s, a PMA activator. Immunoblot analyses revealed that the interaction between PITG06478 and Nb14-3-3s was disrupted by FC. PMA activity in PITG06478-expressing plants was eventually inhibited, and cell death likely occurred because the 14-3-3 protein was hijacked. Our results further confirm the significance of PMA activity in host cell death and provide new insight into how pathogens utilize essential host components to sustain their life cycle. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Ye-Eun Seo
- Plant Immunity Research Center, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Agriculture, Forestry and Bioresources, Plant Genomics and Breeding Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Xin Yan
- Plant Immunity Research Center, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Agriculture, Forestry and Bioresources, Plant Genomics and Breeding Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Doil Choi
- Plant Immunity Research Center, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Agriculture, Forestry and Bioresources, Plant Genomics and Breeding Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hyunggon Mang
- Plant Immunity Research Center, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Southern Area Crop Science, National Institute of Crop Science (NICS), RDA, Miryang, Republic of Korea
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Wang K, Wen Z, Asiegbu FO. The dark septate endophyte Phialocephala sphaeroides suppresses conifer pathogen transcripts and promotes root growth of Norway spruce. TREE PHYSIOLOGY 2022; 42:2627-2639. [PMID: 35878416 PMCID: PMC9743008 DOI: 10.1093/treephys/tpac089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
Plant-associated microbes including dark septate endophytes (DSEs) of forest trees play diverse functional roles in host fitness including growth promotion and increased defence. However, little is known about the impact on the fungal transcriptome and metabolites during tripartite interaction involving plant host, endophyte and pathogen. To understand the transcriptional regulation of endophyte and pathogen during co-infection, Norway spruce (Picea abies) seedlings were infected with DSE Phialocephala sphaeroides, or conifer root-rot pathogen Heterobasidion parviporum, or both. Phialocephala sphaeroides showed low but stable transcripts abundance (a decrease of 40%) during interaction with Norway spruce and conifer pathogen. By contrast, H. parviporum transcripts were significantly reduced (92%) during co-infection. With RNA sequencing analysis, P. sphaeroides experienced a shift from cell growth to anti-stress and antagonistic responses, while it repressed the ability of H. parviporum to access carbohydrate nutrients by suppressing its carbohydrate/polysaccharide-degrading enzyme machinery. The pathogen on the other hand secreted cysteine peptidase to restrict free growth of P. sphaeroides. The expression of both DSE P. sphaeroides and pathogen H. parviporum genes encoding plant growth promotion products were equally detected in both dual and tripartite interaction systems. This was further supported by the presence of tryptophan-dependent indolic compound in liquid culture of P. sphaeroides. Norway spruce and Arabidopsis seedlings treated with P. sphaeroides culture filtrate exhibited auxin-like phenotypes, such as enhanced root hairs, and primary root elongation at low concentration but shortened primary root at high concentration. The results suggested that the presence of the endophyte had strong repressive or suppressive effect on H. parviporum transcripts encoding genes involved in nutrient acquisition.
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Affiliation(s)
- Kai Wang
- Corresponding authors: K.Wang (; ) and F.Asiegbu ()
| | - Zilan Wen
- Department of Forest Sciences, University of Helsinki, PO Box 27, Helsinki FIN-00014, Finland
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Shao D, Smith DL, Kabbage M, Roth MG. Effectors of Plant Necrotrophic Fungi. FRONTIERS IN PLANT SCIENCE 2021; 12:687713. [PMID: 34149788 PMCID: PMC8213389 DOI: 10.3389/fpls.2021.687713] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/03/2021] [Indexed: 05/20/2023]
Abstract
Plant diseases caused by necrotrophic fungal pathogens result in large economic losses in field crop production worldwide. Effectors are important players of plant-pathogen interaction and deployed by pathogens to facilitate plant colonization and nutrient acquisition. Compared to biotrophic and hemibiotrophic fungal pathogens, effector biology is poorly understood for necrotrophic fungal pathogens. Recent bioinformatics advances have accelerated the prediction and discovery of effectors from necrotrophic fungi, and their functional context is currently being clarified. In this review we examine effectors utilized by necrotrophic fungi and hemibiotrophic fungi in the latter stages of disease development, including plant cell death manipulation. We define "effectors" as secreted proteins and other molecules that affect plant physiology in ways that contribute to disease establishment and progression. Studying and understanding the mechanisms of necrotrophic effectors is critical for identifying avenues of genetic intervention that could lead to improved resistance to these pathogens in plants.
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Affiliation(s)
| | | | | | - Mitchell G. Roth
- Department of Plant Pathology, University of Wisconsin – Madison, Madison, WI, United States
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Liu M, Jaber E, Zeng Z, Kovalchuk A, Asiegbu FO. Physiochemical and molecular features of the necrotic lesion in the Heterobasidion-Norway spruce pathosystem. TREE PHYSIOLOGY 2021; 41:791-800. [PMID: 33105481 DOI: 10.1093/treephys/tpaa141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/03/2020] [Accepted: 10/19/2020] [Indexed: 06/11/2023]
Abstract
In the forest of Northern Hemisphere, the fungi Heterobasidion annosum (Fr.) Bref. s.l. causes severe root and stem rot diseases, dramatically reducing the wood quality of conifer trees. The hallmark of the host response during the infection process is the formation of necrotic lesions and reaction zones. To characterize physiochemical and molecular features of the necrotic lesion, we conducted artificial inoculations on Norway spruce plants at different developmental stages: seedlings, young and mature trees. The results were further compared against data available on the formation of reaction zones. Strong necrosis browning or enlarged necrotic lesions were observed in infected tissues. This was accompanied by elevated pH. However, the increased pH, around 6.0 in necrotic lesions, was not as high as that documented in reaction zones, above 7.0 as marked by the intensity of the blue colour in response to 2,6-dichlorophenol indophenol dye. Peroxidase activity increased in infected plants and RNA-seq analysis of necrotic lesions showed marked upregulation of defence-related genes. Our findings highlight similarities and differences between the reaction zone and necrotic lesion formation in response of conifer trees to biotic stress.
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Affiliation(s)
- Mengxia Liu
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, FIN-00014, Helsinki, Finland
| | - Emad Jaber
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, FIN-00014, Helsinki, Finland
| | - Zhen Zeng
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, FIN-00014, Helsinki, Finland
| | - Andriy Kovalchuk
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, FIN-00014, Helsinki, Finland
| | - Fred O Asiegbu
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, PO Box 27, FIN-00014, Helsinki, Finland
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Wen Z, Zeng Z, Ren F, Asiegbu FO. The Conifer Root and Stem Rot Pathogen ( Heterobasidion parviporum): Effectome Analysis and Roles in Interspecific Fungal Interactions. Microorganisms 2019; 7:microorganisms7120658. [PMID: 31817407 PMCID: PMC6955712 DOI: 10.3390/microorganisms7120658] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 11/26/2019] [Accepted: 12/02/2019] [Indexed: 11/16/2022] Open
Abstract
Heterobasidion parviporum Niemelä & Korhonen is an economically important basidiomycete, causing root and stem rot disease of Norway spruce (Picea abies (L.) Karst) in Northern Europe. The H. parviporum genome encodes numerous small secreted proteins, which might be of importance for interacting with mycorrhiza symbionts, endophytes, and other saprotrophs. We hypothesized that small secreted proteins from H. parviporum (HpSSPs) are involved in interspecific fungal interaction. To identify HpSSP-coding genes potentially involved, we screened the H. parviporum effectome and compared their transcriptomic profiles during fungal development and in planta tree infection. We further conducted phylogenetic analysis, and identified a subset of hypothetical proteins with nonpredicted domain or unknown function as HpSSPs candidates for further characterization. The HpSSPs candidates were selected based on high-quality sequence, cysteine residue frequency, protein size, and in planta expression. We subsequently explored their roles during in vitro interaction in paired cultures of H. parviporum with ectomycorrhizal Cortinarius gentilis, endophytic Phialocephala sphaeroides, saprotrophs (Mycena sp., Phlebiopsis gigantea, and Phanerochaete chrysosporium), respectively. The transcriptomic profile revealed that a large proportion of effector candidates was either barely expressed or highly expressed under all growth conditions. In vitro dual-culture test showed that P. sphaeroides and C. gentilis were overgrown by H. parviporum. The barrage zone formation or no physical contact observed in paired cultures with the saprotrophs suggest they had either combative interaction or antibiosis effect with H. parviporum. Several HpSSPs individuals were up- or downregulated during the nonself interactions. The results of HpSSPs gene expression patterns provide additional insights into the diverse roles of SSPs in tree infection and interspecific fungal interactions.
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Affiliation(s)
- Zilan Wen
- Faculty of Agriculture and Forestry, P. O. Box 27, Latokartanonkaari 7, University of Helsinki, 00014 Helsinki, Finland; (Z.W.); (Z.Z.); (F.R.)
| | - Zhen Zeng
- Faculty of Agriculture and Forestry, P. O. Box 27, Latokartanonkaari 7, University of Helsinki, 00014 Helsinki, Finland; (Z.W.); (Z.Z.); (F.R.)
| | - Fei Ren
- Faculty of Agriculture and Forestry, P. O. Box 27, Latokartanonkaari 7, University of Helsinki, 00014 Helsinki, Finland; (Z.W.); (Z.Z.); (F.R.)
- Experimental Center of Forestry in North China, Chinese Academy of Forestry, No. 1 Shuiza Road, Beijing 102300, China
| | - Fred O. Asiegbu
- Faculty of Agriculture and Forestry, P. O. Box 27, Latokartanonkaari 7, University of Helsinki, 00014 Helsinki, Finland; (Z.W.); (Z.Z.); (F.R.)
- Correspondence: ; Tel.: +358-294158109
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