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Wang B, Wang Y, He W, Huang M, Yu L, Cheng D, Du J, Song B, Chen H. StMLP1, as a Kunitz trypsin inhibitor, enhances potato resistance and specifically expresses in vascular bundles during Ralstonia solanacearum infection. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 116:1342-1354. [PMID: 37614094 DOI: 10.1111/tpj.16428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 07/29/2023] [Accepted: 08/10/2023] [Indexed: 08/25/2023]
Abstract
Miraculin-like proteins (MLPs), members of the Kunitz trypsin inhibitor (KTI) family that are present in various plants, have been discovered to have a role in defending plants against pathogens. In this study, we identified a gene StMLP1 in potato that belongs to the KTI family. We found that the expression of StMLP1 gradually increases during Ralstonia solanacearum (R. solanacearum) infection. We characterized the promoter of StMLP1 as an inducible promoter that can be triggered by R. solanacearum and as a tissue-specific promoter with specificity for vascular bundle expression. Our findings demonstrate that StMLP1 exhibits trypsin inhibitor activity, and that its signal peptide is essential for proper localization and function. Overexpression of StMLP1 in potato can enhance the resistance to R. solanacearum. Inhibiting the expression of StMLP1 during infection accelerated the infection by R. solanacearum to a certain extent. In addition, the RNA-seq results of the overexpression-StMLP1 lines indicated that StMLP1 was involved in potato immunity. All these findings in our study reveal that StMLP1 functions as a positive regulator that is induced and specifically expressed in vascular bundles in response to R. solanacearum infection.
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Affiliation(s)
- Bingsen Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yuqi Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Wenfeng He
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Mengshu Huang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Liu Yu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Dong Cheng
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Juan Du
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Botao Song
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Huilan Chen
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- Potato Engineering and Technology Research Center of Hubei Province, Huazhong Agricultural University, Wuhan, 430070, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China
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Ghosh D, Kokane S, Savita BK, Kumar P, Sharma AK, Ozcan A, Kokane A, Santra S. Huanglongbing Pandemic: Current Challenges and Emerging Management Strategies. PLANTS (BASEL, SWITZERLAND) 2022; 12:plants12010160. [PMID: 36616289 PMCID: PMC9824665 DOI: 10.3390/plants12010160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 05/09/2023]
Abstract
Huanglongbing (HLB, aka citrus greening), one of the most devastating diseases of citrus, has wreaked havoc on the global citrus industry in recent decades. The culprit behind such a gloomy scenario is the phloem-limited bacteria "Candidatus Liberibacter asiaticus" (CLas), which are transmitted via psyllid. To date, there are no effective long-termcommercialized control measures for HLB, making it increasingly difficult to prevent the disease spread. To combat HLB effectively, introduction of multipronged management strategies towards controlling CLas population within the phloem system is deemed necessary. This article presents a comprehensive review of up-to-date scientific information about HLB, including currently available management practices and unprecedented challenges associated with the disease control. Additionally, a triangular disease management approach has been introduced targeting pathogen, host, and vector. Pathogen-targeting approaches include (i) inhibition of important proteins of CLas, (ii) use of the most efficient antimicrobial or immunity-inducing compounds to suppress the growth of CLas, and (iii) use of tools to suppress or kill the CLas. Approaches for targeting the host include (i) improvement of the host immune system, (ii) effective use of transgenic variety to build the host's resistance against CLas, and (iii) induction of systemic acquired resistance. Strategies for targeting the vector include (i) chemical and biological control and (ii) eradication of HLB-affected trees. Finally, a hypothetical model for integrated disease management has been discussed to mitigate the HLB pandemic.
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Affiliation(s)
- Dilip Ghosh
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur 440033, India
- Correspondence: (D.G.); (A.K.S.); (S.S.)
| | - Sunil Kokane
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur 440033, India
| | - Brajesh Kumar Savita
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Pranav Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Ashwani Kumar Sharma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, India
- Correspondence: (D.G.); (A.K.S.); (S.S.)
| | - Ali Ozcan
- Vocational School of Technical Sciences, Karamanoglu Mehmetbey University, 70200 Karaman, Turkey
- Scientific and Technological Studies Application and Research Center, Karamanoglu Mehmetbey University, 70200 Karaman, Turkey
| | - Amol Kokane
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur 440033, India
| | - Swadeshmukul Santra
- Departments of Chemistry, Nano Science Technology Center, and Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL 32816, USA
- Correspondence: (D.G.); (A.K.S.); (S.S.)
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Hiwasa-Tanase K, Yano T, Kon T, Terakawa T, Ezura H. Environmental risk assessment of transgenic miraculin-accumulating tomato in a confined field trial in Japan. PLANT BIOTECHNOLOGY (TOKYO, JAPAN) 2021; 38:421-431. [PMID: 35087307 PMCID: PMC8761588 DOI: 10.5511/plantbiotechnology.21.1021a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 10/21/2021] [Indexed: 06/14/2023]
Abstract
The commercial use of genetically modified (GM) crops requires prior assessment of the risks to the environment when these crops are grown in the field or distributed. Assessments protocols vary across countries and GM crop events, but there is a common need to assess environmental biosafety. In this study, we conducted an environmental risk assessment in a confined field of GM tomato plants that can produce miraculin, a taste-altering protein that causes sour tastes to be perceived as sweet, for practical use in Japan. The evaluation was conducted for 1) competitiveness (the ability to compete with wild plants for nutrients, sunlight, and growing areas and prevent their growth) and 2) the production of toxic substances (the ability to produce substances that interfere with the habitat and growth of wild plants, animals, and microorganisms). Investigations of plant morphology and growth characteristics as well as tolerance to low temperature during early growth and overwintering for assessment endpoints related to competitiveness showed no biologically meaningful difference between GM tomato and non-GM tomato. In addition, harmful substances in plant residues and root secretions were assessed by the plow-in method, succeeding crop test and soil microflora tests, and it was determined that GM tomato does not exhibit an increase in harmful substances. Based on these results, it was concluded that GM miraculin-accumulating tomato is comparable to conventional tomato and is unlikely to have unintended adverse effects in the natural environment of Japan.
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Affiliation(s)
- Kyoko Hiwasa-Tanase
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
- Tsukuba-Plant Innovation Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tsubasa Yano
- Inplanta Innovations, Inc., 4-5-11 Namamugi, Tsurumi-ku, Yokohama, Kanagawa 230-0052, Japan
| | - Tatsuya Kon
- Inplanta Innovations, Inc., 4-5-11 Namamugi, Tsurumi-ku, Yokohama, Kanagawa 230-0052, Japan
| | - Teruhiko Terakawa
- Inplanta Innovations, Inc., 4-5-11 Namamugi, Tsurumi-ku, Yokohama, Kanagawa 230-0052, Japan
| | - Hiroshi Ezura
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
- Tsukuba-Plant Innovation Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
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Okubo S, Terauchi K, Okada S, Saito Y, Yamaura T, Misaka T, Nakajima KI, Abe K, Asakura T. De novo transcriptome analysis and comparative expression profiling of genes associated with the taste-modifying protein neoculin in Curculigo latifolia and Curculigo capitulata fruits. BMC Genomics 2021; 22:347. [PMID: 33985426 PMCID: PMC8120819 DOI: 10.1186/s12864-021-07674-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 05/05/2021] [Indexed: 11/29/2022] Open
Abstract
Background Curculigo latifolia is a perennial plant endogenous to Southeast Asia whose fruits contain the taste-modifying protein neoculin, which binds to sweet receptors and makes sour fruits taste sweet. Although similar to snowdrop (Galanthus nivalis) agglutinin (GNA), which contains mannose-binding sites in its sequence and 3D structure, neoculin lacks such sites and has no lectin activity. Whether the fruits of C. latifolia and other Curculigo plants contain neoculin and/or GNA family members was unclear. Results Through de novo RNA-seq assembly of the fruits of C. latifolia and the related C. capitulata and detailed analysis of the expression patterns of neoculin and neoculin-like genes in both species, we assembled 85,697 transcripts from C. latifolia and 76,775 from C. capitulata using Trinity and annotated them using public databases. We identified 70,371 unigenes in C. latifolia and 63,704 in C. capitulata. In total, 38.6% of unigenes from C. latifolia and 42.6% from C. capitulata shared high similarity between the two species. We identified ten neoculin-related transcripts in C. latifolia and 15 in C. capitulata, encoding both the basic and acidic subunits of neoculin in both plants. We aligned these 25 transcripts and generated a phylogenetic tree. Many orthologs in the two species shared high similarity, despite the low number of common genes, suggesting that these genes likely existed before the two species diverged. The relative expression levels of these genes differed considerably between the two species: the transcripts per million (TPM) values of neoculin genes were 60 times higher in C. latifolia than in C. capitulata, whereas those of GNA family members were 15,000 times lower in C. latifolia than in C. capitulata. Conclusions The genetic diversity of neoculin-related genes strongly suggests that neoculin genes underwent duplication during evolution. The marked differences in their expression profiles between C. latifolia and C. capitulata may be due to mutations in regions involved in transcriptional regulation. Comprehensive analysis of the genes expressed in the fruits of these two Curculigo species helped elucidate the origin of neoculin at the molecular level. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07674-3.
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Affiliation(s)
- Satoshi Okubo
- The Yamashina Botanical Research Institute, Nippon Shinyaku Co., Ltd., Oyake Sakanotsuji-cho 39, Yamashina-ku, Kyoto, 607-8182, Japan
| | - Kaede Terauchi
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Shinji Okada
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Yoshikazu Saito
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Takao Yamaura
- The Yamashina Botanical Research Institute, Nippon Shinyaku Co., Ltd., Oyake Sakanotsuji-cho 39, Yamashina-ku, Kyoto, 607-8182, Japan
| | - Takumi Misaka
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Ken-Ichiro Nakajima
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.,Present address: Division of Endocrinology and Metabolism, National Institute for Physiological Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan
| | - Keiko Abe
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.,Kanagawa Institute of Industrial Science and Technology (KISTEC), 3-25-13 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-0821, Japan
| | - Tomiko Asakura
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
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Sun Y, Zhang L, Folimonova SY. Citrus miraculin-like protein hijacks a viral movement-related p33 protein and induces cellular oxidative stress in defence against Citrus tristeza virus. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:977-991. [PMID: 33283396 PMCID: PMC8131049 DOI: 10.1111/pbi.13523] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 10/26/2020] [Accepted: 11/30/2020] [Indexed: 05/16/2023]
Abstract
To defend against pathogens, plants have developed a complex immune system, which recognizes the pathogen effectors and mounts defence responses. In this study, the p33 protein of Citrus tristeza virus (CTV), a viral membrane-associated effector, was used as a molecular bait to explore virus interactions with host immunity. We discovered that Citrus macrophylla miraculin-like protein 2 (CmMLP2), a member of the soybean Kunitz-type trypsin inhibitor family, targets the viral p33 protein. The expression of CmMLP2 was up-regulated by p33 in the citrus phloem-associated cells. Knock-down of the MLP2 expression in citrus plants resulted in a higher virus accumulation, while the overexpression of CmMLP2 reduced the infectivity of CTV in the plant hosts. Further investigation revealed that, on the one hand, binding of CmMLP2 interrupts the cellular distribution of p33 whose proper function is necessary for the effective virus movement throughout the host. On the other hand, the ability of CmMLP2 to reorganize the endomembrane system, amalgamating the endoplasmic reticulum and the Golgi apparatus, induces cellular stress and accumulation of the reactive oxygen species, which inhibits the replication of CTV. Altogether, our data suggest that CmMLP2 employs a two-way strategy in defence against CTV infection.
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Affiliation(s)
- Yong‐Duo Sun
- Department of Plant PathologyUniversity of FloridaGainesvilleFLUSA
- Plant Molecular and Cellular Biology ProgramUniversity of FloridaGainesvilleFLUSA
| | - Lei Zhang
- Department of Plant PathologyUniversity of FloridaGainesvilleFLUSA
- Present address:
College of Horticulture and Plant ProtectionInner Mongolia Agricultural UniversityHohhot010018China
| | - Svetlana Y. Folimonova
- Department of Plant PathologyUniversity of FloridaGainesvilleFLUSA
- Plant Molecular and Cellular Biology ProgramUniversity of FloridaGainesvilleFLUSA
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6
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Fofana B, Somalraju A, Fillmore S, Zaidi M, Main D, Ghose K. Comparative transcriptome expression analysis in susceptible and resistant potato (Solanum tuberosum) cultivars to common scab (Streptomyces scabies) revealed immune priming responses in the incompatible interaction. PLoS One 2020; 15:e0235018. [PMID: 32673321 PMCID: PMC7365407 DOI: 10.1371/journal.pone.0235018] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/05/2020] [Indexed: 11/20/2022] Open
Abstract
Common scab disease in potato has become a widespread issue in major potato production areas, leading to increasing economic losses. Varietal resistance is seen as a viable and long-term scab management strategy. However, the genes and mechanisms of varietal resistance are unknown. In the current study, a comparative RNA transcriptome sequencing and differential gene signaling and priming sensitization studies were conducted in two potato cultivars that differ by their response to common scab (Streptomyces scabies), for unraveling the genes and pathways potentially involved in resistance within this pathosystem. We report on a consistent and contrasted gene expression pattern from 1,064 annotated genes differentiating a resistant (Hindenburg) and a susceptible (Green Mountain) cultivars, and identified a set of 273 co-regulated differentially expressed genes in 34 pathways that more likely reflect the genetic differences of the cultivars and metabolic mechanisms involved in the scab pathogenesis and resistance. The data suggest that comparative transcriptomic phenotyping can be used to predict scab lesion phenotype in breeding lines using mature potato tuber. The study also showed that the resistant cultivar, Hindenburg, has developed and maintained a capacity to sense and prime itself for persistent response to scab disease over time, and suggests an immune priming reaction as a mechanism for induced-resistance in scab resistant potato cultivars. The set of genes identified, described, and discussed in the study paves the foundation for detailed characterizations towards tailoring and designing procedures for targeted gene knockout through gene editing and phenotypic evaluation.
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Affiliation(s)
- Bourlaye Fofana
- Charlottetown Research and Development Centre, Agriculture and Agri-Food Canada, Charlottetown, Prince Edward Island, Canada
- * E-mail:
| | - Ashok Somalraju
- Charlottetown Research and Development Centre, Agriculture and Agri-Food Canada, Charlottetown, Prince Edward Island, Canada
| | - Sherry Fillmore
- Kentville Research and Development Centre, Agriculture and Agri-Food Canada, Kentville, Nova Scotia, Canada
| | - Mohsin Zaidi
- Charlottetown Research and Development Centre, Agriculture and Agri-Food Canada, Charlottetown, Prince Edward Island, Canada
| | - David Main
- Charlottetown Research and Development Centre, Agriculture and Agri-Food Canada, Charlottetown, Prince Edward Island, Canada
| | - Kaushik Ghose
- Department of Plant and Soil Science, Texas Tech University, Lubbock, Texas, United States of America
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7
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Cheng L, Wang D, Wang Y, Xue H, Zhang F. An integrative overview of physiological and proteomic changes of cytokinin-induced potato (Solanum tuberosum L.) tuber development in vitro. PHYSIOLOGIA PLANTARUM 2020; 168:675-693. [PMID: 31343748 DOI: 10.1111/ppl.13014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/21/2019] [Accepted: 07/22/2019] [Indexed: 05/24/2023]
Abstract
Potato tuberization is a complicated biological process regulated by multiple phytohormones, in particular cytokinins (CKs). The information available on the molecular mechanisms regulating tuber development by CKs remains largely unclear. Physiological results initially indicated that low 6-benzylaminopurine (BAP) concentration (3 mg l-1 ) advanced the tuberization beginning time and promoted tuber formation. A comparative proteomics approach was applied to investigate the proteome change of tuber development by two-dimensional gel electrophoresis in vitro, subjected to exogenous BAP treatments (0, 3, 6 and 13 mg l-1 ). Quantitative image analysis showed a total of 83 protein spots with significantly altered abundance (>2.5-fold, P < 0.05), and 55 differentially abundant proteins were identified by MALDI-TOF/TOF MS. Among these proteins, 22 proteins exhibited up-regulation with the increase of exogenous BAP concentration, and 31 proteins were upregulated at 3 mg l-1 BAP whereas being downregulated at higher BAP concentrations. These proteins were involved in metabolism and bioenergy, storage, redox homeostasis, cell defense and rescue, transcription and translation, chaperones, signaling and transport. The favorable effects of low BAP concentrations on tuber development were found in various cellular processes, mainly including the stimulation of starch and storage protein accumulation, the enhancement of the glycolysis pathway and ATP synthesis, the cellular homeostasis maintenance, the activation of pathogen defense, the higher efficiency of transcription and translation, as well as the enhanced metabolite transport. However, higher BAP concentration, especially 13 mg l-1 , showed disadvantageous effects. The proposed hypothetical model would explain the interaction of these proteins associated with CK-induced tuber development in vitro.
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Affiliation(s)
- Lixiang Cheng
- Gansu Provincial Key Laboratory of Aridland Crop Science, College of Agronomy, Gansu Key Laboratory of Crop Improvement and Germplasm Enhancement, Gansu Agricultural University, Lanzhou, China
| | - Dongxia Wang
- Gansu Provincial Key Laboratory of Aridland Crop Science, College of Agronomy, Gansu Key Laboratory of Crop Improvement and Germplasm Enhancement, Gansu Agricultural University, Lanzhou, China
| | - Yuping Wang
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| | - Hongwei Xue
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Feng Zhang
- Gansu Provincial Key Laboratory of Aridland Crop Science, College of Agronomy, Gansu Key Laboratory of Crop Improvement and Germplasm Enhancement, Gansu Agricultural University, Lanzhou, China
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8
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Chin EL, Ramsey JS, Mishchuk DO, Saha S, Foster E, Chavez JD, Howe K, Zhong X, Polek M, Godfrey KE, Mueller LA, Bruce JE, Heck M, Slupsky CM. Longitudinal Transcriptomic, Proteomic, and Metabolomic Analyses of Citrus sinensis (L.) Osbeck Graft-Inoculated with " Candidatus Liberibacter asiaticus". J Proteome Res 2020; 19:719-732. [PMID: 31885275 DOI: 10.1021/acs.jproteome.9b00616] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
"Candidatus Liberibacter asiaticus" (CLas) is the bacterium associated with the citrus disease Huanglongbing (HLB). Current CLas detection methods are unreliable during presymptomatic infection, and understanding CLas pathogenicity to help develop new detection techniques is challenging because CLas has yet to be isolated in pure culture. To understand how CLas affects citrus metabolism and whether infected plants produce systemic signals that can be used to develop improved detection techniques, leaves from Washington Navel orange (Citrus sinensis (L.) Osbeck) plants were graft-inoculated with CLas and longitudinally studied using transcriptomics (RNA sequencing), proteomics (liquid chromatography-tandem mass spectrometry), and metabolomics (proton nuclear magnetic resonance). Photosynthesis gene expression and protein levels were lower in infected plants compared to controls during late infection, and lower levels of photosynthesis proteins were identified as early as 8 weeks post-grafting. These changes coordinated with higher sugar concentrations, which have been shown to accumulate during HLB. Cell wall modification and degradation gene expression and proteins were higher in infected plants during late infection. Changes in gene expression and proteins related to plant defense were observed in infected plants as early as 8 weeks post-grafting. These results reveal coordinated changes in greenhouse navel leaves during CLas infection at the transcript, protein, and metabolite levels, which can inform of biomarkers of early infection.
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Affiliation(s)
- Elizabeth L Chin
- Department of Food Science and Technology , University of California, Davis , Davis , California 95616 , United States
| | - John S Ramsey
- Emerging Pests and Pathogens Research Unit, Robert W. Holley Center for Agriculture and Health , USDA Agricultural Research Service , Ithaca , New York 14853 , United States.,Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States
| | - Darya O Mishchuk
- Department of Food Science and Technology , University of California, Davis , Davis , California 95616 , United States
| | - Surya Saha
- Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States
| | - Elizabeth Foster
- Contained Research Facility , University of California, Davis , Davis , California 95616 , United States
| | - Juan D Chavez
- Department of Genome Sciences , University of Washington , Seattle , Washington 98195 , United States
| | - Kevin Howe
- Emerging Pests and Pathogens Research Unit, Robert W. Holley Center for Agriculture and Health , USDA Agricultural Research Service , Ithaca , New York 14853 , United States.,Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States
| | - Xuefei Zhong
- Department of Genome Sciences , University of Washington , Seattle , Washington 98195 , United States
| | - MaryLou Polek
- National Clonal Germplasm Repository for Citrus & Dates , Riverside , California 92507 , United States
| | - Kris E Godfrey
- Contained Research Facility , University of California, Davis , Davis , California 95616 , United States
| | - Lukas A Mueller
- Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States
| | - James E Bruce
- Department of Genome Sciences , University of Washington , Seattle , Washington 98195 , United States
| | - Michelle Heck
- Emerging Pests and Pathogens Research Unit, Robert W. Holley Center for Agriculture and Health , USDA Agricultural Research Service , Ithaca , New York 14853 , United States.,Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States.,Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science , Cornell University , Ithaca , New York 14853 , United States
| | - Carolyn M Slupsky
- Department of Food Science and Technology , University of California, Davis , Davis , California 95616 , United States
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9
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Ohkura SI, Hori M, Saitoh K, Okuzawa T, Okamoto I, Furukawa N, Shimizu-Ibuka A. Structural and functional analysis of miraculin-like protein from Vitis vinifera. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:1125-1130. [PMID: 30282610 DOI: 10.1016/j.bbapap.2018.08.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 08/17/2018] [Accepted: 08/24/2018] [Indexed: 11/28/2022]
Abstract
The so-called miraculin-like proteins (MLPs) are homologous to miraculin, a homodimeric protein with taste-modifying activity that converts sourness into sweetness. The identity between MLPs and miraculin generally ranges from 30% to 55%, and both MLPs and miraculin are categorized into the Kunitz-type soybean trypsin inhibitor (STI) family. MLP from grape (Vitis vinifera; vvMLP) exhibits significant homology to miraculin (61% identity), suggesting that vvMLP possesses miraculin-like properties. The results of size-exclusion chromatography and sensory analysis illustrated that vvMLP exists as a monomer in solution with no detectable taste-modifying activity. Crystal structure determination revealed that vvMLP exists as a β-trefoil fold, similarly as other MLPs and Kunitz-type protein inhibitors. The conformation of the loops, including the so-called reactive loop in the STI family, was substantially different between vvMLP and STI. Recombinant vvMLP had inhibitory activity against trypsin (Ki = 13.7 μM), indicating that the protein can act as a moderate trypsin inhibitor.
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Affiliation(s)
- So-Ichiro Ohkura
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan
| | - Misaho Hori
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan
| | - Kazuki Saitoh
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan
| | - Takumi Okuzawa
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan
| | - Ikuko Okamoto
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan
| | - Nayuta Furukawa
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan
| | - Akiko Shimizu-Ibuka
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan.
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10
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Gupta R, Lee SJ, Min CW, Kim SW, Park KH, Bae DW, Lee BW, Agrawal GK, Rakwal R, Kim ST. Coupling of gel-based 2-DE and 1-DE shotgun proteomics approaches to dig deep into the leaf senescence proteome of Glycine max. J Proteomics 2016; 148:65-74. [PMID: 27474340 DOI: 10.1016/j.jprot.2016.07.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 07/19/2016] [Accepted: 07/22/2016] [Indexed: 11/23/2022]
Abstract
UNLABELLED Leaf senescence is the last stage of leaf development that re-mobilizes nutrients from the source to sink. Here, we have utilized the soybean as a model system to unravel senescence-associated proteins (SAPs). A comparative proteomics approach was used at two contrasting stages of leaf development, namely mature (R3) and senescent (R7). Selection criteria for these two stages were the contrasting differences in their biochemical parameters - chlorophyll, carotenoids and malondialdehyde contents. Proteome analysis involved subjecting the total leaf proteins to 15% poly-ethylene glycol (PEG) pre-fractional method to enrich the low-abundance proteins (LAPs) and their analyses by gel-based 2-DE and 1-DE shotgun proteomics approaches. 2-DE profiling of PEG-supernatant and -pellet fractions detected 153 differential spots between R3 and R7 stages, of which 102 proteins were identified. In parallel, 1-DE shotgun proteomics approach identified 598 and 534 proteins in supernatant and pellet fractions of R3 and R7 stages, respectively. MapMan and Gene Ontology analyses showed increased abundance and/or specific accumulation of proteins related to jasmonic acid biosynthesis and defense, while proteins associated with photosynthesis and ROS-detoxification were decreased during leaf senescence. These findings and the generated datasets further our understanding on leaf senescence at protein level, providing a resource for the scientific community. BIOLOGICAL SIGNIFICANCE Leaf senescence is a major biological event in the life cycle of plants that leads to the recycling of nutrients. However, the molecular mechanisms underlying leaf senescence still remain poorly understood. Here, we used a combination of gel-based 2-DE and 1-DE shotgun proteomics approaches to dig deeper into the leaf senescence proteome using soybean leaf as a model experimental material. For the identification of low-abundance proteins, polyethylene glycol (PEG) fractionation was employed and both PEG-supernatant and -pellet fractions were utilized for 2-DE and shotgun proteomic analysis. A total of 1234 (102 from 2-DE and 1132 from 1-DE shotgun proteome analysis) proteins were identified which were functionally annotated using GO and MapMan bioinformatics tools. Our results also emphasize the role of jasmonic acid in soybean leaf senescence.
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Affiliation(s)
- Ravi Gupta
- Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 627-707, Republic of Korea
| | - Su Ji Lee
- Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 627-707, Republic of Korea
| | - Cheol Woo Min
- Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 627-707, Republic of Korea
| | - So Wun Kim
- Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 627-707, Republic of Korea
| | - Ki-Hun Park
- Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Dong-Won Bae
- Center for Research Facilities, Gyeongsang National University, Jinju, Republic of Korea
| | - Byong Won Lee
- Department of Functional Crops, National Institute of Crop Science (NICS), Rural Development Administration (RDA), Miryang 627-803, Republic of Korea
| | - Ganesh Kumar Agrawal
- Research Laboratory for Biotechnology and Biochemistry (RLABB), GPO Box 13265, Kathmandu, Nepal; GRADE Academy Private Limited, Adarsh Nagar-13, Birgunj, Nepal
| | - Randeep Rakwal
- Research Laboratory for Biotechnology and Biochemistry (RLABB), GPO Box 13265, Kathmandu, Nepal; GRADE Academy Private Limited, Adarsh Nagar-13, Birgunj, Nepal; Faculty of Health and Sport Sciences and Tsukuba International Academy for Sport Studies (TIAS), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan; Global Research Center for Innovative Life Science, Peptide Drug Innovation, School of Pharmacy and Pharmaceutical Sciences, Hoshi University, 4-41 Ebara 2-chome, Shinagawa, Tokyo 142-8501, Japan
| | - Sun Tae Kim
- Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 627-707, Republic of Korea.
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11
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Dees MW, Lysøe E, Alsheikh M, Davik J, Brurberg MB. Resistance to Streptomyces turgidiscabies in potato involves an early and sustained transcriptional reprogramming at initial stages of tuber formation. MOLECULAR PLANT PATHOLOGY 2016; 17:703-13. [PMID: 26416294 PMCID: PMC6638500 DOI: 10.1111/mpp.12323] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Common scab, caused by species from the bacterial genus Streptomyces, is an important disease of potato (Solanum tuberosum) crops worldwide. Early tuberization is a critical period for pathogen infection; hence, studies of host gene expression responses during this developmental stage can be important to expand our understanding of the infection process and to identify putative resistance genes. In an infection experiment with the highly susceptible potato cultivar Saturna and the relatively resistant cultivar Beate, transcription profiles were obtained by RNA sequencing at two developmental stages: the early hook stage and the early tuber formation stage. Our results indicate that 'Beate' mounts an early and sustained response to infection by S. turgidiscabies, whereas the defence response by 'Saturna' ceases before the early tuber formation stage. Most pronounced were the putative candidate defence-associated genes uniquely expressed in 'Beate'. We observed an increase in alternative splicing on pathogen infection at the early hook stage for both cultivars. A significant down-regulation of genes involved in the highly energy-demanding process of ribosome biogenesis was observed for the infected 'Beate' plants at the early hook stage, which may indicate an allocation of resources that favours the expression of defence-related genes.
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Affiliation(s)
- Merete Wiken Dees
- NIBIO, The Norwegian Institute of Bioeconomy Research, 1430, Ås, Norway
| | - Erik Lysøe
- NIBIO, The Norwegian Institute of Bioeconomy Research, 1430, Ås, Norway
| | - Muath Alsheikh
- Graminor Breeding Ltd, 2322, Ridabu, Norway
- Department of Plant Sciences, Norwegian University of Life Sciences, 1430, Ås, Norway
| | - Jahn Davik
- NIBIO, The Norwegian Institute of Bioeconomy Research, 1430, Ås, Norway
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12
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Cabeza RA, Liese R, Lingner A, von Stieglitz I, Neumann J, Salinas-Riester G, Pommerenke C, Dittert K, Schulze J. RNA-seq transcriptome profiling reveals that Medicago truncatula nodules acclimate N₂ fixation before emerging P deficiency reaches the nodules. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:6035-48. [PMID: 25151618 PMCID: PMC4203135 DOI: 10.1093/jxb/eru341] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Legume nodules are plant tissues with an exceptionally high concentration of phosphorus (P), which, when there is scarcity of P, is preferentially maintained there rather than being allocated to other plant organs. The hypothesis of this study was that nodules are affected before the P concentration in the organ declines during whole-plant P depletion. Nitrogen (N₂) fixation and P concentration in various organs were monitored during a whole-plant P-depletion process in Medicago truncatula. Nodule gene expression was profiled through RNA-seq at day 5 of P depletion. Until that point in time P concentration in leaves reached a lower threshold but was maintained in nodules. N₂-fixation activity per plant diverged from that of fully nourished plants beginning at day 5 of the P-depletion process, primarily because fewer nodules were being formed, while the activity of the existing nodules was maintained for as long as two weeks into P depletion. RNA-seq revealed nodule acclimation on a molecular level with a total of 1140 differentially expressed genes. Numerous genes for P remobilization from organic structures were increasingly expressed. Various genes involved in nodule malate formation were upregulated, while genes involved in fermentation were downregulated. The fact that nodule formation was strongly repressed with the onset of P deficiency is reflected in the differential expression of various genes involved in nodulation. It is concluded that plants follow a strategy to maintain N₂ fixation and viable leaf tissue as long as possible during whole-plant P depletion to maintain their ability to react to emerging new P sources (e.g. through active P acquisition by roots).
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Affiliation(s)
- Ricardo A Cabeza
- Department of Crop Science, Section for Plant Nutrition and Crop Physiology, Faculty of Agriculture, University of Goettingen, Carl-Sprengel-Weg 1, 37075 Goettingen, Germany
| | - Rebecca Liese
- Department of Crop Science, Section for Plant Nutrition and Crop Physiology, Faculty of Agriculture, University of Goettingen, Carl-Sprengel-Weg 1, 37075 Goettingen, Germany
| | - Annika Lingner
- Department of Crop Science, Section for Plant Nutrition and Crop Physiology, Faculty of Agriculture, University of Goettingen, Carl-Sprengel-Weg 1, 37075 Goettingen, Germany
| | - Ilsabe von Stieglitz
- Department of Crop Science, Section for Plant Nutrition and Crop Physiology, Faculty of Agriculture, University of Goettingen, Carl-Sprengel-Weg 1, 37075 Goettingen, Germany
| | - Janice Neumann
- Department of Crop Science, Section for Plant Nutrition and Crop Physiology, Faculty of Agriculture, University of Goettingen, Carl-Sprengel-Weg 1, 37075 Goettingen, Germany
| | - Gabriela Salinas-Riester
- Department of Developmental Biochemistry, DNA Microarray and Deep-Sequencing Facility, Faculty of Medicine, University of Goettingen, Justus-von-Liebig-Weg 11, 37077 Goettingen, Germany
| | - Claudia Pommerenke
- Department of Developmental Biochemistry, DNA Microarray and Deep-Sequencing Facility, Faculty of Medicine, University of Goettingen, Justus-von-Liebig-Weg 11, 37077 Goettingen, Germany
| | - Klaus Dittert
- Department of Crop Science, Section for Plant Nutrition and Crop Physiology, Faculty of Agriculture, University of Goettingen, Carl-Sprengel-Weg 1, 37075 Goettingen, Germany
| | - Joachim Schulze
- Department of Crop Science, Section for Plant Nutrition and Crop Physiology, Faculty of Agriculture, University of Goettingen, Carl-Sprengel-Weg 1, 37075 Goettingen, Germany
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Botelho-Júnior S, Machado OLT, Fernandes KVS, Lemos FJA, Perdizio VA, Oliveira AEA, Monteiro LR, Filho ML, Jacinto T. Defense response in non-genomic model species: methyl jasmonate exposure reveals the passion fruit leaves' ability to assemble a cocktail of functionally diversified Kunitz-type trypsin inhibitors and recruit two of them against papain. PLANTA 2014; 240:345-56. [PMID: 24849173 DOI: 10.1007/s00425-014-2085-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 04/17/2014] [Indexed: 05/13/2023]
Abstract
Multiplicity of protease inhibitors induced by predators may increase the understanding of a plant's intelligent behavior toward environmental challenges. Information about defense mechanisms of non-genomic model plant passion fruit (Passiflora edulis Sims) in response to predator attack is still limited. Here, via biochemical approaches, we showed its flexibility to build-up a broad repertoire of potent Kunitz-type trypsin inhibitors (KTIs) in response to methyl jasmonate. Seven inhibitors (20-25 kDa) were purified from exposed leaves by chromatographic techniques. Interestingly, the KTIs possessed truncated Kunitz motif in their N-terminus and some of them also presented non-consensus residues. Gelatin-Native-PAGE established multiple isoforms for each inhibitor. Significant differences regarding inhibitors' activity toward trypsin and chymotrypsin were observed, indicating functional polymorphism. Despite its rarity, two of them also inhibited papain, and such bifunctionality suggests a recruiting process onto another mechanistic class of target protease (cysteine-type). All inhibitors acted strongly on midgut proteases from sugarcane borer, Diatraea saccharalis (a lepidopteran insect) while in vivo assays supported their insecticide properties. Moreover, the bifunctional inhibitors displayed activity toward midgut proteases from cowpea weevil, Callosobruchus maculatus (a coleopteran insect). Unexpectedly, all inhibitors were highly effective against midgut proteases from Aedes aegypti a dipteran insect (vector of neglected tropical diseases) opening new avenues for plant-derived PIs for vector control-oriented research. Our results reflect the KTIs' complexities in passion fruit which could be wisely exploited by influencing plant defense conditions. Therefore, the potential of passion fruit as source of bioactive compounds with diversified biotechnological application was strengthened.
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Affiliation(s)
- Sylvio Botelho-Júnior
- Laboratório de Biotecnologia, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ, 28013-600, Brazil
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14
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Selvakumar P, Sharma N, Tomar PPS, Kumar P, Sharma AK. Structural insights into the aggregation behavior of Murraya koenigii miraculin-like protein below pH 7.5. Proteins 2013; 82:830-40. [PMID: 24265134 DOI: 10.1002/prot.24461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 10/03/2013] [Accepted: 10/21/2013] [Indexed: 11/07/2022]
Abstract
Murraya koenigii miraculin-like protein (MKMLP) gradually precipitates below pH 7.5. Here, we explore the basis for this aggregation by identifying the aggregation-prone regions via comparative analysis of crystal structures acquired at several pH values. The prediction of aggregation-prone regions showed the presence of four short peptides either in beta sheets or loops on surface of the protein. These peptides were distributed in two patches far apart on the surface. Comparison of crystal structures of MKMLP, determined at 2.2 Å resolution in pH 7.0 and 4.6 in the present study and determined at 2.9 Å in pH 8.0 in an earlier reported study, reveal subtle conformational differences resulting in gradual exposure of aggregation-prone regions. As the pH is lowered, there are alterations in ionic interactions within the protein interactions of the chain with water molecules and exposure of hydrophobic residues. The analysis of symmetry-related molecular interfaces involving one patch revealed shortening of nonpolar intermolecular contacts as the pH decreased. In particular, a decrease in the intermolecular distance between Trp103 of the aggregation-prone peptide WFITTG (103-108) unique to MLPs was observed. These results demonstrated that aggregation occurs due to the cumulative effect of the changes in interactions in two aggregation-prone defined regions.
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Affiliation(s)
- Purushotham Selvakumar
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, 247 667, India
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15
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Picone D, Temussi PA. Dissimilar sweet proteins from plants: oddities or normal components? PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2012; 195:135-142. [PMID: 22921007 DOI: 10.1016/j.plantsci.2012.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Revised: 06/30/2012] [Accepted: 07/02/2012] [Indexed: 06/01/2023]
Abstract
The fruits of a few tropical plants contain intensely sweet proteins. Their common property points to a protein family. Generally, proteins belonging to the same family share similar folds, similar sequences and, at least in part, similar function but sweet proteins constitute an exception to this rule. Apart from sharing the rather unusual taste function, they show no obvious similarities either in their sequences or in three-dimensional structures. In this review we describe the nature, structure and mechanism of action of the best known sweet tasting proteins, including two taste modifying proteins. Sweet proteins stand out among sweet molecules because their volume is not compatible with an interaction with orthosteric active sites of the sweet taste receptor. The best explanation of their mechanism of action is the interaction with the external surface of the sweet taste receptor, according to a model that has been named "wedge model". It is hypothesized that this mode of action may be related to the ability of other members of their protein families to inhibit different enzymes.
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Affiliation(s)
- Delia Picone
- Università di Napoli Federico II, via Cinthia 45, Naples 80126, Italy
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