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1.
Mol Plant ; 15(5): 802-804, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35158096
2.
Biomed Res Int ; 2021: 4604856, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527737

RESUMO

IFN-γ licensing to mesenchymal stem cells (MSCs) is applied to enhance the therapeutic potential of MSCs. However, although the features of MSCs are affected by several stimuli, little information is available on changes to the therapeutic potential of IFN-γ-licensed differentiated MSCs during xenogeneic applications. Therefore, the present study is aimed at clarifying the effects of adipogenic/osteogenic differentiation and IFN-γ licensing on the in vitro immunomodulatory and migratory properties of porcine bone marrow-derived MSCs in xenogeneic applications using human peripheral blood mononuclear cells (PBMCs). IFN-γ licensing in differentiated MSCs lowered lineage-specific gene expression but did not affect MSC-specific cell surface molecules. Although indoleamine 2,3 deoxygenase (IDO) activity and expression were increased after IFN-γ licensing in undifferentiated MSCs, they were reduced after differentiation. IFN-γ licensing to differentiated MSCs elevated the reduced IDO expression in differentiated MSCs; however, the increase was not sufficient to reach to the level achieved by undifferentiated MSCs. During a mixed lymphocyte reaction with quantification of TNF-α concentration, proliferation and activation of xenogeneic PBMCs were suppressed by undifferentiated MSCs but inhibited to a lesser extent by differentiated MSCs. IFN-γ licensing increasingly suppressed proliferation of PBMCs in undifferentiated MSCs but it was incapable of elevating the reduced immunosuppressive ability of differentiated MSCs. Migratory ability through a scratch assay and gene expression study was reduced in differentiated MSCs than their undifferentiated counterparts; IFN-γ licensing was unable to enhance the reduced migratory ability in differentiated MSCs. Similar results were found in a Transwell system with differentiated MSCs in the upper chamber toward xenogeneic PBMCs in the lower chamber, despite IFN-γ licensing increased the migratory ability of undifferentiated MSCs. Overall, IFN-γ licensing did not enhance the reduced immunomodulatory and migratory properties of differentiated MSCs in a xenogeneic application. This study provides a better understanding of the ways in which MSC therapy can be applied.


Assuntos
Interferon gama/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Animais , Medula Óssea/metabolismo , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Xenoenxertos/metabolismo , Humanos , Imunomodulação/efeitos dos fármacos , Interferon gama/fisiologia , Células-Tronco Mesenquimais/fisiologia , Osteogênese/efeitos dos fármacos , Suínos , Fator de Necrose Tumoral alfa/metabolismo
3.
Biomed Res Int ; 2021: 5540877, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337022

RESUMO

Mesenchymal stem cells (MSCs) are valuable candidates in tissue engineering and stem cell-based therapy. Traditionally, MSCs derived from various tissues have been successfully expanded in vitro using adherent culture plates commonly called as monolayer two-dimensional (2D) cultures. Recently, many studies demonstrated that stemness and multilineage differentiation potential could be enhanced to greater extent when MSCs are cultured as suspended aggregates by means of three-dimensional (3D) culturing techniques. However, there are limited reports on changed mitochondrial metabolism on 3D spheroid formation of MSCs. Therefore, the present study was aimed at investigating the stemness, differentiation potential, and mitochondrial metabolism capacity of 3D dental pulp-derived MSC (DPSC) spheroids in comparison to monolayer cultured DPSCs. We isolated dental pulp-derived MSCs (DPSCs) and successfully developed a 3D culture system which facilitated the formation of MSC spheroids. The cell aggregation was observed after 2 hours, and spheroids were formed after 24 hours and remained in shape for 72 hours. After spheroid formation, the levels of pluripotent markers increased along with enhancement in adipogenic and osteogenic potential compared to 2D cultured control cells. However, decreased proliferative capacity, cell cycle arrest, and elevated apoptosis rate were observed with the time course of the 3D culture except for the initial 24-hour aggregation. Furthermore, oxygen consumption rates of living cells decreased with the time course of the aggregation except for the initial 24 hours. Overall, our study indicated that the short-term 3D culture of MSCs could be a suitable alternative to culture the cells.


Assuntos
Diferenciação Celular , Polpa Dentária/citologia , Células-Tronco Mesenquimais/citologia , Mitocôndrias/metabolismo , Células-Tronco Pluripotentes/citologia , Esferoides Celulares/citologia , Adipogenia , Apoptose , Biomarcadores/metabolismo , Técnicas de Cultura de Células , Ciclo Celular , Proliferação de Células , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Consumo de Oxigênio , Células-Tronco Pluripotentes/metabolismo , Esferoides Celulares/metabolismo
4.
Mol Plant Pathol ; 22(6): 694-709, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33825303

RESUMO

The plant hypersensitive response (HR), a rapid cell death at the point of pathogenesis, is mediated by nucleotide-binding site, leucine-rich repeat (NLR) resistance proteins (R-proteins) that recognize the presence of specific pathogen-derived proteins. Rp1-D21 is an autoactive maize NLR R-protein that triggers HR spontaneously. We previously mapped loci associated with variation in the strength of HR induced by Rp1-D21. Here we identify the E3 ligase ZmMIEL1 as the causal gene at a chromosome 10 modifier locus. Transient ZmMIEL1 expression in Nicotiana benthamiana reduced HR induced by Rp1-D21, while suppression of ZmMIEL1 expression in maize carrying Rp1-D21 increased HR. ZmMIEL1 also suppressed HR induced by another autoactive NLR, the Arabidopsis R-protein RPM1D505V, in N. benthamiana. We demonstrated that ZmMIEL1 is a functional E3 ligase and that the effect of ZmMIEL1 was dependent on the proteasome but also that levels of Rp1-D21 and RPM1D505V were not reduced when coexpressed with ZmMIEL1 in the N. benthamiana system. By comparison to a similar system in Arabidopsis, we identify ZmMYB83 as a potential target of ZmMIEL1. Suppression of ZmMYB83 expression in maize lines carrying Rp1-D21 suppressed HR. Suppression of ZmMIEL1 expression caused an increase in ZmMYB83 transcript and protein levels in N. benthamiana and maize. Using coimmunoprecipitation and bimolecular fluorescence complementation assays, we demonstrated that ZmMIEL1 and ZmMYB83 physically interacted. Additionally, ZmMYB83 and ZmMIEL1 regulated the expression of a set of maize very long chain fatty acid (VLCFA) biosynthetic genes that may be involved in regulating HR.


Assuntos
Resistência à Doença , Doenças das Plantas/imunologia , Complexo de Endopeptidases do Proteassoma , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Zea mays/genética , Morte Celular , Genes Reporter , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Filogenia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tabaco/genética , Tabaco/fisiologia , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética , Zea mays/enzimologia , Zea mays/imunologia , Zea mays/fisiologia
5.
Biomedicines ; 9(2)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670230

RESUMO

One of the most severe and devastating cancer is pancreatic cancer. Pancreatic ductal adenocarcinoma (PDAC) is one of the major pancreatic exocrine cancer with a poor prognosis and growing prevalence. It is the most deadly disease, with an overall five-year survival rate of 6% to 10%. According to various reports, it has been demonstrated that pancreatic cancer stem cells (PCSCs) are the main factor responsible for the tumor development, proliferation, resistance to anti-cancer drugs, and recurrence of tumors after surgery. PCSCs have encouraged new therapeutic methods to be explored that can specifically target cancer cells. Furthermore, stem cells, especially mesenchymal stem cells (MSCs), are known as influential anti-cancer agents as they function through anti-inflammatory, paracrine, cytokines, and chemokine's action. The properties of MSCs, such as migration to the site of infection and host immune cell activation by its secretome, seem to control the microenvironment of the pancreatic tumor. MSCs secretome exhibits similar therapeutic advantages as a conventional cell-based therapy. Moreover, the potential for drug delivery could be enhanced by engineered MSCs to increase drug bioactivity and absorption at the tumor site. In this review, we have discussed available therapeutic strategies, treatment hurdles, and the role of different factors such as PCSCs, cysteine, GPCR, PKM2, signaling pathways, immunotherapy, and NK-based therapy in pancreatic cancer.

6.
Int J Med Sci ; 18(5): 1259-1268, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33526987

RESUMO

Background: Multipotent and immune privileged properties of mesenchymal stem cells (MSCs) were investigated for the treatment of various clinical diseases. For the years, many researches into the animal studies evaluated human stem cell therapeutic capacity related to the regenerative medicine. However, there were limited reports on immune privileged properties of human MSCs in animal studies. The present study investigated hematological and biochemical parameter and lymphocyte subset in mini-pigs following human MSCs transplantation as a means of validation of reliability that influence the animal test results. Methods: The miniature pigs were transplanted with human MSCs seeded with scaffold. After transplantation, all animals were evaluated by CBC, biochemistry and lymphocyte subset test. After 9 weeks, all pigs were sacrificed and organs were histologically analyzed. Results: CBC test showed that levels of RBC were decreased and reticulocyte, WBC and neutrophil were increased in transient state initially after transplantation, but returned to normal value. The proportion of B lymphocyte and cytotoxic T cell were also initially enhanced within the normal range temporarily. The female and male miniature pigs showed normal ranges for blood chemistry assessments. During the 9 weeks post-operative period, the animals showed a continuous increase in body weight and length. Furthermore, no abnormal findings were observed from the histological analysis of sacrificed pigs. Conclusions: Overall, miniature pigs transplanted with human MSCs seeded with scaffold were found to have physiologically similar results to normal animals. This result might be a reliable indicator of the animal experiments using miniature pigs with human MSCs.


Assuntos
Privilégio Imunológico , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/imunologia , Porco Miniatura/imunologia , Animais , Contagem de Células Sanguíneas , Feminino , Humanos , Masculino , Modelos Animais , Medicina Regenerativa/métodos , Reprodutibilidade dos Testes , Suínos , Tecidos Suporte , Transplante Heterólogo
7.
Mol Plant Pathol ; 22(4): 465-479, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33641256

RESUMO

Common rust, caused by Puccinia sorghi, is a widespread and destructive disease of maize. The Rp1-D gene confers resistance to the P. sorghi IN2 isolate, mediating a hypersensitive cell death response (HR). To identify differentially expressed genes (DEGs) and metabolites associated with the compatible (susceptible) interaction and with Rp1-D-mediated resistance in maize, we performed transcriptomics and targeted metabolome analyses of P. sorghi IN2-infected leaves from the near-isogenic lines H95 and H95:Rp1-D, which differed for the presence of Rp1-D. We observed up-regulation of genes involved in the defence response and secondary metabolism, including the phenylpropanoid, flavonoid, and terpenoid pathways. Metabolome analyses confirmed that intermediates from several transcriptionally up-regulated pathways accumulated during the defence response. We identified a common response in H95:Rp1-D and H95 with an additional H95:Rp1-D-specific resistance response observed at early time points at both transcriptional and metabolic levels. To better understand the mechanisms underlying Rp1-D-mediated resistance, we inferred gene regulatory networks occurring in response to P. sorghi infection. A number of transcription factors including WRKY53, BHLH124, NKD1, BZIP84, and MYB100 were identified as potentially important signalling hubs in the resistance-specific response. Overall, this study provides a novel and multifaceted understanding of the maize susceptible and resistance-specific responses to P. sorghi.


Assuntos
Interações Hospedeiro-Patógeno , Metaboloma , Doenças das Plantas/microbiologia , Puccinia/fisiologia , Transcriptoma , Zea mays/genética , Perfilação da Expressão Gênica , Metabolômica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Zea mays/microbiologia
8.
Biomed Res Int ; 2021: 8858412, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33553433

RESUMO

Previous studies have shown that mesenchymal stem cells (MSCs) derived from various tissue sources can be differentiated into smooth muscle-like cells (SMLCs) in vitro. In this paper, dental pulp-derived mesenchymal stem cells (DPSCs) were evaluated for their differentiation ability towards smooth muscle-like cells (SMLCs) under the effect of widely used cytokines (TGF-ß1 and PDGF-BB) with special focus on different culturing environments. For this purpose, both the commercially used culturing plates (Norm-c) and 0.1% gelatin-precoated (Gel-c) plates were used. Isolated cells displayed plastic adherence, pluripotency and cell surface marker profiling, and adipogenic and osteogenic differentiation potential with lineage specific marker expression. Differentiated cells induced under different culturing plates showed successful differentiation into SMLCs by positively expressing smooth muscle cell (SMC) specific markers both at the mRNA and protein levels. Gelatin coating could substantially enhance DPSC differentiation potential than Norm-c-induced cells. However, the absence of mature marker MHY-11 by immunostaining results from all treatment groups further indicated the development of immature and synthetic SMLCs. Finally, it was concluded that DPSC differentiation ability into SMLCs can be enhanced under cytokine treatment as well as by altering the cellular niche by precoating the culturing plates with suitable substrates. However, to get fully functional, contractile, and mature SMLCs, still many different cytokine cocktail combinations and more suitable coating substrates will be needed.


Assuntos
Técnicas de Cultura de Células/instrumentação , Diferenciação Celular/efeitos dos fármacos , Polpa Dentária/citologia , Células-Tronco Mesenquimais/citologia , Miócitos de Músculo Liso/citologia , Becaplermina/farmacologia , Biomarcadores/metabolismo , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Linhagem da Célula , Células Cultivadas , Colágeno , Meios de Cultura/química , Meios de Cultura/farmacologia , Géis , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Células-Tronco Pluripotentes/fisiologia , Fator de Crescimento Transformador beta1/farmacologia
9.
Mol Plant Microbe Interact ; 34(6): 606-616, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33507801

RESUMO

The maize gene Rp1-D21 is a mutant form of the gene Rp1-D that confers resistance to common rust. Rp1-D21 triggers a spontaneous defense response that occurs in the absence of the pathogen and includes a programed cell death called the hypersensitive response (HR). Eleven plants heterozygous for Rp1-D21, in four different genetic backgrounds, were identified that had chimeric leaves with lesioned sectors showing HR abutting green nonlesioned sectors lacking HR. The Rp1-D21 sequence derived from each of the lesioned portions of leaves was unaltered from the expected sequence whereas the Rp1-D21 sequences from nine of the nonlesioned sectors displayed various mutations, and we were unable to amplify Rp1-D21 from the other two nonlesioned sectors. In every case, the borders between the sectors were sharp, with no transition zone, suggesting that HR and chlorosis associated with Rp1-D21 activity was cell autonomous. Expression of defense response marker genes was assessed in the lesioned and nonlesioned sectors as well as in near-isogenic plants lacking and carrying Rp1-D21. Defense gene expression was somewhat elevated in nonlesioned sectors abutting sectors carrying Rp1-D21 compared with near-isogenic plants lacking Rp1-D21. This suggests that, whereas the HR itself was cell autonomous, other aspects of the defense response initiated by Rp1-D21 were not.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Basidiomycota , Zea mays , Resistência à Doença/genética , Doenças das Plantas/genética , Folhas de Planta , Proteínas de Plantas/genética , Zea mays/genética
10.
New Phytol ; 229(1): 532-547, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32810286

RESUMO

Plants possess hundreds of intracellular immune receptors encoding nucleotide-binding domain leucine-rich repeat (NLR) proteins. Full-length NLRs or a specific domain of NLRs often induce plant cell death in the absence of pathogen infection. In this study we used genome-wide transient expression analysis to identify a group of NLRs (ANLs; ancient and autonomous NLRs) carrying autoactive coiled-coil (CCA ) domains in pepper (Capsicum annuum). CCA -mediated cell death mimics hypersensitive cell death triggered by the interaction between NLRs and pathogen effectors. Sequence alignment and mutagenesis analyses revealed that the intact α1 helix of CCA s is critical for both CCA - and ANL-mediated cell death. Cell death induced by CCA s does not require NRG1/ADR1 or NRC type helper NLRs, suggesting ANLs may function as singleton NLRs. We also found that CCA s localize to the plasma membrane, as demonstrated for Arabidopsis singleton NLR ZAR1. Extended studies revealed that autoactive CCA s are well conserved in other Solanaceae plants as well as in rice, a monocot plant. Further phylogenetic analyses revealed that ANLs are present in all tested seed plants (spermatophytes). Our study not only uncovers the autonomous NLR clade in plants but also provides powerful resources for dissecting the underlying molecular mechanism of NLR-mediated cell death in plants.


Assuntos
Capsicum , Imunidade Vegetal , Capsicum/genética , Proteínas NLR/genética , Filogenia , Doenças das Plantas/genética , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Sementes/genética
11.
Mol Plant Pathol ; 21(12): 1662-1676, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33037769

RESUMO

Plant disease resistance proteins (R-proteins) detect specific pathogen-derived molecules, triggering a defence response often including a rapid localized cell death at the point of pathogen penetration called the hypersensitive response (HR). The maize Rp1-D21 gene encodes a protein that triggers a spontaneous HR causing spots on leaves in the absence of any pathogen. Previously, we used fine mapping and functional analysis in a Nicotiana benthamiana transient expression system to identify and characterize a number of genes associated with variation in Rp1-D21-induced HR. Here we describe a system for characterizing genes mediating HR, using virus-induced gene silencing (VIGS) in a maize line carrying Rp1-D21. We assess the roles of 12 candidate genes. Three of these genes, SGT1, RAR1, and HSP90, are required for HR induced by a number of R-proteins across several plant-pathogen systems. We confirmed that maize HSP90 was required for full Rp1-D21-induced HR. However, suppression of SGT1 expression unexpectedly increased the severity of Rp1-D21-induced HR while suppression of RAR1 expression had no measurable effect. We confirmed the effects on HR of two genes we had previously validated in the N. benthamiana system, hydroxycinnamoyltransferase and caffeoyl CoA O-methyltransferase. We further showed the suppression the expression of two previously uncharacterized, candidate genes, IQ calmodulin binding protein (IQM3) and vacuolar protein sorting protein 37, suppressed Rp1-D21-induced HR. This approach is an efficient way to characterize the roles of genes modulating the hypersensitive defence response and other dominant lesion phenotypes in maize.


Assuntos
Inativação Gênica , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Tabaco/genética , Zea mays/genética , Aciltransferases/genética , Aciltransferases/metabolismo , Morte Celular , Resistência à Doença , Metiltransferases/genética , Metiltransferases/metabolismo , Fenótipo , Doenças das Plantas/virologia , Imunidade Vegetal , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/virologia , Proteínas de Plantas/genética , Ligação Proteica , Tabaco/imunologia , Tabaco/virologia , Zea mays/imunologia , Zea mays/virologia
12.
Plant J ; 104(3): 581-595, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32748440

RESUMO

Similar progressive leaf lesion phenotypes, named conring for "concentric ring," were identified in 10 independently derived maize lines. Complementation and mapping experiments indicated that the phenotype had the same genetic basis in each line - a single recessive gene located in a 1.1-Mb region on chromosome 2. Among the 15 predicted genes in this interval, Zm00001d003866 (subsequently renamed Conring or Cnr) had insertions of four related 138 bp transposable element (TE) sequences at precisely the same site in exon 4 in nine of the 10 cnr alleles. The 10th cnr allele had a distinct insertion of 226 bp of in exon 3. Genetic evidence suggested that the 10 cnr alleles were independently derived, and arose during the derivation of each line. The four TEs, named COINa (for COnring INsertion) through COINd, have not been previously characterized and consist entirely of imperfect 69-bp terminal inverted repeats characteristic of the Foldback class of TEs. They belong to three clades of a family of maize TEs comprising hundreds of sequences in the genome of the B73 maize line. COIN elements preferentially insert at TNA sequences with a preference for C and G nucleotides in the immediately flanking 5' and 3' regions, respectively. They produce a three-base target site duplication and do not have homology to other characterized TEs. We propose that Cnr is an unstable gene that is mutated insertionally at high frequency, most commonly due to COIN element insertions at a specific site in the gene.


Assuntos
Elementos de DNA Transponíveis/genética , Zea mays/genética , Morte Celular/genética , Genoma de Planta/genética , Sequências Repetidas Terminais/genética
13.
Planta ; 249(5): 1477-1485, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30694389

RESUMO

MAIN CONCLUSION: The gene GRMZM2G318346 which encodes a cytochrome b-c1 complex subunit 7 is associated with variation in strength of the hypersensitive response in maize. We previously identified a QTL at 3,545,354 bp (B73 reference genome V2) on maize chromosome 5 associated with variation in the hypersensitive response (HR) conferred by the autoactive R-gene Rp1-D21 (Olukolu et al. in PLoS Genet 10:e1004562 2014). In this study, we show that a gene at this locus, GRMZM2G318346 which encodes a cytochrome b-c1 complex subunit seven (ZmQCR7), an important part of the mitochondrial electron transport chain, can suppress HR mediated by Rp1-D21 in a transient expression assay. ZmQCR7 alleles from two maize lines, W22 and B73 differ for the encoded proteins at just two sites, amino acid 27 (threonine and alanine in B73 and W22, respectively) and amino acid 109 (asparagine and serine), however, the B73 allele is much more effective at suppressing HR. We show that variation at amino acid 27 controlled this variation in HR-suppressing effects. We furthermore demonstrate that the B73 allele of ZmQCR7 can suppress HR induced by RPM1(D505 V), another autoactive R-gene, and that Arabidopsis homologs of ZmQCR7 can also suppress NLR-induced HR. The implications of these findings are discussed.


Assuntos
Citocromos b/metabolismo , Citocromos c1/metabolismo , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Zea mays/metabolismo , Citocromos b/genética , Citocromos c1/genética , Resistência à Doença/genética , Resistência à Doença/fisiologia , Proteínas de Plantas/genética , Locos de Características Quantitativas/genética , Espécies Reativas de Oxigênio/metabolismo , Zea mays/genética
14.
Sci Data ; 5: 180103, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29870035

RESUMO

Hot pepper (Capsicum annuum) is one of the most consumed vegetable crops in the world and useful to human as it has many nutritional and medicinal values. Genomic resources of pepper are publically available since the pepper genomes have been completed and massive data such as transcriptomes have been deposited. Nevertheless, global transcriptome profiling is needed to identify molecular mechanisms related to agronomic traits in pepper, but limited analyses are published. Here, we report the comprehensive analysis of pepper transcriptomes during fruit ripening and pathogen infection. For the ripening, transcriptome data were obtained from placenta and pericarp at seven developmental stages. To reveal global transcriptomic landscapes during infection, leaves at six time points post-infection by one of three pathogens (Phytophthora infestans, Pepper mottle virus, and Tobacco mosaic virus P0 strain) were profiled. The massive parallel transcriptome profiling in this study will serve as a valuable resource for detection of molecular networks of fruit development and disease resistance in Capsicum annuum.


Assuntos
Capsicum/genética , Perfilação da Expressão Gênica , Doenças das Plantas/genética , Transcriptoma , Capsicum/parasitologia , Capsicum/virologia , Phytophthora infestans , Doenças das Plantas/parasitologia , Doenças das Plantas/virologia , Potyvirus , Vírus do Mosaico do Tabaco
15.
Mol Plant Microbe Interact ; 31(9): 906-913, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29663867

RESUMO

The pepper Pvr4 protein encoding coiled-coil (CC) nucleotide-binding (NB) leucine-rich repeat (LRR) (NLR) confer hypersensitive response (HR) to potyviruses, including Pepper mottle virus (PepMoV), by recognizing the viral avirulence protein NIb. To figure out the Pvr4-mediated HR mechanism, we analyzed signaling component genes and structure-function relationships of Pvr4, using chimeras and deletion mutants in Nicotiana benthamiana. Molecular chaperone components including HSP90, SGT1, and RAR1 were required, while plant hormones and mitogen-activated protein kinase signaling components had little effect on Pvr4-NIb-mediated HR cell death. Domain swap analyses indicated that the LRR domain of Pvr4 determines recognition of PepMoV-NIb. Our deletion analysis further revealed that the CC domain or CC-NBARC domain alone can trigger autoactive cell death in N. benthamiana. However, the fragments having only an LRR domain could suppress CC-NBARC domain-induced cell death in trans. Further, C-terminal truncation analysis of Pvr4 revealed that a minimum three of five LRR exons showing high similarity was essential for Pvr4 function. The LRR domain may maintain Pvr4 in an inactive state in the absence of NIb. These results provide further insight into the structure and function of NLR protein signaling in plants.


Assuntos
Capsicum/genética , Resistência à Doença/genética , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Potyvirus/fisiologia , Transdução de Sinais , Morte Celular , Doenças das Plantas/virologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/virologia , Proteínas de Plantas/genética , Domínios Proteicos , Proteínas/genética , Proteínas/metabolismo , Tabaco/genética , Tabaco/fisiologia , Tabaco/virologia
16.
Genome Biol ; 18(1): 210, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29089032

RESUMO

BACKGROUND: Transposable elements are major evolutionary forces which can cause new genome structure and species diversification. The role of transposable elements in the expansion of nucleotide-binding and leucine-rich-repeat proteins (NLRs), the major disease-resistance gene families, has been unexplored in plants. RESULTS: We report two high-quality de novo genomes (Capsicum baccatum and C. chinense) and an improved reference genome (C. annuum) for peppers. Dynamic genome rearrangements involving translocations among chromosomes 3, 5, and 9 were detected in comparison between C. baccatum and the two other peppers. The amplification of athila LTR-retrotransposons, members of the gypsy superfamily, led to genome expansion in C. baccatum. In-depth genome-wide comparison of genes and repeats unveiled that the copy numbers of NLRs were greatly increased by LTR-retrotransposon-mediated retroduplication. Moreover, retroduplicated NLRs are abundant across the angiosperms and, in most cases, are lineage-specific. CONCLUSIONS: Our study reveals that retroduplication has played key roles for the massive emergence of NLR genes including functional disease-resistance genes in pepper plants.


Assuntos
Capsicum/genética , Resistência à Doença/genética , Evolução Molecular , Duplicação Gênica , Genes de Plantas , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Retroelementos/genética , Cromossomos de Plantas/genética , Especiação Genética , Anotação de Sequência Molecular , Família Multigênica , Proteínas NLR/genética , Fases de Leitura Aberta/genética , Filogenia , Padrões de Referência , Análise de Sequência de RNA , Especificidade da Espécie , Sequências Repetidas Terminais/genética
17.
New Phytol ; 213(2): 886-899, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27612097

RESUMO

Plants have evolved hundreds of nucleotide-binding and leucine-rich domain proteins (NLRs) as potential intracellular immune receptors, but the evolutionary mechanism leading to the ability to recognize specific pathogen effectors is elusive. Here, we cloned Pvr4 (a Potyvirus resistance gene in Capsicum annuum) and Tsw (a Tomato spotted wilt virus resistance gene in Capsicum chinense) via a genome-based approach using independent segregating populations. The genes both encode typical NLRs and are located at the same locus on pepper chromosome 10. Despite the fact that these two genes recognize completely different viral effectors, the genomic structures and coding sequences of the two genes are strikingly similar. Phylogenetic studies revealed that these two immune receptors diverged from a progenitor gene of a common ancestor. Our results suggest that sequence variations caused by gene duplication and neofunctionalization may underlie the evolution of the ability to specifically recognize different effectors. These findings thereby provide insight into the divergent evolution of plant immune receptors.


Assuntos
Capsicum/genética , Capsicum/virologia , Resistência à Doença/genética , Evolução Molecular , Genes de Plantas , Doenças das Plantas/virologia , Potyvirus/fisiologia , Segregação de Cromossomos/genética , Loci Gênicos , Família Multigênica , Mapeamento Físico do Cromossomo , Plantas Geneticamente Modificadas , Tabaco/virologia
18.
Mol Plant Microbe Interact ; 30(1): 5-15, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27925500

RESUMO

Nonhost resistance, a resistance of plant species against all nonadapted pathogens, is considered the most durable and efficient immune system of plants but yet remains elusive. The underlying mechanism of nonhost resistance has been investigated at multiple levels of plant defense for several decades. In this review, we have comprehensively surveyed the latest literature on nonhost resistance in terms of preinvasion, metabolic defense, pattern-triggered immunity, effector-triggered immunity, defense signaling, and possible application in crop protection. Overall, we summarize the current understanding of nonhost resistance mechanisms. Pre- and postinvasion is not much deviated from the knowledge on host resistance, except for a few specific cases. Further insights on the roles of the pattern recognition receptor gene family, multiple interactions between effectors from nonadapted pathogen and plant factors, and plant secondary metabolites in host range determination could expand our knowledge on nonhost resistance and provide efficient tools for future crop protection using combinational biotechnology approaches. [Formula: see text] Copyright © 2017 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .


Assuntos
Resistência à Doença , Interações Hospedeiro-Patógeno , Plantas/imunologia , Produtos Agrícolas/crescimento & desenvolvimento , Imunidade Vegetal , Transdução de Sinais
19.
PLoS One ; 10(3): e0119639, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25760376

RESUMO

Potyviruses are one of the most destructive viral pathogens of Solanaceae plants. In Capsicum annuum landrace CM334, a broad-spectrum gene, Pvr4 is known to be involved in resistance against multiple potyviruses, including Pepper mottle virus (PepMoV), Pepper severe mosaic virus (PepSMV), and Potato virus Y (PVY). However, a potyvirus avirulence factor against Pvr4 has not been identified. To identify the avirulence factor corresponding to Pvr4 in potyviruses, we performed Agrobacterium-mediated transient expressions of potyvirus protein coding regions in potyvirus-resistant (Pvr4) and -susceptible (pvr4) pepper plants. Hypersensitive response (HR) was observed only when a RNA-dependent RNA polymerase (NIb) of PepMoV, PepSMV, or PVY was expressed in Pvr4-bearing pepper leaves in a genotype-specific manner. In contrast, HR was not observed when the NIb of Tobacco etch virus (TEV), a virulent potyvirus, was expressed in Pvr4-bearing pepper leaves. Our results clearly demonstrate that NIbs of PepMoV, PepSMV, and PVY serve as avirulence factors for Pvr4 in pepper plants.


Assuntos
Capsicum/microbiologia , Proteínas de Plantas/metabolismo , Potyvirus/enzimologia , RNA Polimerase Dependente de RNA/metabolismo , Agrobacterium/genética , Agrobacterium/metabolismo , Capsicum/genética , Capsicum/metabolismo , Resistência à Doença , Genótipo , Folhas de Planta/microbiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/microbiologia , RNA Polimerase Dependente de RNA/genética , Proteínas Virais/metabolismo , Virulência
20.
New Phytol ; 203(3): 926-38, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24889686

RESUMO

Nonhost resistance (NHR) is a plant immune response to resist most pathogens. The molecular basis of NHR is poorly understood, but recognition of pathogen effectors by immune receptors, a response known as effector-triggered immunity, has been proposed as a component of NHR. We performed transient expression of 54 Phytophthora infestansRXLR effectors in pepper (Capsicum annuum) accessions. We used optimized heterologous expression methods and analyzed the inheritance of effector-induced cell death in an F2 population derived from a cross between two pepper accessions. Pepper showed a localized cell death response upon inoculation with P. infestans, suggesting that recognition of effectors may contribute to NHR in this system. Pepper accessions recognized as many as 36 effectors. Among the effectors, PexRD8 and Avrblb2 induced cell death in a broad range of pepper accessions. Segregation of effector-induced cell death in an F2 population derived from a cross between two pepper accessions fit 15:1, 9:7 or 3:1 ratios, depending on the effector. Our genetic data suggest that a single or two independent/complementary dominant genes are involved in the recognition of RXLR effectors. Multiple loci recognizing a series of effectors may underpin NHR of pepper to P. infestans and confer resistance durability.


Assuntos
Capsicum/imunologia , Resistência à Doença/imunologia , Interações Hospedeiro-Patógeno/imunologia , Phytophthora infestans/fisiologia , Doenças das Plantas/imunologia , Proteínas/metabolismo , Receptores de Reconhecimento de Padrão/metabolismo , Motivos de Aminoácidos , Capsicum/genética , Capsicum/microbiologia , Morte Celular , Cruzamentos Genéticos , Ecótipo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Loci Gênicos , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/microbiologia , Potexvirus/fisiologia , Reprodutibilidade dos Testes , Vírion/fisiologia
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