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1.
Physiol Plant ; 176(3): e14374, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38837422

RESUMO

Heat stress substantially reduces tomato (Solanum lycopersicum) growth and yield globally, thereby jeopardizing food security. DnaJ proteins, constituents of the heat shock protein system, protect cells from diverse environmental stresses as HSP-70 molecular co-chaperones. In this study, we demonstrated that AdDjSKI, a serine-rich DnaJ III protein induced by pathogens, plays an important role in stabilizing photosystem II (PSII) in response to heat stress. Our results revealed that transplastomic tomato plants expressing the AdDjSKI gene exhibited increased levels of total soluble proteins, improved growth and chlorophyll content, reduced malondialdehyde (MDA) accumulation, and diminished PSII photoinhibition under elevated temperatures when compared with wild-type (WT) plants. Intriguingly, these transplastomic plants maintained higher levels of D1 protein under elevated temperatures compared with the WT plants, suggesting that overexpression of AdDjSKI in plastids is crucial for PSII protection, likely due to its chaperone activity. Furthermore, the transplastomic plants displayed lower accumulation of superoxide radical (O2 •─) and H2O2, in comparison with the WT plants, plausibly attributed to higher superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities. This also coincides with an enhanced expression of corresponding genes, including SlCuZnSOD, SlFeSOD, SlAPX2, and SltAPX, under heat stress. Taken together, our findings reveal that chloroplastic expression of AdDjSKI in tomatoes plays a critical role in fruit yield, primarily through a combination of delayed senescence and stabilizing PSII under heat stress.


Assuntos
Frutas , Resposta ao Choque Térmico , Complexo de Proteína do Fotossistema II , Folhas de Planta , Proteínas de Plantas , Plastídeos , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Complexo de Proteína do Fotossistema II/genética , Resposta ao Choque Térmico/genética , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/fisiologia , Frutas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo , Plastídeos/metabolismo , Plastídeos/genética , Clorofila/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Proteínas de Choque Térmico HSP40/genética , Plantas Geneticamente Modificadas , Senescência Vegetal/genética , Regulação da Expressão Gênica de Plantas , Malondialdeído/metabolismo
2.
Planta ; 256(6): 103, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307739

RESUMO

MAIN CONCLUSION: Manipulation of autophagic pathway represents a tremendous opportunity for designing climate-smart crops with improved yield and better adaptability to changing environment. For exploiting autophagy to its full potential, identification and comprehensive characterization of adapters/receptor complex and elucidation of its regulatory network in crop plants is highly warranted.  Autophagy is a major intracellular trafficking pathway in eukaryotes involved in vacuolar degradation of cytoplasmic constituents, mis-folded proteins, and defective organelles. Under optimum conditions, autophagy operates at a basal level to maintain cellular homeostasis, but under stressed conditions, it is induced further to provide temporal stress relief. Our understanding of this highly dynamic process has evolved exponentially in the past few years with special reference to several plant-specific roles of autophagy. Here, we review the most recent advances in the field of autophagy in plants and discuss its potential implications in designing crops with improved stress and disease-tolerance, enhanced yield potential, and improved capabilities for producing metabolites of high economic value. We also assess the current knowledge gaps and the possible strategies to develop a robust module for biotechnological application of autophagy to enhance bioeconomy and sustainability of agriculture.


Assuntos
Autofagia , Desenvolvimento Vegetal , Vacúolos , Produtos Agrícolas/genética
3.
Physiol Mol Biol Plants ; 25(4): 1073-1082, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31402825

RESUMO

Manifestation of male sterility in plants is an important requirement for hybrid seed production. Tapetum cell layer of anther is a primary target for genetic manipulation for male sterility. In our previous report, the targeted expression of Arachis cysteine protease in tapetum led to premature degeneration of tapetal layer that resulted in complete male sterility in transgenic tobacco plants. To correlate cysteine protease mediated cell death of tapetum, transmission electron microscopy (TEM) and proteomic pattern of anthers of cysteine protease induced male sterile plant were compared with the untransformed control plant. TEM study revealed the abnormal growth of tapetal cells exhibiting excessive vacuolization that synchronized with irregular exine wall formation of the microspores. In anther proteome, a total 250 protein spots were detected that were reproducible and exhibited similar distribution pattern. Further, anther proteome of male sterile plant showed the significant upregulation (≥ 1.5) of 56 protein spots. Using Mass spectroscopy (MALDI TOF/TOF), we have identified 14 protein spots that were involved in several processes such as energy metabolism, protein synthesis, plastid protein, lipid metabolism, and cell wall assembly. Upregulation of patatin-like protein-2 homolog, carboxylesterase 17 and dicer like protein-4 in male sterile anthers that have been demonstrated to induce cell death, suggesting that cysteine protease mediated premature tapetal cell death might involve the lipid peroxidation pathway in coordination with gene silencing mechanism.

4.
Proteomics ; 18(16): e1700418, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29920934

RESUMO

Powdery mildew (PM, caused by Golovinomyces orontii) is one of the major diseases on sunflower that causes severe yield losses in the tropics. Sources of resistance to PM are reported in an exotic accession and some wild Helianthus species. The present study aims at quantitative proteomic analysis of susceptible, resistant, and immune genotypes of sunflower in response to PM infection at 3, 7, 10 days post infection. The majority of differentially expressed proteins in the resistant genotype belonged to oxidative stress (catalase, ATP-sulfurylase, and formate dehydrogenase), defense (HSP-70, heat shock transcription factors), and photosynthesis (LHCB3). In case of immune genotype, 50% of proteins are related to photosynthesis, which play a key role in plant immunity, whereas a few similar proteins are also expressed in the susceptible genotype, but in their reduced abundance besides being inadequate in timing of expression probably leading to its susceptibility to PM. KEGG enrichment analysis shows that carbon metabolism (6-phosphogluconate dehydrogenase, pyruvate dehydrogenase, glutamine synthetase), photosynthesis, and plant-pathogen protein pathways are key pathways governing the resistance. The transcriptional expression of eight of nine differentially expressed proteins are in agreement with the expression of proteins at the corresponding time. The present study provides information on the key proteins that are upregulated in resistant and immune genotypes which restrict the disease progression and constitutes the first quantitative proteomic data of sunflower-PM infection process.


Assuntos
Ascomicetos/fisiologia , Helianthus/genética , Helianthus/imunologia , Doenças das Plantas/genética , Proteômica/métodos , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Genótipo , Helianthus/microbiologia , Fotossíntese , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Plant Biotechnol J ; 13(1): 73-84, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25236372

RESUMO

We have identified a transcript derived fragment (TDF) corresponding to SGT1 in a study of differential gene expression on the resistant wild peanut, Arachis diogoi, upon challenge from the late leaf spot pathogen, Phaeoisariopsis personata, and cloned its full-length cDNA followed by subsequent validation through q-PCR. Sodium nitroprusside, salicylic acid, ethephon and methyl jasmonate induced the expression of AdSGT1, while the treatment with abscisic acid did not elicit its up-regulation. AdSGT1 is localized to both nucleus and cytoplasm. Its overexpression induced hypersensitive-like cell death in tobacco under transient conditional expression using the estradiol system, and this conditional expression of AdSGT1 was also associated with the up-regulation of NtHSR203J, HMGR and HIN1, which have been shown to be associated with hypersensitive response in tobacco in earlier studies. Expression of the cDNA in a susceptible cultivated peanut variety enhanced its resistance against the late leaf spot pathogen, Phaeoisariopsis personata, while the heterologous expression in tobacco enhanced its resistance against Phytophthora parasitica var. nicotianae, Alternaria alternata var. nicotianae and Rhizoctonia solani. Constitutive expression in peanut was associated with the co-expression of resistance-related genes, CC-NB-LRR and some protein kinases.


Assuntos
Arachis/citologia , Arachis/microbiologia , Resistência à Doença , Nicotiana/citologia , Nicotiana/microbiologia , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Arachis/genética , Arachis/imunologia , Morte Celular , Cruzamentos Genéticos , DNA Complementar/isolamento & purificação , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Filogenia , Phytophthora/fisiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Transporte Proteico , Reação em Cadeia da Polimerase em Tempo Real , Rhizoctonia/fisiologia , Transdução de Sinais , Frações Subcelulares/metabolismo , Nicotiana/genética , Transformação Genética , Transgenes
6.
Funct Integr Genomics ; 14(2): 307-17, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24615687

RESUMO

Usable male sterility systems have immense potential in developing hybrid varieties in crop plants, which can also be used as a biological safety containment to prevent horizontal transgene flow. Barnase-Barstar system developed earlier was the first approach to engineer male sterility in plants. In an analogous situation, we have evolved a system of inducing pollen abortion and male sterility in transgenic tobacco by expressing a plant gene coding for a protein with known developmental function in contrast to the Barnase-Barstar system, which deploys genes of prokaryotic origin, i.e., from Bacillus amyloliquefaciens. We have used a plant pathogen-induced gene, cysteine protease for inducing male sterility. This gene was identified in the wild peanut, Arachis diogoi differentially expressed when it was challenged with the late leaf spot pathogen, Phaeoisariopsis personata. Arachis diogoi cysteine protease (AdCP) was expressed under the strong tapetum-specific promoter (TA29) and tobacco transformants were generated. Morphological and histological analysis of AdCP transgenic plants showed ablated tapetum and complete pollen abortion in three transgenic lines. Furthermore, transcript analysis displayed the expression of cysteine protease in these male sterile lines and the expression of the protein was identified in western blot analysis using its polyclonal antibody raised in the rabbit system.


Assuntos
Cisteína Proteases/genética , Regulação da Expressão Gênica de Plantas , Nicotiana/genética , Infertilidade das Plantas/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Sequência de Aminoácidos , Arachis/genética , Arachis/microbiologia , Ascomicetos/patogenicidade , Ascomicetos/fisiologia , Cisteína Proteases/metabolismo , Dados de Sequência Molecular , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Pólen , Regiões Promotoras Genéticas , Alinhamento de Sequência , Nicotiana/enzimologia , Transgenes
7.
Front Plant Sci ; 14: 1275854, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023864

RESUMO

Peanut Arachis hypogaea is a segmental allotetraploid in the section Arachis of the genus Arachis along with the Section Rhizomataceae. Section Arachis has several diploid species along with Arachis hypogaea and A. monticola. The section Rhizomataceae comprises polyploid species. Several species in the genus are highly tolerant to biotic and abiotic stresses and provide excellent sets of genotypes for studies on differential gene expression. Though there were several studies in this direction, more studies are needed to identify more and more gene combinations. Next generation RNA-seq based differential gene expression study is a powerful tool to identify the genes and regulatory pathways involved in stress tolerance. Transcriptomic and proteomic study of peanut plants under biotic stresses reveals a number of differentially expressed genes such as R genes (NBS-LRR, LRR-RLK, protein kinases, MAP kinases), pathogenesis related proteins (PR1, PR2, PR5, PR10) and defense related genes (defensin, F-box, glutathione S-transferase) that are the most consistently expressed genes throughout the studies reported so far. In most of the studies on biotic stress induction, the differentially expressed genes involved in the process with enriched pathways showed plant-pathogen interactions, phenylpropanoid biosynthesis, defense and signal transduction. Differential gene expression studies in response to abiotic stresses, reported the most commonly expressed genes are transcription factors (MYB, WRKY, NAC, bZIP, bHLH, AP2/ERF), LEA proteins, chitinase, aquaporins, F-box, cytochrome p450 and ROS scavenging enzymes. These differentially expressed genes are in enriched pathways of transcription regulation, starch and sucrose metabolism, signal transduction and biosynthesis of unsaturated fatty acids. These identified differentially expressed genes provide a better understanding of the resistance/tolerance mechanism, and the genes for manipulating biotic and abiotic stress tolerance in peanut and other crop plants. There are a number of differentially expressed genes during biotic and abiotic stresses were successfully characterized in peanut or model plants (tobacco or Arabidopsis) by genetic manipulation to develop stress tolerance plants, which have been detailed out in this review and more concerted studies are needed to identify more and more gene/gene combinations.

8.
Wiley Interdiscip Rev RNA ; 14(3): e1763, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36131558

RESUMO

Splicing of pre-mRNA is an essential part of eukaryotic gene expression. Serine-/arginine-rich (SR) proteins are highly conserved RNA-binding proteins present in all metazoans and plants. SR proteins are involved in constitutive and alternative splicing, thereby regulating the transcriptome and proteome diversity in the organism. In addition to their role in splicing, SR proteins are also involved in mRNA export, nonsense-mediated mRNA decay, mRNA stability, and translation. Due to their pivotal roles in mRNA metabolism, SR proteins play essential roles in normal growth and development. Hence, any misregulation of this set of proteins causes developmental defects in both plants and animals. SR proteins from the animal kingdom are extensively studied for their canonical and noncanonical functions. Compared with the animal kingdom, plant genomes harbor more SR protein-encoding genes and greater diversity of SR proteins, which are probably evolved for plant-specific functions. Evidence from both plants and animals confirms the essential role of SR proteins as regulators of gene expression influencing cellular processes, developmental stages, and disease conditions. This article is categorized under: RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing.


Assuntos
Processamento Alternativo , Splicing de RNA , Animais , Precursores de RNA/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo
9.
Gene ; 828: 146468, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35390443

RESUMO

Sheath Blight (SB) disease in rice is caused by the infection from the fungal pathogen Rhizoctonia solani (R. solani). SB is one of the most severe rice diseases that can cause up to 50% yield losses in rice. Naturally occurring rice varieties resistant to SB have not been reported yet. We have performed a Time-Series RNA-Seq analysis on a widely cultivated rice variety BPT-5204 for identifying transcriptome level response signatures during R. solani infection at 1st, 2nd and 5th day post infection (dpi). In total, 428, 3225 and 1225 genes were differentially expressed in the treated rice plants on 1, 2 and 5 dpi, respectively. GO and KEGG enrichment analysis identified significant processes and pathways differentially altered in the rice plants during the fungal infection. Machine learning and network based integrative approach was used to construct rice Transcriptional Regulatory Networks (TRNs) for the three time points. TRN analysis identified SUB1B, MYB30 and CCA1 as important regulatory hub transcription factors in rice during R. solani infection. Jasmonic acid, salicylic acid, ethylene biogenesis and signaling were induced on infection. SAR was up regulated, while photosynthesis and carbon fixation processes were significantly down regulated. Involvement of MAPK, CYPs, peroxidase, PAL, chitinase genes were also observed in response to the fungal infection. The integrative analysis identified seven putative SB resistance genes differentially regulated in rice during R. solani infection.


Assuntos
Oryza , Resistência à Doença/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Oryza/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Rhizoctonia/genética , Transcriptoma
10.
Plant Mol Biol ; 75(4-5): 497-513, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21298396

RESUMO

The wild relatives of peanut are resistant to various economically important diseases including late leaf spot (LLS) caused by Phaeoisariopsis personata, compared with the susceptible cultivated peanut (Arachis hypogaea L.). The interaction of the late leaf spot pathogen, Phaeoisariopsis personata and the highly resistant, diploid peanut wild species, Arachis diogoi was analyzed at the molecular level by differential gene expression studies. Genes up-regulated with in 48 h of pathogen challenge were isolated as partial cDNAs. Some of the isolated genes, which are shown to be involved in the first line of defense in plants, were further characterized with respect to their transcriptional regulation in response to pathogen. Among the isolated clones, two were found to encode cyclophilin like proteins. One of the two isolated partial cDNAs encoding cyclophilin like proteins was extended using 5' RACE. The full length cDNA, designated as AdCyp, was 886 bp in length and encodes a polypeptide of 172 amino acids. Southern hybridization suggests that AdCyp is possibly coded by a single gene and at least one more identical gene is present in Arachis diogoi genome. AdCyp exhibits evolutionary conservation across the kingdoms. Phylogenetic analysis showed that AdCyp belongs to the subgroup I of Group I in cyclophilins. A translational fusion of GFP-AdCyp was found to localize to both cytosol and nucleus. AdCyp transcripts were found to accumulate in response to the treatments with pathogen as well as phytohormones. Constitutive heterologous expression of AdCyp resulted in enhanced resistance to Ralstonia solanacearum and reduced susceptibility towards Phytophthora parasitica var. nicotianae in transgenic tobacco and the resistance was associated with higher transcript levels of various defense related genes.


Assuntos
Arachis/genética , Arachis/microbiologia , Ascomicetos/patogenicidade , Ciclofilinas/biossíntese , Proteínas de Plantas/biossíntese , Sequência de Aminoácidos , Arachis/metabolismo , Ciclofilinas/genética , Expressão Gênica , Genes de Plantas , Interações Hospedeiro-Patógeno/genética , Dados de Sequência Molecular , Filogenia , Phytophthora/patogenicidade , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Ralstonia solanacearum/patogenicidade , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Homologia de Sequência de Aminoácidos , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/microbiologia
11.
Plant Sci ; 302: 110718, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33288024

RESUMO

Our previous study demonstrated that the expression of GhNAC4, a NAC transcription factor from cotton, was induced by abiotic stresses and abscisic acid (ABA). In the present study, we investigated the molecular mechanisms underlying ABA and stress response of GhNAC4. Overexpression of GhNAC4 in transgenic tobacco conferred tolerance to salinity and drought treatments with associated enhanced expression of several stress-responsive marker genes. GhNAC4 is a protein that is translocated to the nucleus where it exhibits transcriptional activation property and also forms homo-dimers. In this study, we also investigated the domains essential for the biochemical functions of GhNAC4. We developed transgenic tobacco plants overexpressing the GhNAC4 NAC-domain and the transcriptional regulatory (TR) domain separately. NAC-domain transgenics showed hypersensitivity to exogenous ABA while TR-domain transgenics exhibited reduced sensitivity. Abiotic stress assays indicated that transgenic plants expressing both the domains separately were more tolerant than wild type plants with the NAC-domain transgenics showing increased tolerance as compared to TR-domain transgenics. Expression analysis revealed that various stress-responsive genes were upregulated in both NAC-domain and TR-domain transgenics under salinity and drought treatments. These results suggest that the stress tolerance ability of GhNAC4 is associated with both the component domains while the ABA responsiveness is largely associated with N-terminal NAC-domain.


Assuntos
Ácido Abscísico/metabolismo , Gossypium/fisiologia , Reguladores de Crescimento de Plantas/fisiologia , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Clonagem Molecular , Dimerização , Gossypium/metabolismo , Peroxidação de Lipídeos , Mutagênese Sítio-Dirigida , Perfenazina/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Prolina/metabolismo , Estresse Fisiológico , Relação Estrutura-Atividade , Nicotiana , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
12.
Front Plant Sci ; 12: 777285, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899804

RESUMO

Our group has previously identified the activation of a GRAS transcription factor (TF) gene in the gain-of-function mutant population developed through activation tagging in rice (in an indica rice variety, BPT 5204) that was screened for water use efficiency. This family of GRAS transcription factors has been well known for their diverse roles in gibberellin signaling, light responses, root development, gametogenesis etc. Recent studies indicated their role in biotic and abiotic responses as well. Although this family of TFs received significant attention, not many genes were identified specifically for their roles in mediating stress tolerance in rice. Only OsGRAS23 (here named as OsGRAS22) was reported to code for a TF that induced drought tolerance in rice. In the present study, we have analyzed the expression patterns of rice GRAS TF genes under abiotic (NaCl and ABA treatments) and biotic (leaf samples infected with pathogens, Xanthomonas oryzae pv. oryzae that causes bacterial leaf blight and Rhizoctonia solani that causes sheath blight) stress conditions. In addition, their expression patterns were also analyzed in 13 different developmental stages. We studied their spatio-temporal regulation and correlated them with the in-silico studies. Fully annotated genomic sequences available in rice database have enabled us to study the protein properties, ligand interactions, domain analysis and presence of cis-regulatory elements through the bioinformatic approach. Most of the genes were induced immediately after the onset of stress particularly in the roots of ABA treated plants. OsGRAS39 was found to be a highly expressive gene under sheath blight infection and both abiotic stress treatments while OsGRAS8, OsSHR1 and OsSLR1 were also responsive. Our earlier activation tagging based functional characterization followed by the genome-wide characterization of the GRAS gene family members in the present study clearly show that they are highly appropriate candidate genes for manipulating stress tolerance in rice and other crop plants.

13.
Plant Cell Physiol ; 50(3): 541-53, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19179349

RESUMO

Protease inhibitors have been reported to confer insect resistance in transgenic plants, except for a rice protease inhibitor that conferred drought tolerance in transgenic rice plants. We have cloned a protease inhibitor of tobacco that is expressed under treatment with ABA, hydrogen peroxide, methyl jasmonate and wounding. The cDNA codes for a six-domain serine protease inhibitor with a deduced sequence of 396 amino acids. We have generated transgenic tobacco plants expressing the protease inhibitor constitutively under the 35S promoter. When analyzed in the T(2) generation, these transgenic plants exhibited tolerance to sodium chloride, variable pH and sorbitol, together with the expected resistance to the insect pests Spodoptera litura and Helicoverpa armigera. The transgenic plants showed enhanced seed germination, root length and root-shoot ratio, significantly enhanced total chlorophyll content and reduced thiobarbituric acid-reactive substances under stress. Under sodium chloride treatment, the transgenic plants have enhanced protease inhibitor activity. The transgenic plants exhibited a higher potassium content and an optimum Na+/K+ ratio. To our knowledge, this is the first report of transgenic plants with constitutive protease inhibitor expression showing tolerance to a wide range variable pH in the culture medium along with other stresses.


Assuntos
Nicotiana/genética , Proteínas de Plantas/metabolismo , Inibidores da Tripsina/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Fases de Leitura Aberta , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Potássio/análise , RNA de Plantas/genética , Plantas Tolerantes a Sal/genética , Plantas Tolerantes a Sal/metabolismo , Análise de Sequência de DNA , Sódio/análise , Estresse Fisiológico , Nicotiana/metabolismo , Inibidores da Tripsina/genética
14.
Biochem Biophys Res Commun ; 390(3): 427-33, 2009 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-19766095

RESUMO

NF-kappaB activity is tightly regulated by IkappaB class of proteins. IkappaB proteins possess ankyrin repeats for binding to and inhibiting NF-kappaB. The regulatory protein, NPR1 from Brassica juncea possesses ankyrin repeats with sequence similarity to IkappaBalpha subgroup. Therefore, we examined whether stably expressed BjNPR1 could function as IkappaB in inhibiting NF-kappaB in human glioblastoma cell lines. We observed that BjNPR1 bound to NF-kappaB and inhibited its nuclear translocation. Further, BjNPR1 expression down-regulated the NF-kappaB target genes iNOS, Cox-2, c-Myc and cyclin D1 and reduced the proliferation rate of U373 cells. Finally, BjNPR1 decreased the levels of pERK, pJNK and PKCalpha and increased the Caspase-3 and Caspase-8 activities. These results suggested that inhibition of NF-kappaB activation by BjNPR1 can be a promising therapy in NF-kappaB dependent pathologies.


Assuntos
Proteínas I-kappa B/metabolismo , Mostardeira/metabolismo , NF-kappa B/antagonistas & inibidores , Proteínas de Plantas/metabolismo , Transporte Ativo do Núcleo Celular , Sequência de Aminoácidos , Repetição de Anquirina , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/genética , Ciclo-Oxigenase 2/genética , Regulação para Baixo , Expressão Gênica , Regulação da Expressão Gênica , Genes Reporter , Humanos , Proteínas I-kappa B/genética , Inflamação/terapia , Dados de Sequência Molecular , Mostardeira/genética , NF-kappa B/metabolismo , Neoplasias/terapia , Óxido Nítrico Sintase Tipo II/genética , Proteínas de Plantas/genética , Proteína Quinase C-alfa/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , eIF-2 Quinase/metabolismo
15.
Mol Genet Genomics ; 282(1): 65-81, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19352711

RESUMO

Mitogen-activated protein kinase cascade plays a very important role in plant signal transduction mechanism. A full length cDNA of 1,514 bp length, corresponding to a mitogen-activated protein kinase gene was cloned from peanut (Arachis hypogaea). Based on its high homology with Arabidopsis AtMPK3, the cDNA was designated as AhMPK3. It carried an open reading frame of 1,113 bp encoding a 371 amino acid polypeptide. AhMPK3 bears TEY motif in its activation loop and belongs to the A1 subgroup of MAPK family. Southern blot analysis revealed that AhMPK3 exists in two copies in peanut genome and its structural organization revealed well-conserved nature of these signaling components across different species. AhMPK3 when transiently expressed in tobacco leaves was found to localize in both nucleus and cytoplasm. Transgenic tobacco plants ectopically expressing AhMPK3 exhibited enhanced resistance to first and second instar larvae of Spodoptera litura and constitutively higher transcript levels of defense response genes like PR1a, PR1b, LOX1, PI-II etc. Apart from this when wounded, transgenic plants accumulated high levels of PI-II and PR1b transcripts rapidly compared to wild type indicating the occurrence of a priming phenomenon.


Assuntos
Arachis/enzimologia , Arachis/genética , Genes de Plantas , Proteínas Quinases Ativadas por Mitógeno/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Primers do DNA/genética , DNA Complementar/genética , DNA de Plantas/genética , Dosagem de Genes , Expressão Gênica , Genoma de Planta , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Filogenia , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Plantas Geneticamente Modificadas , Homologia de Sequência de Aminoácidos , Spodoptera/patogenicidade , Nicotiana/enzimologia , Nicotiana/genética , Nicotiana/parasitologia
17.
Physiol Plant ; 133(4): 765-75, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18397206

RESUMO

In Arabidopsis, NPR1 (AtNPR1) regulates salicylic acid (SA)-mediated activation of PR genes at the onset of systemic acquired resistance. AtNPR1 also modulates SA-induced suppression of jasmonic acid-responsive gene expression, and npr1 mutants manifest enhanced herbivore resistance. We have raised stable transgenic tobacco lines, expressing AtNPR1 constitutively, which showed elevated expression of PR1 and PR2 genes upon SA treatment. Herbivore bioassays with a generalist polyphagous pest, Spodoptera litura, revealed that the transgenic lines exhibited enhanced resistance compared to the wild-type plants, particularly with respect to younger larval populations. Insect-mediated injury induced several protease inhibitors (PIs), more significantly a 40-kDa serine PI in all the tobacco lines, but the induction was higher in the transgenic plants. We show in this communication that heterologous expression of AtNPR1 provides enhanced resistance to early larval populations of the herbivore, Spodoptera in transgenic tobacco plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Nicotiana/genética , Nicotiana/parasitologia , Doenças das Plantas/imunologia , Doenças das Plantas/parasitologia , Spodoptera/fisiologia , Animais , Bioensaio , Comportamento Alimentar/efeitos dos fármacos , Trato Gastrointestinal/enzimologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Imunidade Inata/efeitos dos fármacos , Larva/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/parasitologia , Plantas Geneticamente Modificadas , Inibidores de Proteases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ácido Salicílico/farmacologia , Spodoptera/efeitos dos fármacos , Nicotiana/imunologia
18.
Plant Physiol Biochem ; 46(12): 1019-30, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18768323

RESUMO

Plant annexins belong to a multigene family and are suggested to play a role in stress responses. A full-length cDNA for a gene encoding an annexin protein was isolated and characterized from Brassica juncea (AnnBj1). AnnBj1 message levels were regulated by abscisic acid, ethephon, salicylic acid, and methyl jasmonate as well as chemicals that induce osmotic stress (NaCl, Mannitol or PEG), heavy metal stress (CdCl(2)) and oxidative stress (methyl viologen or H(2)O(2)). In order to determine if AnnBj1 functions in protection against stress, we generated transgenic tobacco plants ectopically expressing AnnBj1 under the control of constitutive CaMV 35S promoter. The transgenic tobacco plants showed significant tolerance to dehydration (mannitol), salt (NaCl), heavy metal (CdCl(2)) and oxidative stress (H(2)O(2)) at the seedling stage and retained higher chlorophyll levels in response to the above stresses as determined in detached leaf senescence assays. The transgenic plants also showed decreased accumulation of thiobarbituric acid-reactive substances (TBARS) compared to wild-type plants in response to mannitol treatments in leaf disc assays. AnnBj1 recombinant protein exhibited low levels of peroxidase activity in vitro and transgenic plants showed increased total peroxidase activity. Additionally, the transgenic plants showed enhanced resistance to the oomycete pathogen, Phytophthora parasitica var. nicotianae, and increased message levels for several pathogenesis-related proteins. Our results demonstrate that ectopic expression of AnnBj1 in tobacco provides tolerance to a variety of abiotic and biotic stresses.


Assuntos
Adaptação Fisiológica , Anexinas/fisiologia , Brassica/genética , Nicotiana/fisiologia , Estresse Oxidativo , Plantas Geneticamente Modificadas/fisiologia , Anexinas/genética , Sequência de Bases , Clonagem Molecular , Primers do DNA , DNA Complementar , Peroxidases/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Nicotiana/enzimologia
19.
J Plant Physiol ; 164(3): 238-52, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16542753

RESUMO

A full-length 910bp cDNA encoding osmotin-like protein with an open reading frame of 744bp encoding a protein of 247 amino acids with a calculated molecular mass of 26.8kDa was cloned from Solanum nigrum (SniOLP). Phylogenetic analysis revealed the evolutionary conservation of this protein among diverse taxa. The genomic DNA gel blot showed that SniOLP belongs to a small multigene family and it showed organ-specific expression. Time-course studies revealed that the expression of SniOLP was upregulated by treatment with various signaling molecules, osmotic and oxidative stress inducers. Recombinant protein purified from overexpressed Escherichia coli cells showed hyphal growth inhibition in Rhizoctonia batiticola and Sclerotinia sclerotiorum but without any endo-beta-1,3-glucanase activity. Model built by homology modeling showed that the protein consists of an acidic cleft region that is capable of interacting with the carbohydrate components of the fungal cell walls. Analysis of the structure and functional relationship was carried out by docking of the beta-(1,3)-glucan onto the acidic cleft region on the surface of the protein (SniOLP).


Assuntos
Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Solanum nigrum/metabolismo , Adaptação Fisiológica , Sequência de Aminoácidos , Evolução Biológica , Endo-1,3(4)-beta-Glucanase/análise , Fungicidas Industriais/análise , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Dados de Sequência Molecular , Pressão Osmótica , Oxirredução , Folhas de Planta/química , Proteínas de Plantas/química , Análise de Sequência de DNA , Transdução de Sinais , Solanum nigrum/química , Homologia Estrutural de Proteína , Relação Estrutura-Atividade
20.
Mol Biotechnol ; 59(9-10): 445-457, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28791615

RESUMO

Usable pollination control systems have proven to be effective system for the development of hybrid crop varieties, which are important for optimal performance over varied environments and years. They also act as a biocontainment to check horizontal transgene flow. In the last two decades, many genetic manipulations involving genes controlling the production of cytotoxic products, conditional male sterility, altering metabolic processes, post-transcriptional gene silencing, RNA editing and chloroplast engineering methods have been used to develop a proper pollination control system. In this review article, we outline the approaches used for generating male sterile plants using an effective pollination control system to highlight the recent progress that occurred in this area. Furthermore, we propose possible future directions for biotechnological improvements that will allow the farmers to buy hybrid seed once for many generations in a cost-effective manner.


Assuntos
Fertilidade/genética , Infertilidade das Plantas/genética , Plantas Geneticamente Modificadas/genética , Pólen/genética , Sementes/genética , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento , Transgenes/genética
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