Ratio of mutated versus wild-type coat protein sequences inPepino mosaic virusdetermines the nature and severity of yellowing symptoms on tomato plants

The first line of plant defence responses against pathogens can be induced by the bacterial flg22 and can be dependent on various external and internal factors. Here, we firstly studied the effects of daytime and ethylene (ET) using Never ripe (Nr) mutants in the local and systemic defence responses of intact tomato plants after flg22 treatments. Flg22 was applied in the afternoon and at night and rapid reactions were detected. The production of hydrogen peroxide and nitric oxide was induced by flg22 locally, while superoxide was induced systemically, in wild type plants in the light period, but all remained lower at night and in Nr leaves. Flg22 elevated, locally, the ET, jasmonic acid (JA) and salicylic acid (SA) levels in the light period; these levels did not change significantly at night. Expression of Pathogenesis-related 1 (PR1), Ethylene response factor 1 (ERF1) and Defensin (DEF) showed also daytime- and ET-dependent changes. Enhanced ERF1 and DEF expression and stomatal closure were also observable in systemic leaves of wild type plants in the light. These data demonstrate that early biotic signalling in flg22-treated leaves and distal ones is an ET-dependent process and it is also determined by the time of day and inhibited in the early night phase.

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Comparison ofEnt-kaurene synthetase A and B activities in cell-free extracts from young tomato fruits of wild-type andgib-1, gib-2, andgib-3 tomato plants

Journal of Plant Growth Regulation ◽

10.1007/bf02041969 ◽

1990 ◽

Vol 9 (1-4) ◽

pp. 237-242 ◽

Cited By ~ 32

Author(s):

R. J. Bensen ◽

J. A. D. Zeevaart

Keyword(s):

Wild Type ◽

Tomato Fruits ◽

Tomato Plants

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Identification of a DNA region required for growth of Pseudomonas syringae pv. tomato on tomato plants

Canadian Journal of Microbiology ◽

10.1139/m92-144 ◽

1992 ◽

Vol 38 (9) ◽

pp. 883-890 ◽

Cited By ~ 2

Author(s):

Dennis P. Jackson ◽

Douglas A. Gray ◽

Vincent L. Morris ◽

Diane A. Cuppels

Keyword(s):

Organic Acids ◽

Pseudomonas Syringae ◽

Acid Metabolism ◽

Carbon Sources ◽

Hypersensitive Reaction ◽

Wild Type ◽

In Planta ◽

Tomato Plants ◽

Tartaric Acids ◽

Nonpathogenic Strain

The prototrophic Pseudomonas syringae pv. tomato mutant DC3481, which is the result of a single-site Tn5 insertion, cannot grow and cause disease on tomato plants and cannot use the major organic acids of tomato, i.e., citric, malic, succinic, and tartaric acids, as sole carbon sources. Although nonpathogenic, strain DC3481 can still induce a hypersensitive reaction in nonhost plants. We have identified a 30-kb fragment of P. syringae pv. tomato wild-type DNA that can complement this mutant. EcoRI fragments from this region were subcloned and individually subjected to functional complementation analysis. The 3.8-kb fragment, which was the site of the Tn5 insertion, restored pathogenicity and the ability to use all the major organic acids of tomato as carbon sources. It shares sequence homology with several P. syringae pathovars but not other bacterial tomato pathogens. Our results indicate that sequences on the 3.8-kb EcoRI fragment are required for both the ability to grow on tomato leaves (and thus cause disease) and the utilization of carboxylic acids common to tomato. The 3.8-kb fragment may contain a sequence (or sequences) that regulates both traits. Key words: Pseudomonas syringae pv. tomato, phytopathogenicity, Tn5, tricarboxylic acid metabolism, bacterial speck, growth in planta.

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Comparative reactions of recombinant papaya ringspot viruses with chimeric coat protein (CP) genes and wild-type viruses on CP-transgenic papaya

Journal of General Virology ◽

10.1099/0022-1317-82-11-2827 ◽

2001 ◽

Vol 82 (11) ◽

pp. 2827-2836 ◽

Cited By ~ 32

Author(s):

Chu-Hui Chiang ◽

Ju-Jung Wang ◽

Fuh-Jyh Jan ◽

Shyi-Dong Yeh ◽

Dennis Gonsalves

Keyword(s):

Coat Protein ◽

Sequence Similarity ◽

Transcriptional Gene Silencing ◽

Papaya Ringspot Virus ◽

Wild Type ◽

Coding Region ◽

Transgenic Papaya ◽

Cp Gene ◽

Post Transcriptional Gene Silencing

Transgenic papaya cultivars SunUp and Rainbow express the coat protein (CP) gene of the mild mutant of papaya ringspot virus (PRSV) HA. Both cultivars are resistant to PRSV HA and other Hawaii isolates through homology-dependent resistance via post-transcriptional gene silencing. However, Rainbow, which is hemizygous for the CP gene, is susceptible to PRSV isolates from outside Hawaii, while the CP-homozygous SunUp is resistant to most isolates but susceptible to the YK isolate from Taiwan. To investigate the role of CP sequence similarity in overcoming the resistance of Rainbow, PRSV HA recombinants with various CP segments of the YK isolate were constructed and evaluated on Rainbow, SunUp and non-transgenic papaya. Non-transgenic papaya were severely infected by all recombinants, but Rainbow plants developed a variety of symptoms. On Rainbow, a recombinant with the entire CP gene of YK caused severe symptoms, while recombinants with only partial YK CP sequences produced a range of milder symptoms. Interestingly, a recombinant with a YK segment from the 5′ region of the CP gene caused very mild, transient symptoms, whereas recombinants with YK segments from the middle and 3′ parts of the CP gene caused prominent and lasting symptoms. SunUp was resistant to all but two recombinants, which contained the entire CP gene or the central and 3′-end regions of the CP gene and the 3′ non-coding region of YK, and the resulting symptoms were mild. It is concluded that the position of the heterologous sequences in the recombinants influences their pathogenicity on Rainbow.

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Glutathione Status in the Roots of Tomato Plants Transgenic by Genes psl and rapA1 in the Presence of Rhizobium leguminosarum

Russian Journal of Plant Physiology ◽

10.1134/s1021443721050228 ◽

2021 ◽

Vol 68 (5) ◽

pp. 923-930

Author(s):

Z. R. Vershinina ◽

O. V. Chubukova ◽

D. R. Maslennikova

Keyword(s):

Solanum Lycopersicum ◽

Bacterial Adhesion ◽

Rhizobium Leguminosarum ◽

De Novo ◽

Growth Parameters ◽

Wild Type ◽

Leguminous Plants ◽

Tomato Plants ◽

Glutathione Status

Abstract The level of glutathione was investigated in the roots of tomato (Solanum lycopersicum L.) plants transgenic by genes psl and rapA1 in the presence of a microsymbiont of leguminous plants Rhizobium leguminosarum VSy3. The plants transformed with gene psl showed a greater bacterial adhesion than the plants transformed with gene rapA1, which positively correlated with growth parameters of plants. Treatment with rhizobia elevated the content of glutathione in the roots of wild type plants three times, 4.7 times in the roots of plants transformed with gene rapA1, and more than five times in the plants transgenic by gene psl. The obtained results suggest that the level of glutathione in the roots may serve as a marker of efficiency of artificial symbiotic systems produced de novo.

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Solvent Accessibility of Residues Undergoing Pathogenic Variations in Humans: From Protein Structures to Protein Sequences

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2020.626363 ◽

2021 ◽

Vol 7 ◽

Author(s):

Castrense Savojardo ◽

Matteo Manfredi ◽

Pier Luigi Martelli ◽

Rita Casadio

Keyword(s):

Solvent Accessibility ◽

Protein Structures ◽

Three Dimensional ◽

Protein Sequences ◽

Large Data ◽

Human Protein ◽

Dimensional Structure ◽

Wild Type ◽

Solvent Exposure ◽

Data Set

Solvent accessibility (SASA) is a key feature of proteins for determining their folding and stability. SASA is computed from protein structures with different algorithms, and from protein sequences with machine-learning based approaches trained on solved structures. Here we ask the question as to which extent solvent exposure of residues can be associated to the pathogenicity of the variation. By this, SASA of the wild-type residue acquires a role in the context of functional annotation of protein single-residue variations (SRVs). By mapping variations on a curated database of human protein structures, we found that residues targeted by disease related SRVs are less accessible to solvent than residues involved in polymorphisms. The disease association is not evenly distributed among the different residue types: SRVs targeting glycine, tryptophan, tyrosine, and cysteine are more frequently disease associated than others. For all residues, the proportion of disease related SRVs largely increases when the wild-type residue is buried and decreases when it is exposed. The extent of the increase depends on the residue type. With the aid of an in house developed predictor, based on a deep learning procedure and performing at the state-of-the-art, we are able to confirm the above tendency by analyzing a large data set of residues subjected to variations and occurring in some 12,494 human protein sequences still lacking three-dimensional structure (derived from HUMSAVAR). Our data support the notion that surface accessible area is a distinguished property of residues that undergo variation and that pathogenicity is more frequently associated to the buried property than to the exposed one.

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Pyramiding Unmarked Deletions in Ralstonia solanacearum Shows That Secreted Proteins in Addition to Plant Cell-Wall-Degrading Enzymes Contribute to Virulence

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-18-1296 ◽

2005 ◽

Vol 18 (12) ◽

pp. 1296-1305 ◽

Cited By ~ 77

Author(s):

Huanli Liu ◽

Shuping Zhang ◽

Mark A. Schell ◽

Timothy P. Denny

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Ralstonia Solanacearum ◽

Plant Cell Wall ◽

Secreted Proteins ◽

Cellulolytic Enzymes ◽

Wild Type ◽

Cell Wall Degrading Enzymes ◽

Tomato Plants ◽

Degrading Enzymes

Ralstonia solanacearum, like many phytopathogenic bacteria, makes multiple extracellular plant cell-wall-degrading enzymes (CWDE), some of which contribute to its ability to cause wilt disease. CWDE and many other proteins are secreted to the milieu via the highly conserved type II protein secretion system (T2SS). R. solanacearum with a defective T2SS is weakly virulent, but it is not known whether this is due to absence of all the CWDE or the loss of other secreted proteins that contribute to disease. These alternatives were investigated by creating mutants of wild-type strain GMI1000 lacking either the T2SS or up to six CWDE and comparing them for virulence on tomato plants. To create unmarked deletions, genomic regions flanking the target gene were polymerase chain reaction (PCR)-amplified, were fused using splice overlap extension PCR, were cloned into a suicide plasmid harboring the sacB counter-selectable marker, and then, were site-specifically introduced into the genome. Various combinations of five deletions (δpehA, δpehB, δpehC, δpme, and δegl) and one inactivated allele (cbhA::aphA-3) resulted in 15 mutants missing one to six CWDE. In soil-drench inoculation assays, virulence of mutants lacking only pectic enzymes (PehA, PehB, PehC, and Pme) was not statistically different from GMI1000, but all the mutants lacking one or both cellulolytic enzymes (Egl or CbhA) wilted plants significantly more slowly than did the wild type. The GMI-6 mutant that lacks all six CWDE was more virulent than the mutant lacking only its two cellulolytic enzymes, and both were significantly more virulent than the T2SS mutant (GMI-D). Very similar results were observed in wounded-petiole inoculation assays, so GMI-6 and GMI-D appear to be less capable of colonizing tomato tissues after invasion. Because the T2SS mutant was much less virulent than the sixfold CWDE mutant, we conclude that other secreted proteins contribute substantially to the ability of R. solanacearum GMI1000 to systemically colonize tomato plants.

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Disruption of aldA Influences the Developmental Process in Myxococcus xanthus

Journal of Bacteriology ◽

10.1128/jb.182.2.546-550.2000 ◽

2000 ◽

Vol 182 (2) ◽

pp. 546-550 ◽

Cited By ~ 10

Author(s):

Mandy J. Ward ◽

Helen Lew ◽

David R. Zusman

Keyword(s):

Gene Disruption ◽

Minimal Medium ◽

Developmental Process ◽

Myxococcus Xanthus ◽

Protein Sequences ◽

Rich Medium ◽

Wild Type ◽

Rate Of Growth ◽

Alanine Dehydrogenase ◽

Developmental Conditions

ABSTRACT Previously, we identified a gene (aldA) fromMyxococcus xanthus, which we suggested encoded the enzyme alanine dehydrogenase on the basis of similarity to known Ald protein sequences (M. J. Ward, H. Lew, A. Treuner-Lange, and D. R. Zusman, J. Bacteriol. 180:5668–5675, 1998). In this study, we have confirmed that aldA does encode a functional alanine dehydrogenase, since it catalyzes the reversible conversion of alanine to pyruvate and ammonia. Whereas an aldA gene disruption mutation did not significantly influence the rate of growth or spreading on a rich medium, AldA was required for growth on a minimal medium containing l-alanine as the major source of carbon. Under developmental conditions, the aldA mutation caused delayed aggregation in both wild-type (DZ2) and FB (DZF1) strains. Poorly formed aggregates and reduced levels of spores were apparent in the DZ2 aldA mutant, even after prolonged development.

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Sulfite Oxidase Activity Level Determines the Sulfite Toxicity Effect in Leaves and Fruits of Tomato Plants

Agronomy ◽

10.3390/agronomy10050694 ◽

2020 ◽

Vol 10 (5) ◽

pp. 694

Author(s):

Umanath Sharma ◽

Aizat Bekturova ◽

Yvonne Ventura ◽

Moshe Sagi

Keyword(s):

Sulfite Oxidase ◽

Activity Level ◽

Vegetable Crops ◽

Plant Tolerance ◽

Wild Type ◽

Biotic And Abiotic Stresses ◽

Tomato Plants ◽

Leaf Discs ◽

Toxicity Effect ◽

Treated Leaf

Increasing plant tolerance to sulfites/SO2 can lead to the development of tolerant crops to biotic and abiotic stresses. Plant sulfite oxidase (SO) is a molybdo-enzyme that oxidizes excess SO2/sulfite into non-toxic sulfate. The effect of toxic sulfite on leaves and fruits was studied in tomato plants with different SO expression: wild-type, SO overexpression (OE) and SO RNA interference (Ri). Sulfite-dipped ripe-fruits and sulfite treated leaf discs of Ri plants impaired in SO activity were more susceptible, whereas OE plants were more resistant, as revealed by remaining chlorophyll and tissue damage levels. Application of molybdenum further enhanced the tolerance of leaf discs to sulfite by enhancing SO activity in OE lines, but not in wild-type or Ri plants. Notably, incubation with tungsten, the molybdenum antagonist, overturned the effect of molybdenum spray in OE plants, revealed by remaining chlorophyll content and SO activity. The results indicate that SO in tomato leaves and ripe fruits determines the resistance to sulfite and the application of molybdenum enhances sulfite resistance in OE plants by increasing SO activity. Overall, the results suggest that SO overexpression can be employed, with or without molybdenum application, for developing fruit and vegetable crops tolerant to sulfite/SO2 containing pre- and postharvest treatments.

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Restoration of Wild-Type Virus by Double Recombination of Tombusvirus Mutants with a Host Transgene

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.1999.12.2.153 ◽

1999 ◽

Vol 12 (2) ◽

pp. 153-162 ◽

Cited By ~ 50

Author(s):

Marise Borja ◽

Teresa Rubio ◽

Herman B. Scholthof ◽

Andrew O. Jackson

Keyword(s):

Coat Protein ◽

Transgenic Plants ◽

Coat Protein Gene ◽

Protein Gene ◽

Wild Type Virus ◽

Type Virus ◽

Virus Infections ◽

Wild Type ◽

Transgenic Lines ◽

Double Recombination

Nicotiana benthamiana plants transformed with the coat protein gene of tomato bushy stunt virus (TBSV) failed to elicit effective virus resistance when inoculated with wild-type virus. Subsequently, R1 and R2 progeny from 13 transgenic lines were inoculated with a TBSV mutant containing a defective coat protein gene. Mild symptoms typical of those elicited in nontransformed plants infected with the TBSV mutant initially appeared. However, within 2 to 4 weeks, up to 20% of the transgenic plants sporadically began to develop the lethal syndrome characteristic of wild-type virus infections. RNA hybridization and immunoblot analyses of these plants and nontransformed N. benthamiana inoculated with virus from the transgenic lines indicated that wild-type virus had been regenerated by a double recombination event between the defective virus and the coat protein transgene. Similar results were obtained with a TBSV deletion mutant containing a nucleotide sequence marker, and with a chimeric cucumber necrosis virus (CNV) containing the defective TBSV coat protein gene. In both cases, purified virions contained wild-type TBSV RNA or CNV chimeric RNA derived by recombination with the transgenic coat protein mRNA. These results thus demonstrate that recombinant tombusviruses can arise frequently from viral genes expressed in transgenic plants.

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