Azospirillum brasilense stimulate the growth in Arabidopsis thaliana through the target of rapamycin protein

Azospirillum spp., one of the best studied genus of plant growth promoting rhizobacteria. These rhizobacteria are able to colonize hundreds of plant species and improve their growth, development and productivity. The target of rapamycin (TOR) protein is a central component of the TOR signaling pathway, which regulates cell growth and metabolism in response to environment cues in eukaryotes. In this study, the TOR function was analyzed in Arabidopsis thaliana L. plants inoculated with the rhizobacteria Azospirillum brasilense. Arabidopsis seedlings tor-es, which express an interference RNA in presence of estradiol and decrease TOR expression, showed an inhibition in the growth and lateral root formation, with or without 1x102 CFU/mL of the inoculum. In addition, a morphological analysis of the root showed an inhibition in the root hair formation. The results suggest that A. brasilense controls A. thaliana growth through TOR signaling pathway.

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Photoperiod and temperature separately regulate nymphal development through JH and insulin/TOR signaling pathways in an insect

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1922747117 ◽

2020 ◽

Vol 117 (10) ◽

pp. 5525-5531 ◽

Cited By ~ 1

Author(s):

Taiki Miki ◽

Tsugumichi Shinohara ◽

Silvia Chafino ◽

Sumihare Noji ◽

Kenji Tomioka

Keyword(s):

Growth Rate ◽

Juvenile Hormone ◽

Signaling Pathway ◽

Slow Growth ◽

Physiological State ◽

Target Of Rapamycin ◽

Tor Signaling ◽

Seasonal Adaptation ◽

Nymphal Stage ◽

Nymphal Development

Insects living in the temperate zone enter a physiological state of arrested or slowed development to overcome an adverse season, such as winter. Developmental arrest, called diapause, occurs at a species-specific developmental stage, and embryonic and pupal diapauses have been extensively studied in mostly holometabolous insects. Some other insects overwinter in the nymphal stage with slow growth for which the mechanism is poorly understood. Here, we show that this nymphal period of slow growth is regulated by temperature and photoperiod through separate pathways in the cricket Modicogryllus siamensis. The former regulates the growth rate, at least in part, through the insulin / target of rapamycin (TOR) signaling pathway. Lower temperature down-regulates the expression of insulin-like peptide (Ms’Ilp) and Target of rapamycin (Ms’Tor) genes to slow down the growth rate without affecting the number of molts. The latter regulates the number of molts independent of temperature. Short days increase the number of molts through activation of the juvenile hormone (JH) pathway and down-regulation of myoglianin (Ms’myo), a member of the TGFβ family, which induces adult metamorphosis. In contrast, long days regulate Ms’myo expression to increase during the fifth to sixth instar to initiate adult metamorphosis. When Ms’myo expression is suppressed, juvenile hormone O-methyl transferase (Ms’jhamt) was up-regulated and increased molts to prolong the nymphal period even under long-day conditions. The present findings suggested that the photoperiod regulated Ms’myo, and the JH signaling pathway and the temperature-controlled insulin/TOR pathway cooperated to regulate nymphal development for overwintering to achieve seasonal adaptation of the life cycle in M. siamensis.

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The Target of Rapamycin Signaling Pathway Regulates mRNA Turnover in the YeastSaccharomyces cerevisiae

Molecular Biology of the Cell ◽

10.1091/mbc.12.11.3428 ◽

2001 ◽

Vol 12 (11) ◽

pp. 3428-3438 ◽

Cited By ~ 44

Author(s):

Allan R. Albig ◽

Carolyn J. Decker

Keyword(s):

Signaling Pathway ◽

Mrna Decay ◽

Prolonged Exposure ◽

Specific Inhibitor ◽

Target Of Rapamycin ◽

Mrna Turnover ◽

Diauxic Shift ◽

Nutrient Depletion ◽

Tor Signaling ◽

Tor Pathway

The target of rapamycin (TOR) signaling pathway is an important mechanism by which cell growth is regulated by nutrient availability in eukaryotes. We provide evidence that the TOR signaling pathway controls mRNA turnover in Saccharomyces cerevisiae. During nutrient limitation (diauxic shift) or after treatment with rapamycin (a specific inhibitor of TOR), multiple mRNAs were destabilized, whereas the decay of other mRNAs was unaffected. Our findings suggest that the regulation of mRNA decay by the TOR pathway may play a significant role in controlling gene expression in response to nutrient depletion. The inhibition of the TOR pathway accelerated the major mRNA decay mechanism in yeast, the deadenylation-dependent decapping pathway. Of the destabilized mRNAs, two different responses to rapamycin were observed. Some mRNAs were destabilized rapidly, while others were affected only after prolonged exposure. Our data suggest that the mRNAs that respond rapidly are destabilized because they have short poly(A) tails prematurely either as a result of rapid deadenylation or reduced polyadenylation. In contrast, the mRNAs that respond slowly are destabilized by rapid decapping. In summary, the control of mRNA turnover by the TOR pathway is complex in that it specifically regulates the decay of some mRNAs and not others and that it appears to control decay by multiple mechanisms.

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Mitochondrial β-Cyanoalanine Synthase Is Essential for Root Hair Formation in Arabidopsis thaliana

The Plant Cell ◽

10.1105/tpc.110.076828 ◽

2010 ◽

Vol 22 (10) ◽

pp. 3268-3279 ◽

Cited By ~ 59

Author(s):

Irene García ◽

José María Castellano ◽

Blanca Vioque ◽

Roberto Solano ◽

Cecilia Gotor ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Root Hair ◽

Root Hair Formation ◽

Cyanoalanine Synthase ◽

Hair Formation

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Characterization of Selected Plant Growth-Promoting Rhizobacteria and Their Non-Host Growth Promotion Effects

Microbiology Spectrum ◽

10.1128/spectrum.00279-21 ◽

2021 ◽

Author(s):

Di Fan ◽

Donald L. Smith

Keyword(s):

Arabidopsis Thaliana ◽

Plant Growth ◽

Plant Growth Promotion ◽

Growth Promotion ◽

Plant Growth Promoting Rhizobacteria ◽

Content Type ◽

Host Growth ◽

Plant Growth Promoting ◽

Growth Promoting

There are pressing needs to reduce the use of agrochemicals, and PGPR are receiving increasing interest in plant growth promotion and disease protection. This study follows up our previous report that the four newly isolated rhizobacteria promote the growth of Arabidopsis thaliana .

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Effects of Durum Wheat (Triticum durum Desf.) Inoculation with PGPR (Azospirillum brasilense, Bacillus sp and Frankia CcI3) and Its Tolerance to Water Deficit

Indian Journal of Agricultural Research ◽

10.18805/ijare.a-516 ◽

2020 ◽

Author(s):

M. Benmati ◽

A. Mouellef ◽

N. Belbekri ◽

A. Djekoun

Keyword(s):

Plant Growth ◽

Durum Wheat ◽

Water Deficit ◽

Azospirillum Brasilense ◽

Plant Growth Promoting Rhizobacteria ◽

Bacillus Sp ◽

Wheat Varieties ◽

Plant Growth Promoting ◽

Underlying Mechanisms ◽

Eastern Algeria

Plant-growth-promoting rhizobacteria can improve plant growth, development and stress adaptation. However, the underlying mechanisms are still largely unclear. We investigated the effects of Azospirillum brasilense, Bacillus sp and Frankia CcI3 on durum wheat. Our study consisted in the evaluation of the interaction between rhizosphere microorganisms isolated from soils of different regions of Eastern Algeria and two varieties of durum wheat (GTA- dur and WAHA). Furthermore, our studies have also been carried out on the same durum wheat varieties under water deficit condition for the evaluation of the capacities of these PGPR in the restoration of their growth and in the increase of the production. The obtained results confirm the significant abilities of PGPR under these stress conditions for maintaining growth and plant survival.

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Arabidopsis thaliana: a model for studies of colonization by non-pathogenic and plant-growth-promoting rhizobacteria

Functional Plant Biology ◽

10.1071/pp01048 ◽

2001 ◽

Vol 28 (9) ◽

pp. 975

Author(s):

Kenneth J. O'Callaghan ◽

Richard A. Dixon ◽

Edward C. Cocking

Keyword(s):

Arabidopsis Thaliana ◽

Plant Growth ◽

Stress Responses ◽

Plant Defence ◽

Plant Growth Promoting Rhizobacteria ◽

Molecular Data ◽

Flavonoid Metabolism ◽

Plant Growth Promoting ◽

Plant Genes ◽

Growth Promoting

This paper originates from an address at the 8th International Symposium on Nitrogen Fixation with Non-Legumes, Sydney, NSW, December 2000 Arabidopsis thaliana L. has many features favoring its use as a model in studies of plant-growth-promoting rhizobacteria (PGPR), such as diazotrophs. Several niches are colonized in the root system of Arabidopsis, including xylem, and intact colonized roots can be observed microscopically without sectioning of tissues. Studies of plant genes involved in colonization are facilitated by the ease with which plants are transformed and by the availability of mutant lines and other accessions obtainable from stock centers. Lines of Arabidopsis carrying reporter gene fusions are helping to reveal the pattern of expression of previously cloned plant genes induced by rhizobacteria. Studies utilizing indole-3-acetic acid (IAA)-producing PGPR and Arabidopsis that contain an auxin-responsive GUS fusion suggest that plants perceive IAA released by bacteria in the rhizosphere. The role of flavonoids in the colonization of non-legumes is being assessed using transgenic Arabidopsis with altered flavonoid metabolism and using tt mutants, which lack functional versions of specific genes for flavonoid metabolism. Studies of plant defence and of stress responses are producing molecular data on plant genes induced by inoculation of Arabidopsis roots with non-pathogens.

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A Siderophore Analog of Fimsbactin from Acinetobacter Hinders Growth of the Phytopathogen Pseudomonas syringae and Induces Systemic Priming of Immunity in Arabidopsis thaliana

Pathogens ◽

10.3390/pathogens9100806 ◽

2020 ◽

Vol 9 (10) ◽

pp. 806

Author(s):

Fabrice Betoudji ◽

Taha Abd El Rahman ◽

Marvin J. Miller ◽

Manuka Ghosh ◽

Mario Jacques ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Antibacterial Activity ◽

Pseudomonas Syringae ◽

Quantitative Polymerase Chain Reaction ◽

Plant Growth Promoting Rhizobacteria ◽

Infection Model ◽

Plant Infection ◽

Plant Growth Promoting ◽

Acinetobacter Spp

Siderophores produced in soil by plant growth-promoting rhizobacteria (PGPRs) play several roles, including nutrient mobilizers and can be useful as plants defense elicitors. We investigated the role of a synthetic mixed ligand bis-catechol-mono-hydroxamate siderophore (SID) that mimics the chemical structure of a natural siderophore, fimsbactin, produced by Acinetobacter spp. in the resistance against the phytopathogen Pseudomonas syringaepv tomato DC3000 (Pst DC3000), in Arabidopsis thaliana. We first tested the antibacterial activity of SID against Pst DC3000 in vitro. After confirming that SID had antibacterial activity against Pst DC3000, we tested whether the observed in vitro activity could translate into resistance of Arabidopsis to Pst DC3000, using bacterial loads as endpoints in a plant infection model. Furthermore, using quantitative polymerase chain reaction, we explored the molecular actors involved in the resistance of Arabidopsis induced by SID. Finally, to assure that SID would not interfere with PGPRs, we tested in vitro the influence of SID on the growth of a reference PGPR, Bacillus subtilis. We report here that SID is an antibacterial agent as well as an inducer of systemic priming of resistance in A. thaliana against Pst DC3000, and that SID can, at the same time, promote growth of a PGPR.

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