Heterotrimeric G proteins-mediated resistance to necrotrophic pathogens includes mechanisms independent of salicylic acid-, jasmonic acid/ethylene- and abscisic acid-mediated defense signaling

Since receptor-coupled G proteins increase GTP hydrolysis (GTPase) activity upon ligands binding to the receptor, a study was undertaken to determine if abscisic acid (ABA) induced such an effect. Plasma membranes isolated from etiolated maize (Zea mays L.) coleoptiles were enriched in GTPase activity relative to microsomal fractions. Vanadate was included in the assay to inhibit the high levels of vanadate sensitive low affinity GTPases present. Under these conditions, GTPase activity was enhanced by Mg2+, stimulated by mastoparan, and inhibited by GTPγS indicating the presence of either monomeric or heterotrimeric G proteins. The combination of NaF and AlCl3 is expected to inhibit heterotrimeric G protein activity but had little effect on GTPase activity in maize coleoptile membranes. Cholera toxin enhanced basal GTPase activity, confirming the presence of heterotrimeric G proteins in maize plasma membranes. Pertussis toxin also slightly enhanced basal GTPase activity in maize membranes. Abscisic acid enhanced GTPase activity optimally at 5 mmol/L Mg2+ in a concentration dependent manner by 1.5-fold at 10 µmol/L and up to three-fold at 100 µmol/L ABA. Abscisic acid induced GTPase activity was inhibited by GTPγS, the combination of NaF and AlCl3, and pertussis toxin. Overall, these results are typical of a receptor-coupled G protein responding to its ligand.

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Global Trends in Phytohormone Research: Google Trends Analysis Revealed African Countries Have Higher Demand for Phytohormone Information

Plants ◽

10.3390/plants9091248 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1248

Author(s):

Tapan Kumar Mohanta ◽

Yugal Kishore Mohanta ◽

Dhananjay Yadav ◽

Abeer Hashem ◽

Elsayed Fathi Abd_Allah ◽

...

Keyword(s):

United States ◽

Salicylic Acid ◽

Abscisic Acid ◽

Jasmonic Acid ◽

United States Of America ◽

World Wide ◽

The United States ◽

Google Trends ◽

Search Terms ◽

The World

The lines of research conducted within a country often reflect its focus on current and future economic needs. Analyzing “search” trends on the internet can provide important insight into predicting the direction of a country in regards to agriculture, health, economy, and other areas. ‘Google Trends’ collects data on search terms from different countries, and this information can be used to better understand sentiments in different countries and regions. Agricultural output is responsible for feeding the world and there is a continuous quest to find ways to make agriculture more productive, safe, and reliable. The application of phytohormones has been used in agriculture world-wide for many years to improve crop production and continues to be an active area of research for the application in plants. Therefore, in the current study, we searched ‘Google Trends’ using the phytohormone search terms, abscisic acid, auxins, brassinosteroids, cytokinin, ethylene, gibberellins, jasmonic acid, salicylic acid, and strigolactones. The results indicated that the African country Zambia had the greatest number of queries on auxin research, and Kenya had the most queries in cytokinin and gibberellin research world-wide. For other phytohormones, India had the greatest number of queries for abscisic acid and South Korea had the greatest number of ethylene and jasmonic acid search world-wide. Queries on salicylic acid have been continuously increasing while the least number of queries were related to strigolactones. Only India and United States of America had significant numbers of queries on all nine phytohormones while queries on one or more phytohormones were absent in other countries. India is one of the top five crop-producing countries in the world for apples, millet, orange, potato, pulses, rice, sugarcane, tea, and wheat. Similarly, the United States of America is one of the top five crop-producing countries of the world for apples, grapes, maze, orange, potato, sorghum, sugarcane, and wheat. These might be the most possible factors for the search queries found for all the nine phytohormones in India and the United States of America.

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Transcriptome Analysis of Genes Involved in Aluminum Stress Responses in Peanut (Arachis Hypogaea L.)

10.21203/rs.3.rs-1057251/v1 ◽

2021 ◽

Author(s):

Gegen Bao ◽

Shengyu Li ◽

Qi Zhou ◽

Umair Ashraf ◽

Jingxuan Qiao ◽

...

Keyword(s):

Salicylic Acid ◽

Transcription Factors ◽

Abscisic Acid ◽

Jasmonic Acid ◽

Stress Tolerance ◽

Arachis Hypogaea ◽

Transcriptome Analysis ◽

Stress Responses ◽

Al Tolerance ◽

Al Stress

Abstract Background Aluminum (Al) contamination inhibits plant growth and development, however, mechanisms involved in Al stress tolerance in peanut (Arachis hypogaea L.) were rarely studied. The present study was comprised of four Al levels i.e., 0, 1.25, 2.5 and 5 mmol l−1 AlCl3.18H2O regarded as Al0, Al1, Al2, and Al3. The respective concentrations were added in Hoagland nutrient solution and replaced every three days. Result Results revealed that seeding length low Al concentration (Al1) treatment had no noticeable effect on seeding lenght, while higher Al concentration (Al2 and Al3) treatment significantly inhibited seeding lenght. The differentially expressed genes (DEGs) of plant hormone metabolism pathway were significantly enriched whereas the contents of salicylic acid (SA) and abscisic acid (ABA) were up-regulated, and jasmonic acid (JA) were down-regulated to different levels. Moreover, transcription factors (TFs) and ALMT9 and FRDL1 genes were up-regulated at higher Al concentration and down-regulated at the lowest Al concentration (Al1). Conclusions Overall, Higher Al concentrations up-regulated the expression of transcription factors (TFs), and ALMT9 and FRDL1 genes to resist the stress of high Al concentrations whereas transcriptome analysis revealed that Al stress tolerance is closely related to endogenous hormone contents i.e., salicylic acid (SA), abscisic acid (ABA), and jasmonic acid (JA). This study preliminarily analyzed the molecular mechanism of Al tolerance in peanut and provided a theoretical rationale for developing new Al-tolerant peanut cultivars.

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Water Stress Responses of Tomato Mutants Impaired in Hormone Biosynthesis Reveal Abscisic Acid, Jasmonic Acid and Salicylic Acid Interactions

Frontiers in Plant Science ◽

10.3389/fpls.2015.00997 ◽

2015 ◽

Vol 6 ◽

Cited By ~ 39

Author(s):

Valeria A. Muñoz-Espinoza ◽

María F. López-Climent ◽

José A. Casaretto ◽

Aurelio Gómez-Cadenas

Keyword(s):

Salicylic Acid ◽

Abscisic Acid ◽

Water Stress ◽

Jasmonic Acid ◽

Stress Responses ◽

Hormone Biosynthesis

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Auxin Metabolism Is Involved in Fruit Set and Early Fruit Development in the Parthenocarpic Tomato “R35-P”

Frontiers in Plant Science ◽

10.3389/fpls.2021.671713 ◽

2021 ◽

Vol 12 ◽

Author(s):

Shaoli Zhang ◽

Xin Gu ◽

Jingcheng Shao ◽

Zhifeng Hu ◽

Wencai Yang ◽

...

Keyword(s):

Salicylic Acid ◽

Abscisic Acid ◽

Jasmonic Acid ◽

Acid Content ◽

High Performance ◽

Fruit Set ◽

Early Spring ◽

Tomato Production ◽

Tomato Line ◽

Self Pollination

Parthenocarpic tomato can set fruit and develop without pollination and exogenous hormone treatments under unfavorable environmental conditions, which is beneficial to tomato production from late fall to early spring in greenhouses. In this study, the endogenous hormones in the ovaries of the parthenocarpic tomato line “R35-P” (stigma removed or self-pollination) and the non-parthenocarpic tomato line “R35-N” (self-pollination) at four stages between preanthesis and postanthesis investigated, using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). A nearly twofold IAA (indoleacetic acid) content was found in “R35-P” rather than in “R35-N” at −2 and 0 days after anthesis (DAA). Except at −2 DAA, a lower ABA (abscisic acid) content was observed in Pe (stigma removed in “R35-P”) compared to that in Ps (self-pollination in “R35-P”) or CK (self-pollination in “R35-N”). After pollination, although the content of GA1 (gibberellins acid 1) in CK increased, the levels of GAs (gibberellins acids) were notably low. At all four stages, a lower SA (salicylic acid) content was found in Ps and CK than in Pe, while the content and the change trend were similar in Ps and CK. The variation tendencies of JA (jasmonic acid) varied among Pe, Ps, and CK at the studied periods. Furthermore, KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analyses of transcriptomic data identified 175 differentially expressed genes (DEGs) related to plant hormone signal transduction, including 63 auxin-related genes, 27 abscisic acid-related genes, 22 ethylene-related genes, 16 cytokinin-related genes, 16 salicylic acid-related genes, 14 brassinosteroid-related genes, 13 jasmonic acid-related genes, and 4 gibberellin-related genes at −2 DAA and 0 DAA. Our results suggest that the fate of a fruit set or degeneration occurred before anthesis in tomato. Auxins, whose levels were independent of pollination and fertilization, play prominent roles in controlling a fruit set in “R35-P,” and other hormones are integrated in a synergistic or antagonistic way.

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Current understanding of the interplays between host hormones and plant viral infections

PLoS Pathogens ◽

10.1371/journal.ppat.1009242 ◽

2021 ◽

Vol 17 (2) ◽

pp. e1009242

Author(s):

Shanshan Zhao ◽

Yi Li

Keyword(s):

Salicylic Acid ◽

Abscisic Acid ◽

Gibberellic Acid ◽

Jasmonic Acid ◽

Plant Virus ◽

Viral Infections ◽

Abiotic Factors ◽

Current Understanding ◽

Hormone Signaling ◽

Virus Interactions

Phytohormones mediate plant development and responses to stresses caused by biotic agents or abiotic factors. The functions of phytohormones in responses to viral infection have been intensively studied, and the emerging picture of complex mechanisms provides insights into the roles that phytohormones play in defense regulation as a whole. These hormone signaling pathways are not simple linear or isolated cascades, but exhibit crosstalk with each other. Here, we summarized the current understanding of recent advances for the classical defense hormones salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) and also the roles of abscisic acid (ABA), auxin, gibberellic acid (GA), cytokinins (CKs), and brassinosteroids (BRs) in modulating plant–virus interactions.

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Transcriptome-based discovery of genes and networks related to RSC3Q-mediated resistance to Soybean mosaic virus in soybean

Crop and Pasture Science ◽

10.1071/cp20253 ◽

2020 ◽

Vol 71 (12) ◽

pp. 987

Author(s):

Yuan Yuan ◽

Yongqing Yang ◽

Jinlong Yin ◽

Yingchao Shen ◽

Bowen Li ◽

...

Keyword(s):

Salicylic Acid ◽

Abscisic Acid ◽

Jasmonic Acid ◽

Mosaic Virus ◽

Seed Quality ◽

Early Stage ◽

Soybean Mosaic Virus ◽

Pathway Enrichment Analysis ◽

Post Inoculation ◽

Resistance Response

Abstract Soybean mosaic virus (SMV) is a worldwide disease of soybean (Glycine max (L.) Merr.) that can cause serious reduction in yield and seed quality. Soybean cv. Qihuang-1 is an important source of resistance to SMV in China, carrying a resistance gene (RSC3Q) against SMV strain SC3. In order to discover genes and networks regulated by RSC3Q-mediated resistance in Qihuang-1, we analysed transcriptome data of a pair of near-isogenic lines, R (RSC3Q) and S (rSC3Q), from the cross Qihuang-1 × Nannong 1138-2 (rSC3Q), after SC3 inoculation. Many differentially expressed genes (DEGs) were identified in the R and S lines at 6, 20 and 48 h post-inoculation. Based on pathway-enrichment analysis of DEGs, three genes encoding calmodulin-like protein (Glyma03g28650, Glyma19g31395 and Glyma11g33790) with downregulated expression in the S line were identified in the plant–pathogen interaction pathway at 6 h post-inoculation. Analyses by quantitative real-time PCR were performed to verify that these three genes were not beneficial for SMV infection. Our results also revealed a complex plant-hormone signal network in RSC3Q-mediated resistance during the early stage of SMV infection. Expression of jasmonic acid repressor genes (TIFY/JAZ) and abscisic acid-induced genes (PP2C3a) was upregulated in the R line but not the S line. More DEGs related to indole-3-acetic acid were found in the R line than the S line, and no salicylic acid-related DEGs were identified. These results suggest that suppression of jasmonic acid or promotion of abscisic acid is important for RSC3Q-mediated resistance against SC3, and that salicylic acid may not act as a main regulator of RSC3Q-mediated resistance during early stages of SC3 infection. Growth and development were greatly affected through RSC3Q-mediated resistance responses after SC3 infection. Our understanding would be enhanced by identification of factors associated with RSC3Q that help to trigger the resistance response.

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Differential Tissue-Specific Jasmonic Acid, Salicylic Acid, and Abscisic Acid Dynamics in Sweet Cherry Development and Their Implications in Fruit-Microbe Interactions

Frontiers in Plant Science ◽

10.3389/fpls.2021.640601 ◽

2021 ◽

Vol 12 ◽

Cited By ~ 1

Author(s):

David H. Fresno ◽

Sergi Munné-Bosch

Keyword(s):

Salicylic Acid ◽

Abscisic Acid ◽

Jasmonic Acid ◽

Fruit Development ◽

Sweet Cherry ◽

Economic Losses ◽

Tissue Specific ◽

Sweet Cherries ◽

Fruit Decay ◽

Microbe Interactions

Sweet cherry is an important non-climacteric fruit with a high commercial interest, but exploitation of sweet cherry trees (Prunus avium L.) in orchards is usually subject to important economic losses due to fruit decay by pathogenic fungi and other microorganisms. Sweet cherries development and ripening are characterized by profound physiological changes in the fruit, among which the phytohormone abscisic acid (ABA) plays a pivotal role. In addition, sweet cherries are usually affected by fruit decay pathogens, and the role of other stress-related hormones such as jasmonic acid (JA) and salicylic acid (SA) may also be of paramount importance, not only from a developmental point of view, but also from a fruit-microbe interaction perspective. Here, a tissue-specific hormone quantification by LC-MS/MS, including the contents of JA, SA, and ABA, in the fruit exocarp and mesocarp of sweet cherries during fruit development from trees growing in a commercial orchard was carried out. Additionally, this study was complemented with the characterization of the culturable epiphytic and endophytic microbial communities of sweet cherries at various stages of fruit development and during cracking lesion formation. Our results revealed a completely differential behavior of phytohormones between both tissues (the exocarp and mesocarp), with a more dynamic exocarp in front of a more stable mesocarp, and with marked variations during fruit development. Microbial epiphytic community was mainly composed by yeasts, although rot-causing fungi like Alternaria spp. were always also present throughout fruit development. Endophytic colonization was poor, but it increased throughout fruit development. Furthermore, when the exocarp was naturally disrupted in sweet cherries suffering from cracking, the colonization by Alternaria spp. markedly increased. Altogether, results suggest that the fruit exocarp and mesocarp are very dynamic tissues in which endogenous phytohormones not only modulate fruit development and ripening but also fruit-microbe interactions.

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