Wounding-Induced WRKY8 Is Involved in Basal Defense in Arabidopsis

The WRKY family of plant transcription factors controls several types of plant stress responses. Arabidopsis WRKY8, localized to the nucleus, is mainly induced by abscissic acid, H2O2, wounding, Pseudomonas syringae and Botrytis cinerea infection, and aphid and maggot feeding. To determine its biological functions, we isolated loss-of-function T-DNA insertion mutants and generated gain-of-function overexpressing WRKY8 transgenic plants in Arabidopsis. Plants expressing the mutated WRKY8 gene showed increased resistance to P. syringae but slightly decreased resistance to B. cinerea. In contrast, transgenic plants overexpressing WRKY8 were more susceptible to P. syringae infection but more resistant to B. cinerea infection. The contrasting responses to the two pathogens were correlated with opposite effects on pathogen-induced expression of two genes; salicylic acid-regulated PATHOGENESIS-RELATED1 (PR1) and jasmonic acid-regulated PDF1.2. Therefore, our results suggest that WRKY8 is a negative regulator of basal resistance to P. syringae and positive regulator to B. cinerea.

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The Interplay among Polyamines and Nitrogen in Plant Stress Responses

Plants ◽

10.3390/plants8090315 ◽

2019 ◽

Vol 8 (9) ◽

pp. 315 ◽

Cited By ~ 9

Author(s):

Konstantinos Paschalidis ◽

Georgios Tsaniklidis ◽

Bao-Quan Wang ◽

Costas Delis ◽

Emmanouil Trantas ◽

...

Keyword(s):

Transgenic Plants ◽

Stress Responses ◽

Plant Stress ◽

Abiotic And Biotic Stresses ◽

Biotic Stresses ◽

N Assimilation ◽

Major Player ◽

Key Factor ◽

Plant Stress Responses ◽

N Metabolism

The interplay between polyamines (PAs) and nitrogen (N) is emerging as a key factor in plant response to abiotic and biotic stresses. The PA/N interplay in plants connects N metabolism, carbon (C) fixation, and secondary metabolism pathways. Glutamate, a pivotal N-containing molecule, is responsible for the biosynthesis of proline (Pro), arginine (Arg) and ornithine (Orn) and constitutes a main common pathway for PAs and C/N assimilation/incorporation implicated in various stresses. PAs and their derivatives are important signaling molecules, as they act largely by protecting and preserving the function/structure of cells in response to stresses. Use of different research approaches, such as generation of transgenic plants with modified intracellular N and PA homeostasis, has helped to elucidate a plethora of PA roles, underpinning their function as a major player in plant stress responses. In this context, a range of transgenic plants over-or under-expressing N/PA metabolic genes has been developed in an effort to decipher their implication in stress signaling. The current review describes how N and PAs regulate plant growth and facilitate crop acclimatization to adverse environments in an attempt to further elucidate the N-PAs interplay against abiotic and biotic stresses, as well as the mechanisms controlling N-PA genes/enzymes and metabolites.

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Effect of Pyraclostrobin Application on Viral and Bacterial Diseases of Tomato

Plant Disease ◽

10.1094/pdis-10-15-1216-re ◽

2016 ◽

Vol 100 (7) ◽

pp. 1321-1330 ◽

Cited By ~ 7

Author(s):

Nicholas Skandalis ◽

Anastasia Dimopoulou ◽

Despoina Beri ◽

Aliki Tzima ◽

Ioanna Malandraki ◽

...

Keyword(s):

Pseudomonas Syringae ◽

Stress Responses ◽

Disease Incidence ◽

Plant Stress ◽

Defense Responses ◽

Bacterial Disease ◽

Bacterial Diseases ◽

Plant Stress Responses ◽

Promote Plant Growth ◽

Cmv Disease

Quinone outside inhibitors (QoI) are powerful fungicides, which have been reported, additionally to their fungicide activity, to increase plant capacity to activate cellular defense responses and to promote plant growth. In this work, the effect of the QoI class fungicide pyraclostrobin was examined against Cucumber mosaic virus (CMV), Potato virus Y (PVY) and Pseudomonas syringae pv. tomato in tomato plants following artificial inoculation of the plants with the pathogens. Under controlled environmental conditions, pyraclostrobin delayed viral and bacterial disease development, even if P. syringae pv. tomato internal population levels were not affected significantly. In contrast, under field conditions in commercial greenhouses, a reduced CMV disease incidence throughout the tomato cultivation period was recorded. Gene expression analysis indicated an effect of pyraclostrobin application on tomato MAPKs transcript levels and a possible interference with plant stress responses.

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Faculty Opinions recommendation of Mapping proteome-wide targets of protein kinases in plant stress responses.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.737278120.793570463 ◽

2020 ◽

Author(s):

Shuhua Yang

Keyword(s):

Protein Kinases ◽

Stress Responses ◽

Plant Stress ◽

Plant Stress Responses

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Versatile Physiological Functions of Plant GSK3-Like Kinases

Genes ◽

10.3390/genes12050697 ◽

2021 ◽

Vol 12 (5) ◽

pp. 697

Author(s):

Juan Mao ◽

Wenxin Li ◽

Jing Liu ◽

Jianming Li

Keyword(s):

Stress Responses ◽

Glycogen Synthase ◽

Plant Stress ◽

Normal Growth ◽

Growth Conditions ◽

Genetic Studies ◽

Physiological Functions ◽

Environmental Signals ◽

Plant Stress Responses ◽

Diverse Plant

The plant glycogen synthase kinase 3 (GSK3)-like kinases are highly conserved protein serine/threonine kinases that are grouped into four subfamilies. Similar to their mammalian homologs, these kinases are constitutively active under normal growth conditions but become inactivated in response to diverse developmental and environmental signals. Since their initial discoveries in the early 1990s, many biochemical and genetic studies were performed to investigate their physiological functions in various plant species. These studies have demonstrated that the plant GSK3-like kinases are multifunctional kinases involved not only in a wide variety of plant growth and developmental processes but also in diverse plant stress responses. Here we summarize our current understanding of the versatile physiological functions of the plant GSK3-like kinases along with their confirmed and potential substrates.

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OsNAC45 is Involved in ABA Response and Salt Tolerance in Rice

Rice ◽

10.1186/s12284-020-00440-1 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Xiang Zhang ◽

Yan Long ◽

Jingjing Huang ◽

Jixing Xia

Keyword(s):

Transcription Factors ◽

Salt Stress ◽

Salt Tolerance ◽

Stress Responses ◽

Crop Yields ◽

Plant Stress ◽

Root Cells ◽

Nac Transcription Factors ◽

Rice Plants ◽

Plant Stress Responses

Abstract Background Salt stress threatens crop yields all over the world. Many NAC transcription factors have been reported to be involved in different abiotic stress responses, but it remains unclear how loss of these transcription factors alters the transcriptomes of plants. Previous reports have demonstrated that overexpression of OsNAC45 enhances salt and drought tolerance in rice, and that OsNAC45 may regulate the expression of two specific genes, OsPM1 and OsLEA3–1. Results Here, we found that ABA repressed, and NaCl promoted, the expression of OsNAC45 in roots. Immunostaining showed that OsNAC45 was localized in all root cells and was mainly expressed in the stele. Loss of OsNAC45 decreased the sensitivity of rice plants to ABA and over-expressing this gene had the opposite effect, which demonstrated that OsNAC45 played an important role during ABA signal responses. Knockout of OsNAC45 also resulted in more ROS accumulation in roots and increased sensitivity of rice to salt stress. Transcriptome sequencing assay found that thousands of genes were differently expressed in OsNAC45-knockout plants. Most of the down-regulated genes participated in plant stress responses. Quantitative real time RT-PCR suggested that seven genes may be regulated by OsNAC45 including OsCYP89G1, OsDREB1F, OsEREBP2, OsERF104, OsPM1, OsSAMDC2, and OsSIK1. Conclusions These results indicate that OsNAC45 plays vital roles in ABA signal responses and salt tolerance in rice. Further characterization of this gene may help us understand ABA signal pathway and breed rice plants that are more tolerant to salt stress.

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