Abstract Membranes are primary sites of perception environmental stimuli. Polyunsaturated fatty acids major structural constituents membranes that also function as modulators a multitude signal transduction pathways evoked by Different stresses induce production distinct blend oxygenated polyunsaturated acids, “oxylipins.” We employed three Arabidopsis (Arabidopsis thaliana) ecotypes to examine the oxylipin signature in response specific and determined wounding drought differentially alter...

Abstract Fatty acid structure affects cellular activities through changes in membrane lipid composition and the generation of a diversity bioactive derivatives. Eicosapolyenoic acids are released into plants upon infection by oomycete pathogens, suggesting they may elicit plant defenses. We exploited transgenic Arabidopsis thaliana (designated EP) producing eicosadienoic, eicosatrienoic, arachidonic (AA), aimed at mimicking pathogen release these compounds. also examined their effect on...

Many inducible plant-defense responses are activated by jasmonates (JAs), C(6)-aldehydes, and their corresponding derivatives, produced the two main competing branches of oxylipin pathway, allene oxide synthase (AOS) hydroperoxide lyase (HPL) branches, respectively. In addition to competition for substrates, these branch-pathway-derived metabolites have substantial overlap in regulation gene expression. Past experiments define role C(6)-aldehydes plant defense were biased towards exogenous...

Calcium (Ca(2+)) is a key second messenger in eukaryotes and regulates diverse cellular processes, most notably via calmodulin (CaM). In Arabidopsis thaliana, IQD1 (IQ67 domain 1) the founding member of IQD family putative CaM targets. The 33 predicted proteins share conserved 67 amino acids that characterized by unique arrangement multiple recruitment motifs, including so-called IQ motifs. Whereas has been implicated regulation defense metabolism, biochemical functions remain to be...

Abstract Background Calcium signaling plays a prominent role in plants for coordinating wide range of developmental processes and responses to environmental cues. Stimulus-specific generation intracellular calcium transients, decoding signatures, transformation the signal into cellular are integral modules transduction process. Several hundred proteins with functions circuits have been identified, number downstream targets sensors is expected increase. We previously identified novel,...

Abstract Jasmonic acid and its derived metabolites (JAs) orchestrate plant defense against insects fungi. 12-Oxo-phytodienoic (OPDA), a JA precursor, has also been implicated in defense. We sought to define JAs OPDA functions through comparative susceptibility characteristics of three Arabidopsis (Arabidopsis thaliana) genotypes: aos, lacking OPDA; opda reductase3 (opr3), deficient production but can accumulate transgenics that overexpress OPR3. opr3, like is susceptible cabbage loopers...

Plants respond to warm temperature by increased elongation growth of organs enhance cooling capacity. Phytohormones, such as auxin and brassinosteroids, regulate this process. However, our view on the players involved in temperature-mediated remains fragmentary. Here, we show that leads an expression JOXs ST2A, genes controlling jasmonate catabolism. This elevated 12HSO4-JA level consequently a reduced bioactive jasmonates. Ultimately results more JAZ proteins, which facilitates plant under...

Abstract Compatibility between plants and obligate biotrophic fungi requires fungal mechanisms for efficiently obtaining nutrients counteracting plant defenses under conditions that are expected to induce changes in the host transcriptome. A key step proliferation of is haustorium differentiation. Here we analyzed global gene expression patterns Arabidopsis thaliana leaves during formation haustoria by Golovinomyces cichoracearum. At this time, endogenous levels salicylic acid (SA) jasmonic...

The Arabidopsis Ca(2+)/calmodulin (CaM)-binding transcription factor SIGNAL RESPONSIVE1 (AtSR1/CAMTA3) was previously identified as a key negative regulator of plant immune responses. Here, we report new role for AtSR1 critical component defense against insect herbivory. Loss function impairs tolerance to feeding by the generalist herbivore Trichoplusia ni well wound-induced jasmonate accumulation. susceptibility atsr1 mutant is associated with decreased total glucosinolate (GS) levels. two...

Insect herbivores have developed a myriad of strategies to manipulate the defense responses their host plants. Here we provide evidence that chewing insects differentially alter oxylipin profiles produced by two main and competing branches plant defensive response pathway, allene oxide synthase (AOS) hydroperoxide lyase (HPL) branches, which are responsible for wound-inducible production jasmonates (JAs), green leafy volatiles (GLVs) respectively. Specifically, used three Arabidopsis...

Protein molecular adaptation to drastically shifting salinities was studied in dCA II, an α-type carbonic anhydrase (EC 4.2.1.1) from the exceptionally salt-tolerant unicellular green alga Dunaliella salina . The salt-inducible, extracellular II is highly and thus differs its mesophilic homologs. crystal structure of determined at 1.86-Å resolution, globally similar other anhydrases except for two extended α-helices added Na-binding loop. Its unusual electrostatic properties include a...

Through evolution, plants have developed a myriad of strategies to adapt environmental perturbations. Using 3 Arabidopsis ecotypes in conjunction with various transgenic and mutant lines, we provide evidence that wounding drought differentially alter the metabolic signatures derived from 2 main competing oxylipin-pathway branches, namely JA its precursor 12-OPDA produced by Allene oxide synthase (AOS) branch, aldehydes corresponding alcohols generated Hydroperoxide lyase (HPL) branch....

Jasmonates are plant hormones that involved in the regulation of different aspects life, wherein their functions and molecular mechanisms action wheat still poorly studied. With aim gaining more insights into role jasmonic acid (JA) growth, development, responses to environmental stresses, we have generated transgenic bread plants overexpressing Arabidopsis 12-OXOPHYTODIENOATE REDUCTASE 3 (AtOPR3), one key genes JA biosynthesis pathway. Analysis showed AtOPR3 overexpression affects including...

The lipid-derived hormones jasmonates (JAs) play key functions in a wide range of physiological and developmental processes that regulate growth, secondary metabolism defense against biotic abiotic stresses. In this connection, biosynthesis, tissue-specific distribution, metabolism, perception, signaling JAs have been the target extensive studies. recent years, involvement pathway regulation growth adaptive responses to environmental challenges has further examined. However, JAs-mediated...

Environmental stresses induce production of oxylipins synthesized by the two main biosynthetic branches, allene oxide synthase (AOS) and hydroperoxide lyase (HPL). Here, we investigate how waterlogging-mediated alteration AOS- HPL-derived metabolic profile results in modulation central metabolism ultimately enhanced tolerance to this environmental stress Arabidopsis thaliana. Waterlogging leads increased levels metabolites, studies genotypes lacking either one or both branches further...

12-Oxophytodienoate reductase is the enzyme involved in biosynthesis of phytohormone jasmonates, which are considered to be major regulators plant tolerance biotic challenges, especially necrotrophic pathogens. However, we observe compromised fungal pathogen Botrytis cinerea transgenic hexaploid bread wheat and tetraploid emmer plants overexpressing 12-OXOPHYTODIENOATE REDUCTASE-3 gene from Arabidopsis thaliana, while themselves, endogenously produced exogenously applied jasmonates exert a...