Identification and profiling of miRNAs during herbivory reveals jasmonate-dependent and -independent patterns of accumulation in Nicotiana attenuata

Background Plant microRNAs (miRNAs) play key roles in the transcriptional responses to environmental stresses. However, the role of miRNAs in responses to insect herbivory has not been thoroughly explored. To identify herbivory-responsive miRNAs, we identified conserved miRNAs in the ecological model plant Nicotiana attenuata whose interactions with herbivores have been well-characterized in both laboratory and field studies. Results We identified 59 miRNAs from 36 families, and two endogenous trans-acting small interfering RNAs (tasiRNA) targeted by miRNAs. We characterized the response of the precursor and mature miRNAs to simulated attack from the specialist herbivore Manduca sexta by quantitative PCR analysis and used ir-aoc RNAi transformants, deficient in jasmonate biosynthesis, to identify jasmonate-dependent and -independent miRNA regulation. Expression analysis revealed that groups of miRNAs and tasiRNAs were specifically regulated by either mechanical wounding or wounding plus oral secretions from M. sexta larvae, and these small RNAs were accumulated in jasmonate-dependent or -independent manners. Moreover, cDNA microarray analysis indicated that the expression patterns of the corresponding target genes were correlated with the accumulation of miRNAs and tasiRNAs. Conclusions We show that a group of miRNAs and tasiRNAs orchestrates the expression of target genes involved in N. attenuata’s responses to herbivore attack

Ultrasonic Influence on the Characteristics of the Interface of the SDS of CdTe/СTO Structures

The effect of ultrasonic treatment on the generation characteristics of the interface between the PDP of CdTe/STO structures obtained by magnetron ion sputtering has been studied

Chemical Interventions to Alleviate Salt Stress in Cotton Plants: A Review

The alleviation of salt stress in cotton plants through the application of exogenous chemicals has emerged as a viable strategy to mitigate the adverse effects on various plant attributes, including growth, development, yield, and flowering. Plant hormones, known for their efficacy at low doses, have garnered significant attention in this context. Despite being inherently susceptible to salt stress, cotton plants experience severe impediments in water absorption from the soil, leading to delayed growth and development. Several phytohormones, including jasmonic acid, salicylic acid, and glycine betaine, have been extensively investigated in numerous studies for their potential to ameliorate salt stress in cotton plants. Promising results have been obtained with both foliar and seed treatments employing these substances. This foundational knowledge has paved the way for the development of alternative strategies to mitigate salt stress. However, the practical utilization of these chemicals is hindered by their elevated cost. Plant growth regulators, such as nitric oxide and melatonin, have also garnered interest for their ability to alleviate salt stress in cotton plants. Numerous studies have corroborated their effectiveness in this regard. This review comprehensively examines the aforementioned substances and extracts that have been investigated for their potential to mitigate the detrimental effects of salt stress on cotton plants

Ligand-receptor co-evolution shaped the jasmonate pathway in land plants.

The phytohormone jasmonoyl-isoleucine (JA-Ile) regulates defense, growth and developmental responses in vascular plants. Bryophytes have conserved sequences for all JA-Ile signaling pathway components but lack JA-Ile. We show that, in spite of 450 million years of independent evolution, the JA-Ile receptor COI1 is functionally conserved between the bryophyte Marchantia polymorpha and the eudicot Arabidopsis thaliana but COI1 responds to different ligands in each species. We identified the ligand of Marchantia MpCOI1 as two isomeric forms of the JA-Ile precursor dinor-OPDA (dinor-cis-OPDA and dinor-iso-OPDA). We demonstrate that AtCOI1 functionally complements Mpcoi1 mutation and confers JA-Ile responsiveness and that a single-residue substitution in MpCOI1 is responsible for the evolutionary switch in ligand specificity. Our results identify the ancestral bioactive jasmonate and clarify its biosynthetic pathway, demonstrate the functional conservation of its signaling pathway, and show that JA-Ile and COI1 emergence in vascular plants required co-evolution of hormone biosynthetic complexity and receptor specificity

JA but not JA-Ile is the cell-nonautonomous signal activating JA mediated systemic defenses to herbivory in Nicotiana attenuata (FA)

The whole-plant activation of defense responses to wounding and herbivory requires systemic signaling in which jasmonates (JAs) play a pivotal role. To examine the nature of the slower cell-nonautonomous as compared to the rapid cell-autonomous signal in mediating systemic defenses in Nicotiana attenuata, reciprocal stem grafting-experiments were used with plants silenced for the JA biosynthetic gene ALLENE OXIDE CYCLASE (irAOC) or plants transformed to create JA sinks by ectopically expressing Arabidopsis JA-O-methyltransferase (ovJMT). JA-impaired irAOC plants were defective in the cell-nonautonomous signaling pathway but not in JA transport. Conversely, ovJMT plants abrogated the production of a graft-transmissible JA signal. Both genotypes displayed unaltered cell-autonomous signaling. Defense responses (17-hydroxygeranyllinalool diterpene glycosides, nicotine, and proteinase inhibitors) and metabolite profiles were differently induced in irAOC and ovJMT scions in response to graft-transmissible signals from elicited wild type stocks. The performance of Manduca sexta larvae on the scions of different graft combinations was consistent with the patterns of systemic defense metabolite elicitations. Taken together, we conclude that JA and possibly MeJA, but not JA-Ile, either directly functions as a long-distance transmissible signal or indirectly interacts with long distance signal(s) to activate systemic defense responses

Формула Карлемана для матричного полидиска

In this work an integral formula for a matrix polydisk is obtained. For a function from the Hardy class it allows to recover its value at any interior point from its values on a part of the Shilov boundaryВ работе получена интегральная формула для матричного полидиска. Для функций из класса Харди дано утверждение, позволяющее восстановить значения функции во внутренних точках полидиска по ее значениям на части границы Шилов

Identification and profiling of miRNAs during herbivory reveals jasmonate-dependent and -independent patterns of accumulation in <it>Nicotiana attenuata</it>

Abstract Background Plant microRNAs (miRNAs) play key roles in the transcriptional responses to environmental stresses. However, the role of miRNAs in responses to insect herbivory has not been thoroughly explored. To identify herbivory-responsive miRNAs, we identified conserved miRNAs in the ecological model plant Nicotiana attenuata whose interactions with herbivores have been well-characterized in both laboratory and field studies. Results We identified 59 miRNAs from 36 families, and two endogenous trans-acting small interfering RNAs (tasiRNA) targeted by miRNAs. We characterized the response of the precursor and mature miRNAs to simulated attack from the specialist herbivore Manduca sexta by quantitative PCR analysis and used ir-aoc RNAi transformants, deficient in jasmonate biosynthesis, to identify jasmonate-dependent and -independent miRNA regulation. Expression analysis revealed that groups of miRNAs and tasiRNAs were specifically regulated by either mechanical wounding or wounding plus oral secretions from M. sexta larvae, and these small RNAs were accumulated in jasmonate-dependent or -independent manners. Moreover, cDNA microarray analysis indicated that the expression patterns of the corresponding target genes were correlated with the accumulation of miRNAs and tasiRNAs. Conclusions We show that a group of miRNAs and tasiRNAs orchestrates the expression of target genes involved in N. attenuata’s responses to herbivore attack.</p