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Lipid-transfer proteins (LTPs) are lipid-binding small proteins, ubiquitously distributed amongst plant kingdom. Apart from their involvement in plant defense, it has also been discovered that they induce allergic reactions in humans. A plethora of LTPs have been identified in vegetables, fruits, pollens, nuts, and latex, among which Pru p 3, a LTP allergen from peach fruit, is extensively studied and exhibits cross-reactivity with potential allergens from different species. In Cicer arietinum, a family of LTPs (CaLTPs) has been identified and their importance in plant defense during Helicoverpa armigera-infestation has been recognized. However, the determination of the allergenicity potential of CaLTPs has not been attempted. In this study, we aim to decipher the allergenicity potential of defense-related CaLTPs. The allergenicity potential prediction, and identification of B-cell epitope binding regions showed that the CaLTPs had conserved domains and B-cell epitopes in the same regions as Prup3 (a marker allergen for LTPs). Using molecular docking and simulations, we observed that the CaLTPs successfully interacted with the Immunoglobin E(IgE)with docking energies ranging from −315.5 to −268.4 and the structures were stabilized within 10 ns of simulation. Through this study, we intend to embellish our present knowledge and understanding of the sensitization and allergenicity potential of CaLTPs. Communicated by Ramaswamy H. Sarma

Drought is the most prevalent environmental stress that affects plants’ growth, development, and crop productivity. However, plants have evolved adaptive mechanisms to respond to the harmful effects of drought. They reprogram their: transcriptome, proteome, and metabolome that alter their cellular and physiological processes and establish cellular homeostasis. One of the crucial regulatory processes that govern this reprogramming is post-transcriptional regulation by microRNAs (miRNAs). miRNAs are small non-coding RNAs, involved in the downregulation of the target mRNA via translation inhibition/mRNA degradation/miRNA-mediated mRNA decay/ribosome drop off/DNA methylation. Many drought-inducible miRNAs have been identified and characterized in plants. Their main targets are regulatory genes that influence growth, development, osmotic stress tolerance, antioxidant defense, phytohormone-mediated signaling, and delayed senescence during drought stress. Overexpression of drought-responsive miRNAs (Osa-miR535, miR160, miR408, Osa-miR393, Osa-miR319, and Gma-miR394) in certain plants has led to tolerance against drought stress indicating their vital role in stress mitigation. Similarly, knock down (miR166/miR398c) or deletion (miR169 and miR827) of miRNAs has also resulted in tolerance to drought stress. Likewise, engineered Arabidopsis plants with miR165, miR166 using short tandem target mimic strategy, exhibited drought tolerance. Since miRNAs regulate the expression of an array of drought-responsive genes, they can act as prospective targets for genetic manipulations to enhance drought tolerance in crops and achieve sustainable agriculture. Further investigations toward functional characterization of diverse miRNAs, and understanding stress-responses regulated by these miRNAs and their utilization in biotechnological applications is highly recommended.

Apoptosis, a major hallmark of cancer cells, regulates cellular fate and homeostasis. BCL-2 (B-cell CLL/Lymphoma 2) protein family is popularly known to mediate the intrinsic mode of apoptosis, of which MCL-1 is a crucial member. Myeloid cell leukemia 1 (MCL-1) is an anti-apoptotic oncoprotein and one of the most investigated members of the BCL-2 family. It is commonly known to be genetically altered, aberrantly overexpressed, and primarily associated with drug resistance in various human cancers. Recent advancements in the development of selective MCL-1 inhibitors and evaluating their effectiveness in cancer treatment establish its popularity as a molecular target. The overall aim is the selective induction of apoptosis in cancer cells by using a single or combination of BCL-2 family inhibitors. Delineating the precise molecular mechanisms associated with MCL-1-mediated cancer progression will certainly improve the efficacy of clinical interventions aimed at MCL-1 and hence patient survival. This review is structured to highlight the structural characteristics of MCL-1, its specific interactions with NOXA, MCL-1-regulatory microRNAs, and at the same time focus on the emerging therapeutic strategies targeting our protein of interest (MCL-1), alone or in combination with other treatments.

A modified one-pot two-step method has been developed to synthesize N-(o-benzyloxyphenyl) benzohydroxamic acids from o-benzyloxy nitrobenzene in good to excellent yields. The synthesized N-(o-benzy...

Nanoparticles (NPs) possess specific physical and chemical features and they are capable enough to cross cellular barriers and show their effect on living organisms. Their capability to cross cellular barriers have been noticed for their application not only in medicine, electronics, chemical and physical sciences, but also in agriculture. In agriculture, nanotechnology can help to improve the growth and crop productivity by the use of various nanoscale products such as nanofertilizers, nanoherbicides, nanofungicides, nanopesticides etc. An optimized concentration of NPs can be administered by incubation of seeds, roots, pollen, isolated cells and protoplast, foliar spraying, irrigation with NPs, direct injection, hydroponic treatment and delivery by biolistics. Once NPs come in contact with plant cells, they are uptaken by plasmodesmatal or endocytosed pathways and translocated via apoplastic and / symplastic routes. Once beneficial NPs reach different parts of plants, they boost photosynthetic rate, biomass measure, chlorophyll content, sugar level, buildup of osmolytes and antioxidants. NPs also improve nitrogen metabolism, enhance chlorophyll as well as protein content and upregulate the expression of abiotic- and biotic stress-related genes. Herein, we review the state of art of different modes of application, uptake, transport and prospective beneficial role of NPs in stress management and crop improvement.

Cytochrome P450s (CYPs) are a versatile group of enzymes and one of the largest families of proteins, controlling various physiological processes via biosynthetic and detoxification pathways. CYPs perform multiple roles through a critical irreversible enzymatic reaction in which an oxygen atom is inserted within hydrophobic molecules, converting them into the reactive and hydro soluble components. During evolution, plants have acquired significantly more number of CYPs and represent about 1% of the encoded genes . CYPs are highly conserved proteins involved in growth, development and tolerance against biotic and abiotic stresses. Furthermore, CYPs reinforce plants' molecular and chemical defense mechanisms by regulating the biosynthesis of secondary metabolites, enhancing reactive oxygen species (ROS) scavenging and controlling biosynthesis and homeostasis of phytohormones, including abscisic acid (ABA) and jasmonates. Thus, they are the critical targets of metabolic engineering for enhancing plant defense against environmental stresses. Additionally, CYPs are also used as biocatalysts in the fields of pharmacology and phytoremediation. Herein, we highlight the role of CYPs in plant stress tolerance and their applications for human welfare.

Plasmepsin V (Plm V) is an essential aspartic protease required for survival of the malaria parasite, Plasmodium falciparum (Pf). Plm V is required for cleaving the PEXEL motifs of many Pf proteins...

Plants protect themselves against pest attack utilizing both direct and indirect modes of defense. The direct mode of defense includes morphological, biochemical, and molecular barriers that affect feeding, growth, and survival of herbivores whereas the indirect mode of defense includes release of a blend of volatiles that attract natural enemies of the pests. Both of these strategies adopted by plants are reinforced if the plants are supplied with one of the most abundant metalloids, silicon (Si). Plants absorb Si as silicic acid (Si(OH)4) and accumulate it as phytoliths, which strengthens their physical defense. This deposition of Si in plant tissue is up-regulated upon pest attack. Further, Si deposited in the apoplast, suppresses pest effector molecules. Additionally, Si up-regulates the expression of defense-related genes and proteins and their activity and enhances the accumulation of secondary metabolites, boosting induced molecular and biochemical defenses. Moreover, Si plays a crucial role in phytohormone-mediated direct and indirect defense mechanisms. It is also involved in the reduction of harmful effects of oxidative stress resulting from herbivory by accelerating the scavenging process. Despite increasing evidence of its multiple roles in defense against pests, the practical implications of Si for crop protection have received less attention. Here, we highlight recent developments in Si-mediated improved plant resistance against pests and its significance for future use in crop improvement.

With the advent of human civilization and anthropogenic activities in the shade of urbanization and global climate change, plants are exposed to a complex set of abiotic stresses. These stresses affect plants’ growth, development, and yield and cause enormous crop losses worldwide. In this alarming scenario of global climate conditions, plants respond to such stresses through a highly balanced and finely tuned interaction between signaling molecules. The abiotic stresses initiate the quick release of reactive oxygen species (ROS) as toxic by-products of altered aerobic metabolism during different stress conditions at the cellular level. ROS includes both free oxygen radicals {superoxide (O2•−) and hydroxyl (OH−)} as well as non-radicals [hydrogen peroxide (H2O2) and singlet oxygen (1O2)]. ROS can be generated and scavenged in different cell organelles and cytoplasm depending on the type of stimulus. At high concentrations, ROS cause lipid peroxidation, DNA damage, protein oxidation, and necrosis, but at low to moderate concentrations, they play a crucial role as secondary messengers in intracellular signaling cascades. Because of their concentration-dependent dual role, a huge number of molecules tightly control the level of ROS in cells. The plants have evolved antioxidants and scavenging machinery equipped with different enzymes to maintain the equilibrium between the production and detoxification of ROS generated during stress. In this present article, we have focused on current insights on generation and scavenging of ROS during abiotic stresses. Moreover, the article will act as a knowledge base for new and pivotal studies on ROS generation and scavenging.

Dhurrin, a cyanogenic glucoside, is a plant defensive chemical synthesized from aliphatic amino acids and consists of β-d-glucopyranose linked to α-hydroxy nitrile. It is catabolized by the consecutive action of hydroxynitrilase and β-glucosidase to release hydrogen cyanide on tissue disruption during herbivory. These phytoanticipins are widely distributed across various monocot and dicot plants such as Sorghum, Macadamia, Ostrya sp., and many other plant species with ornamental, pharmaceutical, medicinal, and food value. Although repellent properties of dhurrin against herbivores are often reported, less is known about its distribution, metabolism, mode of action against insects, and application for pest control. Herein, we highlight recent updates on dhurrin distribution, biosynthesis, and catabolism along with the cyanide detoxification pathway. Additionally, this article focuses on biological activities of dhurrin against various herbivores and opportunities to explore the utilization of dhurrin as a natural pest control agent and a substitute for chemically synthesized pesticides.

Single amino-acid substitution in a protein affects its structure and function. These changes are the primary reasons for the advent of many complex diseases. Analyzing single point mutations in a protein is crucial to see their impact and to understand the disease mechanism. This has given many biophysical resources, including databases and web-based tools to explore the effects of mutations on the structure and function of human proteins. For a given mutation, each tool provides a score-based outcomes which indicate deleterious probability. In recent years, developments in existing programs and the introduction of new prediction algorithms have transformed the state-of-the-art protein mutation analysis. In this study, we have performed a systematic study of the most commonly used mutational analysis programs (10 sequence-based and 5 structure-based) to compare their prediction efficiency. We have carried out extensive mutational analyses using these tools for previously known pathogenic single point mutations of five different proteins. These analyses suggested that sequence-based tools, PolyPhen2, PROVEAN, and PMut, and structure-based web tool, mCSM have a better prediction accuracy. This study indicates that the employment of more than one program based on different approaches should significantly improve the prediction power of the available methods.

Plant diseases pose a substantial threat to food availability, accessibility, and security as they account for economic losses of nearly $300 billion on a global scale. Although various strategies exist to reduce the impact of diseases, they can introduce harmful chemicals to the food chain and have an impact on the environment. Therefore, it is necessary to understand and exploit the plants’ immune systems to control the spread of pathogens and enable sustainable agriculture. Recently, growing pieces of evidence suggest a functional myriad of lipids to be involved in providing structural integrity, intracellular and extracellular signal transduction mediators to substantial cross-kingdom cell signaling at the host–pathogen interface. Furthermore, some pathogens recognize or exchange plant lipid-derived signals to identify an appropriate host or development, whereas others activate defense-related gene expression. Typically, the membrane serves as a reservoir of lipids. The set of lipids involved in plant–pathogen interaction includes fatty acids, oxylipins, phospholipids, glycolipids, glycerolipids, sphingolipids, and sterols. Overall, lipid signals influence plant–pathogen interactions at various levels ranging from the communication of virulence factors to the activation and implementation of host plant immune defenses. The current review aims to summarize the progress made in recent years regarding the involvement of lipids in plant–pathogen interaction and their crucial role in signal transduction.

Aldo-keto reductase 1C1 (AKR1C1) is a hydroxysteroid dehydrogenase, known to inactivate the biologically active progesterone into its corresponding 20 α-hydroxyprogesterone. Increased expression of the AKR1C1 gene in oncogenesis is linked with resistance to various anticancer agents and hence it is considered as an emerging drug target for the design and developing the novel anticancer drugs. We have performed QSAR pharmacophore modeling for AKR1C1 inhibitors followed by a virtual screening of ~ 59,000 compounds present at the Maybridge database. The screened compounds were refined using drug-like filters of Lipinski rule, ADMET plot, molecular docking and scoring and subsequently top 20 hits were selected. Selected compounds were subjected to the in vitro for AKR1C1 inhibition assay and best seven compounds bearing excellent binding affinity to the AKR1C1 were finally selected. The identified compounds may be exploited in hit-to-lead development and may also prove as an interventional strategy in preventing a pre-term birth due to declining levels of progesterone.

Zea mays defense response is well-crafted according to the physical and chemical weapons utilized by their invaders during the coevolutionary period. Maize plants employ diversified defense strategies and alter the spatiotemporal distribution of several classes of defensive compounds to affect insect herbivore performance. However, only little knowledge is available about the defense orchestration of maize in response to Spodoptera litura, a voracious Noctuidae pest. In order to decipher the defense status of Zea mays (African tall variety) against S. litura, a comparative feeding bioassay was executed, which revealed reduced performance of the herbivore on maize. In order to understand the molecular mechanism behind maize tolerance against S. litura, a microarray-based genome-wide expression analysis was performed. The comparative analysis displayed 792 differentially expressed genes (DEGs), wherein 357 genes were upregulated and 435 genes were downregulated at fold change ≥ 2 and p value ≤ 0.05. The upregulated genes were identified and categorized as defense-related, oxidative stress-related, transcription regulatory genes, protein synthesis genes, phytohormone-related, and primary and secondary metabolism-related. In contrast, downregulated genes were mainly associated with plant growth and development, indicating a balance of growth and defense response and utilization of a highly evolved C-diversion response were noticed. Maize plants showed better tolerance against herbivory and maintained its fitness using a combinatorial strategy. This peculiar response of Zea mays against S. litura offers an excellent possibility of managing polyphagous pests by spicing up the plant’s defensive response with tolerance mechanism.

The study of insect-plant interaction is a complex and dynamic process that employs multidimensional and multidisciplinary approaches. A comprehensive understanding of plant defense mechanisms against insect plunderer is fundamental, to build up a profitable and effective pest management strategy. In the last few decades, the technological evolution of various high-throughput omics technologies (i.e., genomics, transcriptomics, proteomics, metabolomics) enabled a qualitative as well as the quantitative record of several biological molecules. Transcriptomics involves genome-wide analysis studies that delineate gene expression pattern of cells and tissues. The extensive use of transcriptomics in the field of agriculture offers an excellent route of genomic research beyond traditional “model” organisms. It easily provides accessible and affordable data for almost any organism, both model and non-model plants, which can be exploited in developing pest-resistant crops. This chapter aims to summarize contemporary research conducted using transcriptomics techniques to decipher the mystery of insect-plant interaction along with a brief analysis of its limitations, technological expansion, and prospects of omics in solving the enigma of plant-insect interaction.

During the course of growth and development, plants encounter many biotic stressors (pathogens and herbivores), which affect crop productivity to a larger extent. Biotic stresses lead to various physiological, biochemical, molecular, and metabolic alterations in plants. One of the crucial changes, that is observed in response to pest and pathogen attack, is the generation of reactive oxygen species (ROS). The primary sites of ROS generation are chloroplast, mitochondria, and peroxisomes, but during stress, ROS are also generated at secondary sites, which include endoplasmic reticulum, cell wall, cell membrane, and apoplast. ROS includes free radicals (O2•−, OH•) as well as nonradicals (H2O2, 1O2). A high concentration of ROS leads to oxidative stress and causes lipid peroxidation, chlorophyll damage, redox imbalance, and nucleic acid and protein degradation. Therefore in order to reduce the deleterious effects of ROS, plants have developed antioxidant mechanisms. However, a low/moderate level of ROS also act as a signaling molecule and interact with other signaling compounds and activate plant defense/tolerance mechanisms.

The role of zinc oxide nanoparticles (ZnO NPs) in plants and agriculture attracted huge interests during the last few years. A whole range of positive of NPs has been demonstrated and these exquisite material can be serve as alternatives to many fertilizers, micronutrients, fungicides or antimicrobial chemicals. The ameliorative roles against abiotic stress (drought, salinity and high temperature) in various crops are particularly significant. However, high concentrations of ZnO NPs have been observed to produce a range of toxicity including growth/yield inhibition, physiological aberrations, cytotoxicity, genotoxicity and oxidative stress. The positive or negative effects depend on the type, dose of nanomaterials, methods of treatments, developmental stage, and genotype of the species or environmental conditions. Until a fuller understating of various modes of interactions between ZnO NPs and plant genome or epigenome develops, it is difficult to use these new resources for the optimal benefit, substituting conventional agents of growth promotion or protection. This requires development of appropriate methods to identify plant conditions and optimize the nanomaterial treatment.

The sudden emergence of severe respiratory disease, caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently become a public health emergency. Genome sequence analysis of SARS-CoV-2 revealed its close resemblance to the earlier reported SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). However, initial testing of the drugs used against SARS-CoV and MERS-CoV has been ineffective in controlling SARS-CoV-2. The present study highlights the genomic, proteomic, pathogenesis, and therapeutic strategies in SARS-CoV-2 infection. We have carried out sequence analysis of potential drug target proteins in SARS-CoV-2 and, compared them with SARS-CoV and MERS viruses. Analysis of mutations in the coding and non-coding regions, genetic diversity, and pathogenicity of SARS-CoV-2 has also been done. A detailed structural analysis of drug target proteins has been performed to gain insights into the mechanism of pathogenesis, structure-function relationships, and the development of structure-guided therapeutic approaches. The cytokine profiling and inflammatory signalling are different in the case of SARS-CoV-2 infection. We also highlighted possible therapies and their mechanism of action followed by clinical manifestation. Our analysis suggests a minimal variation in the genome sequence of SARS-CoV-2, may be responsible for a drastic change in the structures of target proteins, which makes available drugs ineffective., Graphical abstract Schematic representation of novel corona virus showing target proteins and its mechanism of host entry.Unlabelled Image, Highlights • The recent exposure to SARS-CoV-2 has affected entire world, resulted >0.4 million deaths. • Potential drug targets of SARS-CoV-2 are highly conserved. • A slight structural difference makes available drugs ineffective against SARS-CoV-2. • Cytokine storm during SARS-CoV-2 infection may be targeted to handle COVID-19 patients. • Many FDA approved drugs are showing positive effects in clinical trials but further validation in large subject groups is required.

Coronavirus diseases (COVID-19) is caused by a novel severe acute respiratory syndrome coronavirus (SARS-CoV-2), which is a positive single-stranded RNA virus having a large genome ~30 kb. SARS-CoV-2 is zoonotic and highly contagious, causing severe pneumonia-like symptoms. The efficacy of the different potential drug and drug candidates against COVID-19 has been investigated which are under various stages of clinical trials. The drugs effective against SARS, and Middle east respiratory syndrome (MERS), have been proposed to have a high potential for the treatment of COVID-19. Here, we selected plant-based materials implicated in the prevention and therapy of COVID-19. The vaccine has shown impressive results in producing antibodies against SARS-CoV2 and has been evaluated for safety, tolerance, and preliminary immunogenicity. Similarly, DNA/RNA-based therapy shown high clinical significance. The plant produces secondary metabolites in response to viral infection to protect them. Many nanomaterials produced by carbohydrates and lipids been exploited for their in-vitro and in-vivo delivery of antiviral therapeutics. Different classes of secondary metabolites have a different mechanism to counter virus attacks. While some natural medicines in the form of vitamins, minerals, herbs, and other nutrients help to enhance immunity, such measures should not replace social distancing, quarantining special care to protect from COVID-19. The standards of reporting were in accordance with the PRISMA guidelines.

Highlights • Insights into different diagnostic techniques of SARS-CoV-2 infection have been provided. • We highlighted the importance of different diagnosis methods of COVID-19. • Emerging drugs used in the treatment of COVID-19 are also discussed., The most important aspect of controlling COVID-19 is its timely diagnosis. Molecular diagnostic tests target the detection of any of the following markers such as the specific region of the viral genome, certain enzyme, RNA-dependent RNA polymerase, the structural proteins such as surface spike glycoprotein, nucleocapsid protein, envelope protein, or membrane protein of SARS-CoV-2. This review highlights the underlying mechanisms, advancements, and clinical limitations for each of the diagnostic techniques authorized by the Food and Drug Administration (USA). Significance of diagnosis triaging, information on specimen collection, safety considerations while handling, transport, and storage of samples have been highlighted to make medical and research community more informed so that better clinical strategies are developed. We have discussed here the clinical manifestations and hospital outcomes along with the underlying mechanisms for several drugs administered to COVID-19 prophylaxis. In addition to favourable clinical outcomes, the challenges, and the future directions of management of COVOD-19 are highlighted. Having a comprehensive knowledge of the diagnostic approaches of SARS-CoV-2, and its pathogenesis will be of great value in designing a long-term strategy to tackle COVID-19.

Chemosensory perception in insects involves a broad set of chemosensory proteins (CSPs) that identify the bouquet of chemical compounds present in the external environment and regulate specific behaviors. The current study is focused on the Spodoptera litura (Fabricius) chemosensory-related protein, SlitCSP3, a midgut-expressed CSP, which demonstrates differential gene expression upon different diet intake. There is an intriguing possibility that SlitCSP3 can perceive food-derived chemical signals and modulate insect feeding behavior. We predicted the three-dimensional structure of SlitCSP3 and subsequently performed an accelerated molecular dynamics (aMD) simulation of the best-modeled structure. SlitCSP3 structure has six α-helices arranged as a prism and a hydrophobic binding pocket predominated by leucine and isoleucine. We analyzed the interaction of selected host plant metabolites with the modeled structure of SlitCSP3. Out of two predicted binding pockets in SlitCSP3, the plant-derived defensive metabolites 2-b-D-glucopyranosyloxy-4-hydroxy-7-methoxy-1, 4-benzoxazin-3-one (DIMBOA), 6-Methoxy-2–benzoxazolinone (MBOA), and nicotine were found to interact preferably to the hydrophobic site 1, compared to site 2. The current study provides the potential role of CSPs in recognizing food-derived chemical signals, host-plant specialization, and adaptation to the varied ecosystem. Our work opens new perspectives in designing novel pest-management strategies. It can be further used in the development of CSP-based advanced biosensors.

Mycobacterium tuberculosis persistence in the host is one of the major challenges towards treating tuberculosis. A dedicated set of lipid metabolism genes enable it to resist anti-tuberculosis drugs. Host TAG accumulation is one such property displayed by Mycobacterium. We analyzed expression profile of mycobacterial genes under stress condition inducing TAG accumulation. TAG accumulation was accompanied by overexpression of Rv1179c. Structural analysis of Rv1179c suggests hydrolase like activity of Rv1179c. Hydrolases are involved in host lipid import and TAG accumulation.

Plants are endowed with an innate immune system, which enables them to protect themselves from pest and pathogen. The participation of pathogenesis-related (PR) proteins is one of the most crucial events of inducible plant defense response. Herein, we report the characterization of CaHaPR-4, a Helicoverpa-inducible class II PR-4 protein from chickpea. Bioinformatic analysis of CaHaPR-4 protein indicated the presence of a signal peptide, barwin domain but it lacks the chitin-binding site/hevein domain. The recombinant CaHaPR-4 is bestowed with RNase and bivalent ion-dependent DNase activity. Further, the RNA and DNA binding sites were identified and confirmed by analyzing interactions between mutated CaHaPR-4 with the altered active site and ribonuclease inhibitor, 5'ADP and DNase inhibitor, 2‑nitro‑5‑thiocyanobenzoic acid (NTCB) using 3D modeling and docking studies. Moreover, CaHaPR-4 shows antifungal activity as well as growth inhibiting properties against neonatal podborer larvae. To the best of our knowledge, this is the first report of a PR-4 showing RNase, DNase, antifungal and most importantly insect growth inhibiting properties against Helicoverpa armigera simultaneously.

Thioredoxins are small and universal proteins, which are involved in the cell redox regulation. In plants, they participate in a broad range of biochemical processes like self-incompatibility, seed germination, pathogen & pest defense and oxidative stress tolerance. The h-type of thioredoxin (Trx-h) protein represents the largest Trx family. Herein, we characterized the Helicoverpa – inducible Trx h from an important legume, Cicer arietinum , CaHaTrx-h, ‘CGFS’ type Trxs, which encodes for a 113 amino acids long protein and possess characteristic motifs “FLKVDVDE” and “VVDFTASWCGPCRFIAPIL” and 73% sequence identity with AtTrx-h. Homology modeling and simulation of the target showed that the extended s-sheet regions remain stable during the simulation while the helical regions fluctuate between alpha and 3- 10 helical forms and highlights the flexibility of helix2-helix3 and terminal regions probably to accommodate an approaching protein target and facilitate their interaction. During the simulation, the structure exists in five energy minima clusters with biggest cluster size belonging to 20–25 ns time frames. PR-5 and Mannitol Dehydrogenase were nominated as potential targets and share close interaction with CaHaTrx-h via disulfide bond reduction. The study is an effort in the direction of understanding stress-related mechanisms in crop plants to overcome losses in agricultural yield.

Mitogen-activated protein kinases (MAPKs) are universal cell signaling components amongst all the eukaryotes and govern critical roles in growth, development and environment adaptation. However, very little information is available about the MAPK family in chickpea. Here, we provide a comprehensive functional analysis of the Mitogen-activated protein kinases (MAPK) family from Cicer arietinum including identification and nomenclature, chromosomal localization, phylogenetic relationships, and investigation of expression analysis in different tissues and in response to abiotic stresses. A genome wide study identified 19 MAPK genes in the chickpea genome, and phylogenetic analysis showed that MAPK family members could be classified into four distinct groups; genes within the same groups had almost similar exon–intron structures. All MAPK proteins in groups A, B and C had a Thr-Glu-Tyr (TEY) activation domain, whereas those in group D contained a Thr-Asp-Tyr (TDY) activation domain. We explored transcriptome data and performed Quantitative real-time (QPCR) analysis, which showed that all the MAPKs were expressed more in flowers and young pods and are rapidly regulated by abiotic stresses and ABA treatment. There was a strong correlation between promoter cis-elements and stress-induced MAPK gene expression. These results contribute to a comprehensive knowledge on MAPKs and their regulation and further assist in functional characterization of MAPK cascades in chickpea.

Insects nurture a panoply of microbial populations that are often obligatory and exist mutually with their hosts. Symbionts not only impact their host fitness but also shape the trajectory of their phenotype. This co-constructed niche successfully evolved long in the past to mark advanced ecological specialization. The resident microbes regulate insect nutrition by controlling their host plant specialization and immunity. It enhances the host fitness and performance by detoxifying toxins secreted by the predators and abstains them. The profound effect of a microbial population on insect physiology and behaviour is exploited to understand the host–microbial system in diverse taxa. Emergent research of insect-associated microbes has revealed their potential to modulate insect brain functions and, ultimately, control their behaviours, including social interactions. The revelation of the gut microbiota–brain axis has now unravelled insects as a cost-effective potential model to study neurodegenerative disorders and behavioural dysfunctions in humans. This article reviewed our knowledge about the insect–microbial system, an exquisite network of interactions operating between insects and microbes, its mechanistic insight that holds intricate multi-organismal systems in harmony, and its future perspectives. The demystification of molecular networks governing insect–microbial symbiosis will reveal the perplexing behaviours of insects that could be utilized in managing insect pests.

RNA interference (RNAi) based methods are being developed for pest management. A few products for control of coleopteran pests are expected to be commercialized soon. However, variability in RNAi efficiency among insects is preventing the widespread use of this technology. In this study, we conducted research to identify reasons for variability in RNAi efficiency among thirty-seven (37) insects belonging to five orders. Studies on double-stranded RNA (dsRNA) degradation by dsRNases and processing of labeled dsRNA to siRNA showed that both dsRNA degradation and processing are variable among insects belonging to different orders as well as among different insect species within the same order. We identified homologs of key RNAi genes in the genomes of some of these insects and studied their domain architecture. These data suggest that dsRNA digestion by dsRNases and its processing to siRNAs in the cells are among the major factors contributing to differential RNAi efficiency reported among insects.

The Mitogen-activated Protein Kinase (MAPK) Cascades play a crucial role in the regulation of defense responses in plants. Herbivory- or wounding-related MAPKs, SA-induced protein kinase (SIPK) and wound-induced protein kinase (WIPK) have been identified to be associated with insect attack. However, function of MAPKs in crop plants in response to herbivory largely remains unknown. Here, we evaluated the expression patterns of fifteen MAPK genes from chickpea in response to infestation by a major pest, Helicoverpa armigera via quantitative real-time PCR (qPCR). Subsequently, we compared the expression patterns of CaMAPKs in response to two related but different processes i.e. insect attack and mechanical wounding. Signaling compounds such as Jasmonates, Salicylic acid and Ethylene also play crucial function in defense response. Therefore, we have also examined the expression profiles of H. armigera -inducible MAPK genes in response to these signaling compounds. Our results revealed that out of fifteen CaMAPKs, seven of the CaMAPKs are upregulated in response to H. armigera and two are downregulated. Additionally, they show differential expression on comparing Helicoverpa -infestation and wounding. Jasmonates and Ethylene mainly regulate CaMAPK genes that may play a role in defense against Helicoverpa -infestation. This study provides insights into the participation of MAPKs in defense against insects.

Plants and herbivores have co-evolved since long and plants have established sophisticated defence mechanisms for their protection. Plant defence response against herbivory involves activation of multiple signalling cascades due to wound-induced change in ion concentration and rapid deviation in the membrane potential (Vm). Amongst all the early events, Ca2+ signalling is one of the most crucial incidents that form a complex network with numerous components. During stress, cytosolic Ca2+ level upsurges due to Ca2+ influx and Ca2+ efflux by Ca2+-ATPases and H+/Ca2+, respectively. This transient change in Ca2+ concentration is identified by Ca2+-sensors [Ca2+-binding proteins such as calmodulin (CaM), CaM-related proteins (CML), calcineurin B-like proteins (CBL)], which relay the signal by stimulating calcium dependent protein kinases (CDPKs). Further, these CDPKs regulate the downstream processes involved in plant defence mechanism. Herbivory not only triggers local Ca2+ signals, rather it also fluctuates systemic Ca2+ levels, which plays a significant role in systemic plant defence. The present chapter highlights the recent advancements in early signalling events during plant–herbivore interaction with special emphasis on Ca2+ signalling, Ca2+ channels, Ca2+-sensors, and Ca2+-responders.

In the present era, the progression of plant development in the environment is adversely affected by increasing incidences of abiotic and biotic stresses. These stressors singly or in combination negatively pose pressure on plants. As a result, the plants display a wide range of morphological, physiological, biochemical, metabolic, molecular as well as epigenetic responses that help them in averting stress-triggered alterations. In addition to “Omics,” plant breeding, functional genomics, transgenic technology, and genome editing approaches, better mineral nutrition coupled with soil-health amendments is still considered as the key management practice. Use of Silicon (Si), the second most predominant and quasi-essential element, has been recommended in the recent past. Si not only promotes growth and development of plants, it also works as “anti-stress agent.” Si mitigates this alleviating effect mainly by ROS detoxification, immobilization, and compartmentation of toxic metal ions, modification in water and nutrients uptake, alteration in gene expression and phytohormone biosynthesis, maintenance of osmotic potential and gaseous exchange, and formation of Si–cuticle double layer. Moreover, being non-corrosive and non-pollutive, Si-supplementation has proven to be the most economic as well as eco-friendly method. The present chapter is an attempt to primarily address the involvement of Si in minimizing the negative effects of abiotic stresses.