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The fall army worm (FAW) (Spodoptera frugiperda) is a polyphagous pest which causes damage to commercially important cultivated crops such as maize, rice, sorghum, cotton and also different vegetable crops. Carboxyl esterases (CarE, EC.3.1.1.1) or esterases are enzymes in the carboxyl / cholinesterase gene family that catalyze the hydrolysis of carboxyl esters. The carboxylesterases enzyme are the detoxification enzymes in FAW. Therefore, the inhibition of carboxylesterases from FAW would help in pest management. In this scenario, Isolation, purification and inhibition studies were carried out on the midgut carboxylesterase enzyme of FAW. Through a combination of steps including centrifugation, ammonium sulfate gradient precipitation, DEAE-Cellulose ion exchange chromatography, the enzyme was purified from fifth instar larvae of FAW. The final purified carboxylesterase after ion exchange chromatography had a specific activity of 7282.22 units / mg protein, 5.6 – fold of crude homogenate, and a yield of 25%. The purity of esterase was established by PAGE and SDS-PAGE. The SDS-PAGE revealed a molecular weight of approximately 45kDa to 66kDa. Our studies on the purified midgut carboxylesterase showed complete inhibition by organophosphorous inhibitor (10-4 M). The enzyme was also inhibited by 1x concentration of Lizol (disinfectant) and by different natural extracts (1x) as well.

French bean is (Phaseolus vulgaris) widely grown legume worldwide and is the most important pulse crop in the Indian subcontinent. The productivity is adversely affected by a large number of biotic and abiotic stresses. Micro RNAs (miRNAs) have been implicated in the regulation of plant responses to several biotic and abiotic stresses. Boron (B) toxicity is a significant limitation to cereal crop production worldwide. In this study, RT-qPCR confirmed seven miRNAs were responsive to boron toxicity. The known predicted targets and their functional analysis revealed that most of the targets represent transcription factors. GO results supported our hypothesis that miRNAs were found to be involved in diverse cellular processes, including plant circadian cycle, vegetative development, transcription, and cross adaptation. The results obtained would provide new insights to the complex regulatory mechanism employing small non-coding regulatory RNAs toward stress adaptation.

MicroRNAs (miRNAs) play important roles in plant responses to abiotic stress. Numerous studies have been increasing in respect to miRNA identification under stress conditions. In this study we analysed the expression patterns of seven miRNAs (miR156, 159, 169, 396, 397, 398 and 399) from cadmium stressed seedlings of Finger millet by RT-qPCR. Further these miRNAs were cloned and sequenced, which conformed its presence. Predicted targets and GO analysis of the miRNAs were found to be involved in diverse cellular processes in plants, development, apoptosis, detoxification, catalysis, protein modification. Cis-regulatory elements identification suggested their involvement in regulatory networks. This is the first study to demonstrate differentially expressed miRNA in Finger millet under cadmium stress. Findings in the present study prominence the role played by miRNAs in Finger millet under cadmium stress.

Groundnut (Arachis hypogaea L.), is an important subsistence oil yielding crop of the semi-arid tropics and often exposed to several environmental cues (high temperature, drought & heavy metal). Transcription factors can control the expression of many target genes through specific binding to the cis-acting elements in the promoters of the target genes. The basic leucine zipper (bZIP) and basic helix-loop-helix (bHLH) represents one of the largest as well as most diverse transcription factor (TFs) families. They are known to play role in both stress as well as in various plant developmental processes. In this study, a comprehensive phylogeny, chromosomal location, conserved motif identification and expression profiles under high temperature and drought stress. of bZIP and bhLH TF gene family was carried in groundnut. A total of 151 bZIP and 39 bHLH transcription factors have been identified from groundnut. Expression analysis during high temperature and heavy metal stress conditions. Gene expression studies revealed differential expressions of bZIP and bhLH TFs suggesting the possible role in various stress mitigation and can serve as a candidate genes for improving abiotic stress.

Carboxyl esterase (E.C.No.3.1.1.1) was partially purified from Adenanthera pavonina (Saga) using ammonium sulfate fractionation (0-60%) and DEAE (diethyl aminoethyl) ion exchange chromatography, the purified enzyme was characterized. One major saga-esterase was identified with Fold purification of 29. Molecular weight of the Ap-esterase was determined using Sephadex G-25 gel filtration and SDS-PAGE (Sodium dodecyl sulfate polyacryamide gel electrophoresis) which was found to be 26.0 k Da. Optimal activity of the saga-esterase occurred when the pH 7.0 at a temperature of 55°C. The activation energy for the hydrolysis of α-naphthyl acetate was determined to be 1.10 kcal/ mol. The Michaelis Menton constant (Km) and Vmax of the saga-esterase was 0.4µmoles and 105 IU respectively. In addition, the isoelectric point is at pH > 9 and immuno-blot using polyclonal antibodies showed that the saga-esterase was widely distributed in seeds but not in leaves. The saga-esterase inhibited by organophosphate and carbamate pesticides, which can be substituted for acetylcholinesterase.

In order to identify the components of high temperature response in French bean, three heat shock proteins induced under high temperature were purified to homogeneity by Carboxy methyl cellulose and sephadex G-100 chromatography followed by preparative SDS-PAGE. Two of these, Hsp1 and Hsp3 were further characterized by immuno-detection with polyclonal antibodies. Hsp3 exhibited ATPase and chaperone activity with malate dehydrogenase and citrate synthase. Partial cDNA for Hsp3 synthesized using the primer derived from amino-terminal sequence was cloned and expressed in Escherichia coli. The recombinant protein possesses ATPase activity, and showed thermal protection at 50°C in Escherichia coli. The translated partial cDNA showed homology with stress induced proteins including ATPases from higher plants. These results supported the fact that French bean response to high temperature stress involves Hsps as one of the principal components.