@article { ISI:000296414700021, title = {Assimilatory potential of helicoverpa armigera reared on host (chickpea) and nonhost (cassia tora) diets}, journal = {Journal of Proteome Research}, volume = {10}, number = {11}, year = {2011}, month = {NOV}, pages = {5128-5138}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Adaptation to plant allelochemicals is a crucial aspect of herbivore chemical ecology. To understand an insect ecology, we studied an effect of nonhost Cassia tora seed-based diet (Ct) on growth, development, and molecular responses in Helicoverpa armigera. We employed a comparative approach to investigate the proteomic differences in gut, hemolymph, and frass of H. armigera reared on a normal (chickpea seed-based, Cp) and Ct diet. In this study, a total of 46 proteins were identified by nano-LC-MS(E). Among them, 17 proteins were up-regulated and 29 proteins were down-regulated when larvae were exposed to the Ct diet. Database searches combined with GO analysis revealed that gut proteases engrossed in digestion, proteins crucial for immunity, adaptive responses to stress, and detoxification were down-regulated in the Ct fed larvae. Proteins identified in H. armigera hemolymph were found to be involved in defense mechanisms. Moreover, proteins found in frass of the Ct fed larvae were observed to participate in energy metabolism. Biochemical and quantitative real-time PCR analysis of selected candidate proteins showed differential gene expression patterns and corroborated with the proteomic data. Our results suggest that the Ct diet could alter expression of proteins related to digestion, absorption of nutrients, adaptation, defense mechanisms, and energy metabolism in H. armigera.

}, keywords = {adaptation, Cassia tora, Gene expression, Helicoverpa armigera, proteomics}, issn = {1535-3893}, doi = {10.1021/pr200591m}, author = {Dawkar, Vishal V. and Chikate, Yojana R. and Gupta, Vidya S. and Slade, Susan E. and Giri, Ashok P.} } @article { ISI:000326615000007, title = {Molecular insights into resistance mechanisms of lepidopteran insect pests against toxicants}, journal = {Journal of Proteome Research}, volume = {12}, number = {11}, year = {2013}, month = {NOV}, pages = {4727-4737}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Insect pests remain a major reason for crop loss worldwide despite extensive use of chemical insecticides. More than B 50\% of all insecticides are organophosphates, followed by synthetic pyrethroids, organochlorines, carbamates, and biopesticides, and their continued use may have many environmental, agricultural, medical, and socioeconomic issues. Importantly, only a countable number of insects have acquired the status of crop pests, mostly due to monoculture of crop plants and polyphagous nature of the insects. We focus on A adaptations of Lepidopteran insects to phytochemicals and synthetic pesticides in native and modern agricultural systems. Because of heavy use of chemical insecticides, a strong selection pressure is imposed on insect populations, resulting in the emergence of resistance against candidate compound(s). Current knowledge suggests that insects generally implement a three-tier system to overcome the effect of toxic compounds at physiological, biochemical, and genetic levels. Furthermore, we have discussed whether the adaptation to phytochemicals provides an advantage to the insect while encountering synthetic insecticide molecules. Specific metabolic pathways employed by insects to convert deterrents into less toxic forms or their removal from the system are highlighted. Using the proteomics approach, insect proteins interacting with insecticides can be identified, and their modification in resistant insects can be characterized. Also, systems biology studies can offer useful cues to decipher the molecular networks participating in the metabolism of detrimental compounds.

}, keywords = {field crops, insect-pests, insecticide, Lepidoptera, proteomics, resistance mechanisms}, issn = {1535-3893}, doi = {10.1021/pr400642p}, author = {Dawkar, Vishal V. and Chikate, Yojana R. and Lomate, Purushottam R. and Dholakia, Bhushan B. and Gupta, Vidya S. and Giri, Ashok P.} } @article { ISI:000368829000007, title = {Expression of proteins involved in digestion and detoxification are regulated in helicoverpa armigera to cope up with chlorpyrifos insecticide}, journal = {Insect Science}, volume = {23}, number = {1}, year = {2016}, month = {FEB}, pages = {68-77}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Helicoverpa armigera is a key pest in many vital crops, which is mainly controlled by chemical strategies. To manage this pest is becoming challenging due to its ability and evolution of resistance against insecticides. Further, its subsequent spread on nonhost plant is remarkable in recent times. Hence, decoding resistance mechanism against phytochemicals and synthetic insecticides is a major challenge. The present work describes that the digestion, defense and immunity related enzymes are associated with chlorpyrifos resistance in H. armigera. Proteomic analysis of H. armigera gut tissue upon feeding on chlorpyrifos containing diet (CH) and artificial diet (AD) using nano-liquid chromatography-mass spectrometry identified upregulated 23-proteins in CH fed larvae. Database searches combined with gene ontology analysis revealed that the identified gut proteins engrossed in digestion, proteins crucial for immunity, adaptive responses to stress, and detoxification. Biochemical and quantitative real-time polymerase chain reaction analysis of candidate proteins indicated that insects were struggling to get nutrients and energy in presence of CH, while at the same time endeavoring to metabolize chlorpyrifos. Moreover, we proposed a potential processing pathway of chlorpyrifos in H. armigera gut by examining the metabolites using gas chromatography-mass spectrometry. H. armigera exhibit a range of intriguing behavioral, morphological adaptations and resistance to insecticides by regulating expression of proteins involved in digestion and detoxification mechanisms to cope up with chlorpyrifos. In these contexts, as gut is a rich repository of biological information; profound analysis of gut tissues can give clues of detoxification and resistance mechanism in insects.

}, keywords = {chlorpyrifos, Helicoverpa armigera, insecticide resistance, proteomics, real-time PCR}, issn = {1672-9609}, doi = {10.1111/1744-7917.12177}, author = {Dawkar, Vishal V. and Chikate, Yojana R. and More, Tushar H. and Gupta, Vidya S. and Giri, Ashok P.} } @article { ISI:000378741200010, title = {Fusarium oxysporum mediates systems metabolic reprogramming of chickpea roots as revealed by a combination of proteomics and metabolomics}, journal = {Plant Biotechnology Journal}, volume = {14}, number = {7}, year = {2016}, month = {JUL}, pages = {1589-1603}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Molecular changes elicited by plants in response to fungal attack and how this affects plant-pathogen interaction, including susceptibility or resistance, remain elusive. We studied the dynamics in root metabolism during compatible and incompatible interactions between chickpea and Fusarium oxysporum f. sp. ciceri (Foc), using quantitative label-free proteomics and NMR-based metabolomics. Results demonstrated differential expression of proteins and metabolites upon Foc inoculations in the resistant plants compared with the susceptible ones. Additionally, expression analysis of candidate genes supported the proteomic and metabolic variations in the chickpea roots upon Foc inoculation. In particular, we found that the resistant plants revealed significant increase in the carbon and nitrogen metabolism; generation of reactive oxygen species (ROS), lignification and phytoalexins. The levels of some of the pathogenesis-related proteins were significantly higher upon Foc inoculation in the resistant plant. Interestingly, results also exhibited the crucial role of altered Yang cycle, which contributed in different methylation reactions and unfolded protein response in the chickpea roots against Foc. Overall, the observed modulations in the metabolic flux as outcome of several orchestrated molecular events are determinant of plant{\textquoteright}s role in chickpea-Foc interactions.

}, keywords = {Chickpea, fusarium oxysporum, Metabolomics, NMR, plant-pathogen interaction, proteomics}, issn = {1467-7644}, doi = {10.1111/pbi.12522}, author = {Kumar, Yashwant and Zhang, Limin and Panigrahi, Priyabrata and Dholakia, Bhushan B. and Dewangan, Veena and Chavan, Sachin G. and Kunjir, Shrikant M. and Wu, Xiangyu and Li, Ning and Rajmohanan, Pattuparambil R. and Kadoo, Narendra Y. and Giri, Ashok P. and Tang, Huiru and Gupta, Vidya S.} }