Abstract
The whitefly Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) is an important pest of cotton in many countries including Pakistan. Even though it has gained resistance for various registered insecticides such as the neonicotinoid insecticide thiamethoxam, the cellular changes occurring in plants during whitefly infestation and resistance are poorly understood. In particular, the proteomic analysis of interaction between cotton plant and devastating whiteflies is poorly understood. To reveal the physiological response as well as the molecular interaction during the incursion of B. tabaci, one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1-D SDS-PAGE) following liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was conducted, combined with in silico protein characterizations and protein-protein interaction following validation of LC-MS/MS results by quantitative real-time PCR. The shotgun proteomic analysis of cotton leaves infested with whitefly resulted in the identification of 38 proteins, and 24 under control (non-infested) conditions. Of them, 11 proteins were identified as shared proteins, 13 were differentially induced in non-infested conditions, and 27 were induced only under whitefly-infested conditions. The major proteins like MAP kinases, COBRA-like protein family, and NBS disease resistance protein were expressed under infested conditions; while the heat shock protein 90 and cyclic nucleotide-gated ion channel 5-like major proteins were expressed under whitefly non-infested conditions. The current manuscript presents new insights into the mechanism of whitefly infestation and our understanding of the roles of COB and COBLs in host-pest interaction. To the best of our knowledge, this is the first ever report to reveal the role of several proteins, including COB and COBLs in host-pest leaf interaction.