Heat Shock Proteins expression in malaria and dengue vector

The survival of mosquitoes under changing climatic conditions particularly temperature, is known to be supported by Heat Shock Proteins (HSPs). In view of climate change, it is imperative to know whether the mosquito vectors will be able to withstand the increased temperatures or perish. Therefore, the present study was undertaken on the expression of HSPs' gene in An. stephensi and Ae. aegypti by exposing them to temperatures ranging from 5 to 45°C for 15-180-minutes for once and continuously or with rest in between. We compared the temperature-tolerance of both the vectors in terms of expression of HSP83, HSP70, and HSP26 genes at varying degrees of temperature and duration. HSP70 and HSP26 were found distinctively expressed in both the vectors as compared to HSP83. With continuous exposure up to 180-minutes at 35°C and 40°C, HSP70 was found upregulated up to 35 and 47 folds in Ae. aegypti while in An. stephensi, the expression was only 1 fold. Between the genes, HSP70 was highly expressed at different temperatures followed by HSP26 and HSP83. The manifold up-regulation of HSP genes in Ae. aegypti than An. stephensi may be attributed to the robustness of Aedes vector in terms of temperature tolerance. This study has shown that Ae. aegypti and An. stephensi can withstand considerable temperature stress by expressing HSPs when exposed to variable temperature and duration. In view of changing climate, the study provides a clue that the vector of dengue and zika virus will be difficult to control.