A study of responses of the invasive apple snail Pomacea canaliculata to environmental stressors using shotgun proteomics

Studying physiological adaptation to environmental stress at molecular level can help us understand why some species can live in extreme environments, predict the impact of environmental change on the distribution of a species, and discover the evolutionary course of stress tolerance. This study aims to understand the molecular mechanisms of adaptation to several environmental stressors (desiccation, heat and hypoxia) in the apple snail Pomacea canaliculata, an invasive species native to South America now widely distributed in freshwater wetlands of Asia, causing tremendous loss to the rice and vegetable agriculture. We will compare the proteomic responses of P. canaliculata to desiccation, heat and hypoxia under normal and stressed conditions. For each stressor, a time-course study will be conducted to distinguish immediate and prolonged responses, and to test a specific working hypothesis (e.g. roles of the uric acid cycle for desiccation resistance). In addition, we will determine how Pomacea canaliculata (invasive species) and Pomacea diffusa (non-invasive species) respond differently to the same level of stress. The samples will be labeled using an isobaric tagging method, and the differentially expressed proteins will be identified through shotgun quantitative proteomics, followed by determination of protein functional pathways involved in stress responses. To confirm the up- or down-regulation of a set of differentially expressed proteins, RNA will be extracted and Real-Time PCR will be performed. Overall, this study will allow us to gain insight into the molecular mechanisms of adaptation in P. canaliculata, which may help us understand why it is invasive while its congener P. diffusa is non-invasive. The proteomic data from this study may laid a foundation for further research leading to biological control of the pest using immunocontraception.