Aquaporin identification and analysis in the Asian citrus psyllid (Diaphorina citri) and the potato psyllid (Bactericera cockerelli)

        Phloem feeding insects must overcome a major problem: how to avoid dehydration as they feed. In aphids and whiteflies, it has been shown that osmotic pressure from ingested phloem is lowered by water circulation through the gut and other mechanisms, such as rapid transglucosidation. Water transport proteins, known as aquaporins, have been shown to be linked to water circulation within aphid and whitefly guts. Diaphorina citri, the Asian citrus psyllid, and Bactericera cockerelli, the potato psyllid, are two economically important pests because they are responsible for vectoring the bacteria that cause Huanglongbing (Citrus Greening) and Zebra Chip, respectively. In this project, putative aquaporin genes in D. citri and B. cockerelli were studied since water transport might not only play an important role in phloem feeding in these insects, but also in pathogen transmission. Candidate genes were found using the available genomic data. Full coding sequences and potential splicing forms were identified using Rapid Amplification of cDNA Ends (RACE). The expression patterns of candidate genes were studied by reverse transcription in specific tissues, and the spatial expression within the insects is being analyzed via in situ hybridizations. Results from this project might help elucidating physiological adaptations of the insects to phloem feeding and might pave the way to develop new strategies to control insect vectors and the pathogens they transmit.