Location: Pest Management and Biocontrol Research
Title: Molecular and functional characterization of multiple aquaporin water channel proteins from the western tarnished plant bug, Lygus hesperus Authors
Submitted to: Insect Biochemistry and Molecular Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 1, 2013
Publication Date: February 1, 2014
Citation: Fabrick, J.A., Pei, J., Hull, J.J., Yool, A.J. 2014. Molecular and functional characterization of multiple aquaporin water channel proteins from the western tarnished plant bug, Lygus hesperus. Insect Biochemistry and Molecular Biology. 45:125-140. Interpretive Summary: Lygus hesperus (the western tarnished plant bug) is an important pest in Western North America, causing damage to cotton, alfalfa, beans, and numerous fruit and vegetable crops. Lygus bugs damage crops by injecting plants with saliva containing enzymes that digest plant tissue. The pre-digested fluid is then taken up by the feeding bug and the nutrients are absorbed within the gut. Because lygus bugs thrive in the water-limited enivronment of the Southwestern US and are highly adapted to feed exclusively on a liquid diet, they must have highly adapted systems for regulation of water balance. Indeed, water transport is a universal requirement for living cells and water channel proteins (known as aquaporins) are important facilitors of water through and among cells. Here, we used molecular and biochemical techniques to characterize five new aquaporins from L. hesperus. The five lygus aquaporins differ in when and where they are produced within the body, but all have similar ability to transport water. These proteins and the mechanisms that regulate water balance in the lygus bug represent promising areas of research for the development of new pest controls.
Technical Abstract: Aquaporins (AQPs) are integral membrane channel proteins that facilitate the bidirectional transfer of water or other small solutes across biological membranes involved in numerous essential physiological processes. In arthropods, AQPs belong to several subfamilies, which contribute to osmoregulation, respiration, cryoprotection, anhydrobiosis, and excretion. We cloned and characterized five novel AQPs from the western tarnished plant bug, Lygus hesperus, a polyphagous insect pest of food and fiber crops throughout western North America. The L. hesperus AQPs (LhAQP1-5) belong to different phylogenetic subfamilies, have unique transcription profiles and cellular localizations, and all transport water (but not glycerol) when heterologously expressed in Xenopus laevis oocytes. Our results demonstrate that multiple AQPs with possible compensatory functions are produced in L. hesperus that likely play important roles in maintaining water homeostasis in this important insect pest.