Molecular and Functional Characterization of Trehalase in the Mosquito Anopheles stephensi
Sanjay Tevatiya, Seena Kumari, Punita Sharma, Jyoti Rani, Charu Chauhan, Tanwee Das De, Kailash C. Pandey, Veena Pande, Rajnikant Dixit
Abstract
Like other insects, in blood-feeding mosquitoes, trehalase (TRE; EC 3.2.1.28), an enzyme that metabolizes trehalose, may influence a wide array of functions including flight, survival, reproduction, and vectorial capacity, but its role has not been investigated in detail. Here, we characterized a 1839 bp long transcript, encoding 555 aa long trehalase-2 homolog protein from the mosquito Anopheles stephensi. With a conserved insect homology, and in silico predicted membrane-bound protein, we tested whether trehalase (As-TreH) also play a role in mosquito physiologies. Constitutive expression during aquatic development or adult mosquito tissues, and a consistent up-regulation until 42 hrs of starvation, which was restored to basal levels after sugar supply, together indicated that As-TreH may have a key role in stress tolerance. A multifold enrichment in the midgut (p< 0.001819) and salivary glands (p<4.37E-05) of the Plasmodium vivax-infected mosquitoes indicated that As-TreH may favor parasite development and survival in the mosquito host. However, surprisingly, after the blood meal, a consistent up-regulation until 24hr in the fat body, and 48hr in the ovary, prompted to test its possible functional correlation in the reproductive physiology of the adult female mosquitoes. A functional knockdown by dsRNA-mediated silencing confers As-TreH ability to alter reproductive potential, causing a significant loss in the egg numbers (p<0.001), possibly by impairing energy metabolism in the developing oocytes. Conclusively, our data provide initial evidence that As-TreH regulates multiple physiologies and may serve as a suitable target to designing novel strategies for vector control.