Author
BANSAL, RAMAN - The Ohio State University | |
Mian, Rouf | |
MITTAPALLI, OMPRAKASH - The Ohio State University | |
MICHEL, ANDREW - The Ohio State University |
Submitted to: Bulletin of Entomological Research
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/10/2012 Publication Date: 2/28/2012 Citation: Bansal, R., Mian, R.M., Mittapalli, O., Michel, A.P. 2012. Molecular characterization and expression analysis of soluble trehalase gene in Aphis glycines, a migratory pest of soybean. Bulletin of Entomological Research. 103(3):286-295. Interpretive Summary: The soybean aphid is the most damaging insect pest of soybean in USA. The dispersal of soybean aphids depends heavily on flights of winged aphids. In insects, trehalase plays a crucial role in energy metabolism as well as chitin synthesis. There is no report on the characterization of trehalase gene in aphids which are serious pests of various agricultural crops. We have characterized a soluble trehalase gene (Tre-1) from cDNA of soybean aphid. The full-length cDNA of Tre-1 in aphid (AyTre-1) was 2550bp long with an open reading frame of 1770 bp that encoded for a 589 amino acid residues protein. Real-time PCR analysis revealed ~2X increase in expression of AyTre-1 in the alate morphs of aphid, as compared to that observed in apterate morphs. Tissue expression analysis revealed peak mRNA levels of AyTre-1 in gut of aphids and moderate in the other tissues assayed. Similarly, expression analysis in different developmental stages of aphids revealed that AyTre-1 was expressed in all stages but had the highest expression in second instar stage. Results obtained in the current study indicated a major role for soluble trehalase during flight activity of aphids. Further, the characterization of soluble trehalase gene provides a platform for novel strategies to manage soybean aphid in field using trehalase inhibitors and using RNAi for knock-down of AyTre-1 expression as an alternative to chemical control of the aphid. Technical Abstract: Trehalase catalyzes the hydrolysis of trehalose, a disaccharide sugar into two glucose molecules. In insects, trehalase plays a crucial role in energy metabolism as well as chitin synthesis. There is no report on the characterization of trehalase gene in aphids which are serious pests of various agricultural crops. We have characterized a soluble trehalase gene (Tre-1) from cDNA of Aphis glycines, a serious migratory pest of soybean. The full-length cDNA of Tre-1 in A. glycines (AyTre-1) was 2550bp long with an open reading frame of 1770 bp that encoded for a 589 amino acid residues protein. The deduced amino acid sequence of AyTre-1 contained typical catalytic residues as well as both of the signature sequences present in soluble trehalases of insects. Real-time PCR analysis revealed ~2X increase in expression of AyTre-1 in the alate morphs of A. glycines, as compared to that observed in apterate morphs. Expression analysis of AyTre-1 in A. glycines nymphs fed with resistant and susceptible plants revealed no differences. Tissue expression analysis revealed peak mRNA levels of AyTre-1 in gut of A. glycines and moderate in the other tissues assayed. Similarly, expression analysis in different developmental stages of A. glycines revealed that AyTre-1 was expressed in all stages but had the highest expression in second instar stage. Results obtained in the current study indicated a major role for soluble trehalase during flight activity of A. glycines. Further, the characterization of soluble trehalase gene provides a platform for novel strategies to manage A. glycines in field using trehalase inhibitors and using RNAi for knock-down of AyTre-1 expression. |