Submitted to: Insect Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/5/2012
Publication Date: 9/17/2013
Publication URL: http://handle.nal.usda.gov/10113/58284
Citation: Garczynski, S.F., Coates, B.S., Unruh, T.R., Schaeffer, S., Jiwan, D., Koepke, T., Dhingra, A. 2013. Application of Cydia pomonella expressed sequence tags: identification and expression of three general odorant binding proteins in codling moth. Insect Science. 20(5):559-574. Interpretive Summary: Control of codling moth, a major pest of apple and pear, is mainly achieved using a series of chemical insecticide applications, and this form of control presents hazards to the environment, workers and consumers. To reduce chemical insecticide use in the orchard, many orchardists are using mating disruption (permeation of sex pheromones throughout the orchard which prevents males from locating females) as part of an integrated pest management strategy for control of moth pests. Researchers at the USDA-ARS Yakima Agricultural Research Laboratory (Wapato, WA) and Corn Insect and Crop Genetics Research Unit (Ames,IA), and Washington State University (Pullman, WA) have used next generation sequencing to determine gene expression in various codling moth tissues that respond to semiochemicals. Gene transcripts that encode 30 proteins important in the detection of semiochemicals, including sex pheromones, were identified and characterized. This work provides a source of DNA sequences and the proteins that they encode which are important in the detection of semiochemicals such as pheromones. These genes and proteins are prime biochemical targets for developing enhanced methods of codling moth control without the use of hazardous insecticides.
Technical Abstract: The codling moth, Cydia pomonella, is one of the most important pests of pome fruits in the world, yet the molecular genetics and physiology of this insect remains poorly understood. A combined assembly of 8340 expressed sequence tags (ESTs) was generated from Roche 454 GS-FLX sequencing of 8 tissue specific cDNA libraries. Putative chemosensory proteins (12) and odorant binding proteins (18) were annotated, which included 3 putative general odorant binding proteins (GOBPs), one more than typically found in other Lepidoptera. To further characterize CpomGOBPs, we cloned cDNA copies of their transcripts and determined their expression patterns in various tissues. Cloning and sequencing of the 698 nt transcript for CpomGOBP1 resulted in the prediction of a 163 amino acid coding region, and subsequent RT-PCR indicated that the transcripts were mainly expressed in antennae and mouthparts. The 1289 nt (160 amino acids) CpomGOBP2 and the novel 702 nt (169 amino acids) CpomGOBP3 transcripts are mainly expressed in antennae, mouthparts and female abdomen tips. The results of our EST project indicate that next generation sequencing is useful for the characterization of novel transcripts of interest, and that codling moth expresses a transcript encoding for a new member of the GOBP protein subfamily.