Submitted to: Insect Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/10/2011
Publication Date: 8/3/2011
Citation: Garczynski, S.F., Wanner, K., Unruh, T.R. 2011. Identification and initial characterization of the 3' end of gene transcripts encoding putative members of the pheromone receptor sub-family in Lepidoptera. Insect Science. 19:64-74. Interpretive Summary: Caterpillars of many species of moths are among the most destructive pests of agricultural crops. Scientists at the USDA-ARS Yakima Agricultural Laboratory in Wapato, WA in conjunction with researchers at Montana State University are conducting research to better understand the sense of smell in major pests of tree fruit such as the codling moth, obliquebanded leafroller and light brown apple moth. A new method was developed to identify pheromone receptors in the major moth pests of agriculture. The information in this manuscript provides scientists the information and technology they need to identify protein receptors of pheromones and kairomones, improving our understanding of the sense of smell in insect pests. This line of research will assist efforts to make more potent semiochemicals for use in orchards in the Pacific Northwest as well as other agricultural crops worldwide.
Technical Abstract: Semiochemicals, including pheromones and kairomones, used in pest management programs reduce the need for chemical insecticides, and understanding their interactions with their membrane receptor will help make them more effective in the field. Identification of odorant receptors in the Lepidoptera has mainly been achieved using bioinformatics to search DNA sequences generated by genome or EST sequencing projects. This study reports a rapid method to identify members of the pheromone receptor subfamily in Lepidoptera. Degenerate oligonucleotide primers were designed against a conserved amino acid sequence in the carboxyl terminus of known lepidopteran pheromone receptors, and the primers were used in a 3’ rapid amplification of cDNA ends procedure. PCR products generated from seven different lepidopteran species were TA cloned and sequenced. The cDNA sequences of 25 transcripts were determined to encode potential members of the pheromone receptor subfamily. These cDNAs ranged from 238 - 642 bp and encoded 49-54 amino acids of the carboxyl terminus. Analysis of the 3’ untranslated region reveals that most of the transcripts have multiple polyadenylation signal sequences, and in the case of Manduca sexta, an alternate polyadenylation signal appears to be used in transcript processing. The 3’ untranslated region was also useful in determining unique receptors encoded by transcripts having highly similar nucleotide and amino acid sequences. Overall, this technique provides a complementary method of pheromone receptor identification in EST sequencing projects, or can be used as a stand-alone method in conjunction with 5’ rapid amplification of cDNA ends procedures.