Transcript variation, sequence validation, and expression profiling of behavior-linked slowmo, shaker, foraging, and ptp gene homologs in the European corn borer, Ostrinia nubilalis

The movement and dispersal of larval Lepidoptera are factors that govern their survival and distribution within the natural landscape. Homologs of the Drosophila behavior-linked genes slowmo, shaker, foraging and ptp involved in motor locomotion were identified from the European corn borer, Ostrinia nubilalis (Lepidoptera: Crambidae). 5¢ and 3¢ RACE products indicate that 3 slowmo transcript splice variants are present in O. nubilalis tissues (640 nt, 970 nt, and 1602 nt). The 142-228 encoded amino acid proteins show significant homology to the Drosophila mitochondrial slowmo protein isoform B (E-value 10^-64). A 2110 nt transcript was isolated from neurological tissue of O. nubilalis, which is predicted to encode a 474 amino acid protein exhibiting 72% nucleotide and 92% protein identity with the Drosophila shaker potassium channel (isoforms E and C). Fragments of the O. nubilalis foraging and ptp genes have also been isolated and validated by sequencing. RACE reactions are underway to complete full length transcripts of these genes. Slowmo, shaker, foraging, and ptp were expressed in embryonic through adult life stages, and within all individual tissues tested, suggesting an essential role in physiological function. Future studies are directed at investigating behavioral protein functions with regard to naturally occurring phenotypes in the field. Our aim is to understand the relationships between ECB behavior and the potential environmental adaptations that may be under selection in O. nubilalis populations exposed to transgenic crops.