Skip to main content
ARS Home » Midwest Area » Ames, Iowa » Corn Insects and Crop Genetics Research » Research » Publications at this Location » Publication #255478
Title: Transcript analysis and comparative evaluation of shaker and slowmo gene homologues from the European corn borer, Ostrinia nubilalis

Author
item Kroemer, Jeremy
item NUSAWARDANI, TYASNING - Iowa State University
item RAUSCH, MICHAEL - Iowa State University
item Moser, Susan
item Hellmich Ii, Richard

Submitted to: Insect Molecular Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/15/2011
Publication Date: 6/15/2011
Citation: Kroemer, J.A., Nusawardani, T., Rausch, M.A., Moser, S.E., Hellmich II, R.L. 2011. Transcript analysis and comparative evaluation of shaker and slowmo gene homologues from the European corn borer, Ostrinia nubilalis. Insect Molecular Biology. 20(4):493-506.

Interpretive Summary: The manner in which agricultural pests behave in the field can have widespread impacts on the methods used to manage them, and on the sustainability of control measures being utilized or under evaluation for a particular species. Recent research has uncovered that European corn borer larvae tend to be genetically predisposed to dispersing (50%) or remaining (50%) on host plant tissue following egg emergence. In this study, we have described the expression patterns, mRNA transcripts, and encoded proteins for two behavior-linked genes (slowmo and shaker) isolated from the European corn borer (Ostrinia nubilalis) that show homology with known behavior-linked genes from the fruit fly (Drosophila melanogaster). We are ultimately interested in uncovering and monitoring the genetic elements governing larval dispersal and movement behavior in the European corn borer, as the ability of the larvae to disperse or move on transgenic plants is expected to directly impact the effectiveness of mixed seed Bt refuge strategies under evaluation for field release. These studies also provide new valuable molecular tools for evaluating field populations of corn borer for behavioral genotyping. Understanding the molecular basis for behavioral changes and larval movement in the field will aid in elucidating the effectiveness of current resistance management strategies, and enhance our understanding of pest behavioral evolution in high-stress Bt field environments. This information will be valuable to all scientists interested in delaying the development of resistance by lepidopteran pests to genetically-engineered crops.

Technical Abstract: 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 and shaker involved in larval 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 equal to or less than 10(-64)]. Secondly, 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 gene (isoforms E and C). Linkage analysis using segregating single nucleotide polymorphism (SNP) markers indicated that slowmo is an autosomal locus in B. mori and O. nubilalis genomes, whereas shaker is a sex-linked gene located onto the O. nubilalis Z chromosome. Slowmo and shaker were expressed in embryonic through adult stages, and within all individual tissues tested, suggesting an essential role in physiological function.