Progress 05/01/14 to 04/30/19
Outputs
Target Audience:The audience for this research includes industry, government and academic scientists and organizations nationally and internationally that seek to dedvelop new and novel pest management technologies based on a better understanding of the molecular mechanisms of pest insect olfaction. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Brent Herdlicka (MS biochemistry)worked as a research associate on the projectand received trainingin the application of molecular genetic methods to solve research problems in agriculture. After finishingthis workBrent Herdlicka went on to work in a plant molecular biology lab at the University of Washington in Seattle. Several undergraduate workers received training as research assistants. Most notable Alexis Hatton went on to enroll in a PhD program at Montana State University in the Molecular BioSciences Program. How have the results been disseminated to communities of interest?These results are of primary interest to industry, government and academic scientists working to develop novel pest management tools based on knowledge of the molecular mechanisms of odor detection by insect olfactory neurons. The results have been disseminated to these communities through national and international scientific publications and presentations as listed in the products section. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The main molecularcomponents of pheromone signaling in the olfactory system of corn borer moths (ORs, ORCO, SNMP and PBP)were cloned and expressed in theXenopusoocyte system in order to assess their individual contributions to pheromone signaling kinetics. An effectiveprotocol was developed to express and purify PBPs in their native soluble form. Experiments that co-injected SNMP and ORs into Xenopus oocytesfound no effect on the specificity of pheromone signaling compared to oocytes expressing the ORs alone. Purified PBPs were added to the assay with oocytes expressing an OR alone or in combination with SNMP, and no changes in the specificity of pheromone signaling was observed. These results suggested that PBPs from the corn borer moth were not having an impact on the specificity of pheromone signaling, and that the ORs were the primary determinant of specificity, contrary to an earlier published reportusing a different moth species. Subsequent experiments focusedon developing novel experimental protocols to carefully and further test the role of expressed and purified PBPs for their ability to increase the sensitivity of OR activation kinetics by pheromones and their ability to influence the specificity of the response. A protocol was developed to first load pheromone onto a size exclusion column and subsequently pass the purified PBP over the column to demonstrate it would absorb the pheromone from the column. Pheromone was incubated with PBP in molar excess and presented to oocytes expressing ORs. These experiments clearly demonstrated that the corn borer PBPs were not increasing sensitivity of pheromone activation by the ORs nor were they altering specificity of activation, contrary to a previously published result. Given that this was a significant finding, a second set of experiments developed a new and novel technique to assay the effects of PBPs on pheromone transport. Pheromones were immobilized (adsorbed) onto a hydrophobic membrane. When placed into a buffer solution the pheromones did not go into solution and activate the ORs expressed in Xenopus oocytes. However, the addition of PBPs to the mixture enabled the pheromone to be dissolved from the hydrophobic membrane (that mimics pheromone bound to the sensillum cuticle in vivo) and subsequently activate ORs.Using this novel bioassay we compared the ability of two different classes of soluble protein found in animals (bovine serum albumin, BSA, and mouse odorant binding protein, OBP) to dissolve corn borer pheromone from the hydrophobic membrane in comparison to its PBP. Supporting the early experiments, we found no evidence that the PBPs influence specificity of pheromone transport and activation. Contradicting results have been reported in the literature, and these results are important and impactful in helping resolve those contradictions to help move the field of study forward. In fact, our experiments suggested that PBPs might actually act as a sink for pheromone. This is interesting since recent research that knocked out an OBP from fruit flies found that sensitivity of the neuron to odors did not decrease, but actually increased somewhat, and these authors suggested OBPs may act as a form of gain control. Recent publications have reported results using new crisper technology to knock out a moth PBP and their experimentssuggested PBPs were redundant and not specific in their transport of pheromones. Collectively this research suggests the ORs are the primary molecular component controlling the responses of olfactory neurons topheromones. Here, a collaborative set of experiments with Cornell University and Penn State University produced a verysignificant result from this project. We were able to demonstrate that an aberrantresponse of an OR to a non pheromone component translated into behavioral attraction of males moths to that same component, demonstrating the direct relationship of OR response to male moth behavior.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Brad S. Coates, Erik B. Dopman, Kevin W. Wanner and Thomas W. Sappington. 2018
Genomic mechanisms of sympatric ecological and sexual divergence in a model agricultural pest, the European corn borer. Current Opinion in Insect Science
Volume 26, Pages 50-56
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Zhang T, Sun Y, Wanner KW, Coates BS, He K, Wang Z. 2017.
Binding affinity of five PBPs to Ostrinia sex pheromones. BMC Mol Biol. 2017 Feb 7;18(1):4.
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Robertson HM, Waterhouse RM, Walden KKO, Ruzzante L, Reijnders MJMF, Coates BS, Legeai F, Gress JC, Biyiklioglu S, Weaver DK, Wanner KW, Budak H. 2018. Genome Sequence of the Wheat Stem Sawfly, Cephus cinctus, Representing an Early-Branching Lineage of the Hymenoptera, Illuminates Evolution of Hymenopteran Chemoreceptors. Genome Biol Evol. 10(11):2997-3011.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2017
Citation:
Wanner, KW. 2017. Molecular mechanisms underlying the evolution of sex pheromone communication in the Ostrinia. 2017 Entomology Society of America Meeting November 5, 2017
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2014
Citation:
Wanner, KW. 2014. Insights into insect-insect communication - molecular characterization of pheromone production and detection. Entomological Society of Canada, September 30, 2014
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2014
Citation:
Wanner, KW. 2014. Elucidating the molecular mechanisms of sex pheromone detection by moths using Ostrinia as a model. IWGO: International Working Group on Ostrinia and Other Maize Pests
April, 2014
- Type:
Other
Status:
Submitted
Year Published:
2019
Citation:
Draft Manuscript: Herdlicka, Brent and Wanner, Kevin W. 2019. No Increase in Sensitivity when Ostrinia nubilalis PBP2 and PBP3 are Combined with Pheromone Receptors In Vitro. Now submitted to Insect Biochemistry and Molecular Biology, Manuscript Number: IB-D-19-00121
- Type:
Other
Status:
Other
Year Published:
2019
Citation:
Draft Manuscript: Kevin W. Wanner, Kevin Moore, Jianrong Wei, Brent C. Herdlicka, Charles E. Linn Jr. and Thomas C. Baker. 2019. Wide-field odorant receptors reveal the presence of a cryptic, redundant sex pheromone component in the European corn borer, Ostrinia nubilalis. Prepared manuscript waiting to be submitted to Journal of Chemical Ecology.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2019
Citation:
Kevin W. Wanner, Kevin Moore, Jianrong Wei, Brent C. Herdlicka, Charles E. Linn Jr. and Thomas C. Baker. 2019. A moth pheromone odorant receptor with a wide receptive field provides an open door to novel pheromone blends and speciation. 16th European Symposium for Insect Taste and Olfaction (ESITO). Sardinia, Italy.
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