Fine-Scale Genetic Mapping and Sequence Analysis of Genes Involved in Honey Bee Stinging Behavior

Purdue University, West Lafayette IN

Investigators

Abstract

Fine-scale mapping and genetic analysis of genes involved in honey bee stinging behavior. ABSTRACT The genetic architecture (numbers of genes and their effects) of behavioral traits is an important consideration for the field of behavioral ecology, yet little is known on this topic. The honey bee may be useful in this regard because it is becoming recognized as a model organism for behavioral and behavioral genetic studies. As a behavioral genetic model, the bee has the advantages of ease of culture, social behavior, haploid males, and the highest recombination rate ever reported for a metazoan. The high meiotic recombination rate facilitates the construction of detailed genetic maps and cloning genes based on their positions on genetic maps because genetic distance is directly related to crossover rates. The proposed project seeks to study the role of specific genes and pheromonal communication in honey bee defensive behavior. Previous studies identified and mapped quantitative trait loci (QTL) that mark the positions of genes that influence a colony-level behavioral trait, the numbers of stings that bees deposited in a behavioral assay. QTL that influence alarm pheromone production were also identified. Two of the "stinging" QTL were subsequently found to influence the guarding and stinging behavior of individual bees, thus confirming the QTL effects on behavior. One of the two confirmed QTL also may have an influence on alarm pheromone production. A QTL that influences levels of an unknown alarm pheromone component that correlated with colony stinging response mapped close to this defensive-behavior QTL. The proposed research would further characterize QTL effects on individual and colony behavioral phenotypes and seek to identify specific components of behavior that are influenced by each gene. In addition, crosses with haploid males would allow for further genetic dissection to pinpoint the location of genes more precisely and ultimately obtain the sequence of these genes. These crosses would generate lines of bees, each of which is descended from a different haploid male. The haploid fathers will differ from each other in key regions near the QTL. The next step in the proposed research is to identify large bacterial artificial chromosome (BAC) clones of honey bee DNA that span the region containing the QTL. For example, if the gene influencing the behavioral trait can be pinpointed to 5 centimorgans of genetic distance, this represents about 250 kilobases (Kb) of honey bee DNA. This 250 Kb region can be spanned by just a few BAC clones because the current honey bee BAC library has average clone sizes of 113 Kb. Sequencing and bio-informatic analyses would then be used to identify candidate genes for these QTL.