Patterns of Genetic Regulation of Cuticular Hydrocarbons in Two Phylogenetically Distinct Drosophila Species: conserved mechanisms of ecological adaptation and sexual signalling

Mr Brad Foley (2008). Patterns of Genetic Regulation of Cuticular Hydrocarbons in Two Phylogenetically Distinct Drosophila Species: conserved mechanisms of ecological adaptation and sexual signalling PhD Thesis, School of Integrative Biology, The University of Queensland.

       
Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
n40207935_phd_totalthesis.pdf n40207935_phd_totalthesis.pdf application/pdf 1.49MB 0
Author Mr Brad Foley
Thesis Title Patterns of Genetic Regulation of Cuticular Hydrocarbons in Two Phylogenetically Distinct Drosophila Species: conserved mechanisms of ecological adaptation and sexual signalling
School, Centre or Institute School of Integrative Biology
Institution The University of Queensland
Publication date 2008-01-01
Thesis type PhD Thesis
Supervisor Mark Blows
Stephen Chenoweth
Ary Hoffmann
Total pages 146
Total black and white pages 146
Subjects 270000 Biological Sciences
Formatted abstract
Cuticular Hydrocarbons (CHCs) are compounds known to be important for both ecological
adaptation and sexual selection in insects, and in many species of Drosophila the evolution of CHC
expression has been shown to have an important role in the evolution of reproductive isolation
between groups. It is important to understand patterns of variation of within-species and the withinpopulation
genetics of CHC expression in order to understand the evolution of the response to
selection which leads to speciation. I have mapped Quantitative Trait Loci (QTL) of naturally
occurring variation in Recombinant Inbred Lines (RILs) in two phylogenetically distinct species of
Drosophila. In D. serrata, I created two independent panels of RILs by crossing individuals from
regions with different patterns of mate choice due to CHCs. Both panels showed very similar
patterns of variation in CHCs. Much of this variation was relevant to previously established
patterns of Reproductive Character Displacement (RCD) in this species, and replicated both field
and laboratory patterns of evolution. Females chose between males due to this variation in a
manner consistent with their population of origin, confirming I had captured genetic variation
relevant to assortative mating in this species. A major segregating factor, possibly relevant to
climatic adaptation, explained the majority of genetic variation in these RILs and interactions
between this factor and other loci likely define the RCD phenotype. Strikingly, the majority of
CHC variation directly related to RCD and mate choice in D. serrata mapped to the region
containing D. serrata homologues of D. melanogaster desat1 and 2 which controls reproductive
isolation between races of this species, suggesting the same genes may be involved in the evolution
of species across much of Drosophila. In both D. melanogaster and D. serrata, much of the
genetics of CHC expression was sex-specific, and conformed to previously shown patterns of
genomic distribution in Drosophila. Males have regions with regulatory effects of CHC expression
throughout their genome, with stronger X linkage, while female CHC expression loci are largely
localised to the chromosomal arm 3R. The D. serrata RILs will be useful tools to help understand
evolution of CHCs due to natural and sexual selection in this species.

 
Citation counts: Google Scholar Search Google Scholar
Created: Tue, 23 Sep 2008, 15:20:56 EST by Mr Brad Foley on behalf of School of Communication and Arts