Deciphering Pleiotropic Effects: A Molecular Characterisation of the Foraging Gene in Drosophila melanogaster

Pleiotropy is defined as the manifold effects of a gene at the phenotypic level. Understanding the mechanisms of manifold gene action has important implications for many fields of biology ranging from evolution and to medicine. The foraging gene, in Drosophila melanogaster, has long been a pivotal example of a single gene with natural variants that affect feeding-related phenotypes. One possible mode of action for foraging’s pleiotropy is through independent regulation of its gene products. Characterization of the foraging gene revealed 4 distinct promoters that produce 21 transcripts, and 9 ORFs. A foraging null mutant of the locus was generated using Ends-out gene targetting. foraging null mutants had reduced foraging behaviour, reduced food intake behaviour, and increased lipid levels. A recombineered full genomic rescue of the gene rescued the effects of the null mutation. By comparing the effects of the null mutant with those of the natural variants, I showed that these feeding-related phenotypes were differentially regulated. A promoter manipulation strategy identified diverse, and non-overlapping expression patterns associated with the 4 foraging promoters. Expression was seen in the nervous and gastric systems of the larva and adult fly, as well as the reproductive systems of adult fly. This expression suggests potential new roles for the foraging gene in the larva and adult fly. Characterizing the regulation of foraging's gene products will further our understanding of its role in behaviour, and shed light on the evolutionary origins of natural variants of the foraging. Not only will this study further our understanding of this gene's conserved function across taxa, but it will also help elucidate the role for differential transcriptional regulation in achieving multiple functions of a gene. This could further serve as fodder for investigations intro the roles of neo-functionalization versus escape from adaptive constraint.

Department dc:contributor.department

Cell and Systems Biology

Year dc:date.issued

2016

Author dc:creator

• Allen, Aaron Munro

Advisor dc:contributor.advisor

• Sokolowski, Marla B

Handle dc:identifier.uri

http://hdl.handle.net/1807/88980

OAI identifier oai:identifier

oai:utoronto.scholaris.ca:1807/88980