Genetic polymorphisms underlying feeding preferences in blow flies

• Grant number: 23/12670-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: November 01, 2023
• End date: October 31, 2025
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Agreement: NSF - Dimensions of Biodiversity and BIOTA
• Principal Investigator: Tatiana Teixeira Torres
• Grantee: Kelly da Silva e Souza
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 20/05636-4 - Dimensions US-BIOTA-São Paulo: more to the blow fly than meets the eye: understanding evolutionary and genetic origins of diverse trophic specializations, AP.BTA.TEM

Abstract

Possible origins of the different habits in Calliphoridae are unknown, but it has been proposed that the extant feeding preferences reflect the progressive evolution of parasitism in Calliphoridae. The ability of some species to survive on different substrates is particularly interesting and allows us to analyze, on an intraspecific scale, the components potentially involved in the evolution of parasitism. Lucilia cuprina is a facultative parasite, as it can colonize and develop on decomposing material as well as live tissues, inducing myiasis, mainly in sheep. One untested hypothesis is that subspecies of L. cuprina may have different lifestyles; L. cuprina dorsalis would be more parasitic than L. cuprina cuprina. Both sub-species are found in Australia and Southern Africa where flystrike in sheep occurs. On the other hand, L. cuprina cuprina is believed to be the only subspecies present in the New World, where it is not considered a parasite. In this project, this hypothesis will be explored to identify genes underlying oviposition/feeding preference using two different approaches: 1) population genomics; and 2) artificial selection of populations on contrasting diets. We will sequence genomes of both subspecies from naturally occurring populations, to conduct a genome-wide variant analysis and identify the genes and genomic regions associated with diverse habits. Artificial selection followed by sequencing ("Evolve and Resequence" or E&R) will also be used to investigate the facultative habit of L. cuprina. This strategy permits polymorphisms associated with the conditions tested to be identified. We will create strains of L. cuprina cuprina that will develop (and evolve), over several generations (20-30), in a decomposing or fresh substrate. The selecte strains will be used to analyze patterns of gene expression and selection signals in the genome. (AU)