From Nature to the Lab: Establishing Drosophila Resources for Evolutionary Genetics

Abstract

In recent years important tools have been developed in Drosophila to capture with the greatest possible accuracy the variation found in nature. Efforts, such as the Drosophila melanogaster Genetic Reference Panel (DGRP) or the Drosophila Synthetic Population Resource (DSPR) allied to the advances in whole-genome sequencing and analysis have propelled to unprecedented level our capacity to dissect the genotype-phenotype map. However, several practical problems arise upstream of these analyses starting with the collection and identification of wild specimens. These problems are dealt with in different ways by each researcher generating solutions not necessarily compatible across laboratories. Here, we provide a systematic coverage of every phase of this process based on our experience, and suggest procedures to maximize and share the generated resources potentiating future applications. We propose a detailed pipeline to guide researchers from collection in the wild to the development of a large array of molecular and genetic resources. We designed a multiplex-PCR that distinguishes sister species D. melanogaster and D. simulans and is diagnostic of the presence/absence of Wolbachia infection. These procedures may extend to other cryptic species pairs and endosymbionts. We developed a standardized protocol to create, replicate and maintain isofemale lines and outbred populations. Finally, we explore the potential of outbred populations across several applications from experimental evolution, to introgression of transgenic constructs or mutant alleles, and genomic analyses. We hope to contribute to the success in developing Drosophila resources for evolutionary genetics studies and facilitate exchanges across laboratories based on a common set of procedures.

Creating outbred and inbred populations in haplodiploids to measure adaptive responses in the laboratory

“…To ensure that data obtained in the laboratory reflect the range of possible responses found in natural populations of the species under study, the ancestral population should reflect the variability found in the field (Faria & Sucena, 2017;MacDonald & Long, 2004;Nunes et al, 2008). Several studies have used laboratory populations founded by a large number of individuals collected in the field and maintained at high numbers in the laboratory (e.g., Magalhães, Fayard, Janssen, Carbonell, & Olivieri, 2007;Martins, Faria, Teixeira, Magalhães, & Sucena, 2013;Mery & Kawecki, 2002;Teotónio, Chelo, Bradić, Rose, & Long, 2009).…”

Transgenerational effects in offspring of chronically irradiated populations of Drosophila melanogaster after the Chernobyl accident

“…Twenty‐five pairs of specimens were placed in separate tubes. This procedure was repeated until generation 20 to obtain full‐sibs; isofemale strains become genetically homogeneous (isogenic) after 20 generations of full‐sibs (Faria and Sucena 2017). The obtained isogenic strains (25 strains) were maintained for several experimental generations (EGs).…”

Phenotype-dependent habitat choice is too weak to cause assortative mating between Drosophila melanogaster strains differing in light sensitivity

“…We used outbred (genetically variable) populations of wild type and white (w 1118 ) D. melanogaster [43]. All the stocks were reared on conventional wheat flour and agar medium under a 12h/12h light-dark cycle at 25 °C.…”