Project description:Aposematic color pattern mimicry in Heliconius butterflies provides a well-known example of adaptation via selection on a few genes of large effect. To understand how selection at individual genes can drive the evolution of complex traits, we functionally characterized five novel enhancers of the color pattern gene, optix. In Heliconius erato we found that wing pattern enhancers are largely ancestral, pleiotropic, functionally interdependent, and introgressed between populations. Remarkably, many of these enhancers are also associated with regional pattern variation in the distantly related co-mimics Heliconius melpomene and Heliconius timareta. Our findings provide a case study of how parallel co-evolution of ancient, multifunctional regulatory elements can facilitate the rapid diversification of complex phenotypes, and provide a counterpoint to many widespread assumptions of cis-regulatory evolution.
Project description:Aposematic color pattern mimicry in Heliconius butterflies provides a well-known example of adaptation via selection on a few genes of large effect. To understand how selection at individual genes can drive the evolution of complex traits, we functionally characterized five novel enhancers of the color pattern gene, optix. In Heliconius erato we found that wing pattern enhancers are largely ancestral, pleiotropic, functionally interdependent, and introgressed between populations. Remarkably, many of these enhancers are also associated with regional pattern variation in the distantly related co-mimics Heliconius melpomene and Heliconius timareta. Our findings provide a case study of how parallel co-evolution of ancient, multifunctional regulatory elements can facilitate the rapid diversification of complex phenotypes, and provide a counterpoint to many widespread assumptions of cis-regulatory evolution.
Project description:Genomic studies of phylogeny, population structure, genetic diversity, speciation, gene flow, demography and selection in Heliconius butterflies.
Project description:Aposematic color pattern mimicry in Heliconius butterflies provides a well-known example of adaptation via selection on a few genes of large effect. To understand how selection at individual genes can drive the evolution of complex traits, we functionally characterized five novel enhancers of the color pattern gene, optix. In Heliconius erato we found that wing pattern enhancers are largely ancestral, pleiotropic, functionally interdependent, and introgressed between populations. Remarkably, many of these enhancers are also associated with regional pattern variation in the distantly related co-mimics Heliconius melpomene and Heliconius timareta. Our findings provide a case study of how parallel co-evolution of ancient, multifunctional regulatory elements can facilitate the rapid diversification of complex phenotypes, and provide a counterpoint to many widespread assumptions of cis-regulatory evolution.
Project description:We investigated gene expression levels in Heliconius erato butterflies with divergent wing patterns across a 656KB genomic interval linked to the red color pattern wing polymorphism. This included comparison of expression between two H. erato color pattern populations (H. e. petiverana and a H.e. etylus x H. himera hybrid) across three sections of the forewing that differed in pigmentation (the basal, mid, and distal wing sections) and five different stages of pupal development (Day 1, 3, 5 pupae and ommochrome and melanin pigmentation stages). These results allowed us to determine whether certain genes in this interval were differentially expressed between the wing pattern elements, and, therefore, potentially responsible for adaptive color pattern variation in these butterflies.
Project description:The purpose of this experiment was to compare RNA-seq profiles of adult male and female butterfly chemosensory tissues to identify tissue- and sex-specific differences in gustatory and olfactory gene expression. Three biological replicates per sex were produced from individual Heliconius melpomene rosina butterflies. For the antennal libraries, both antennae were used, for the labial palps + proboscis libraries both labial palps and each proboscis was used, and for the leg libraries all six legs were used.
