MARCUS, JM*; MONTEIRO, A; SUNY at Buffalo: Progress in the development and evolution of lepidopteran color patterns

Butterfly wing color patterns are among the most attractive model systems for exploring the relationship between development and evolution because they are highly variable, consist of clearly defined subunits, are structurally simple and at least some patterns are clearly associated with fitness benefits associated with natural or sexual selection. For these reasons, many models for understanding butterfly color patterns have been developed. These models can be divided into two types. The first type employs generalized mechanisms of pattern formation (e.g. lateral inhibition, reaction-diffusion, diffusion gradient, and threshold responses) to make predictions about how color patterns will vary as parameters of the model are changed. The second group of models proposes regulatory interactions between specific gene products to account for the differentiation of particular color patterns. These genetic models have relied heavily on the study of expression patterns of candidate genes identified primarily from Drosophila melanogaster and with few exceptions, gene products thought to be involved in patterning the butterfly wing are implicated on the basis of a suggestive expression pattern which coincides with the shape and location of a color pattern element. Experimental manipulation of gene expression patterns within a butterfly species has proven to be difficult. Until methods are developed to permit the routine manipulation of expression patterns to test the proposed relationships between gene products it will not be possible to unify the generalized developmental models with the genetic regulatory hierarchies that have been proposed for the formation of butterfly color pattern. Here we propose a new strategy for the manipulation of gene expression in butterflies and report our preliminary results.