Evolution of the achaete-scute complex in insects: convergent duplication of proneural genes

Proneural genes encode transcriptional activators of the basic Helix–loop–helix class that are involved in neuronal specification and differentiation. We have used the recent availability of genome sequences of multiple distant insect species to study the evolution of a family of proneural genes, the achaete-scute genes, and to examine their genomic organization and evolution. We document independent evolution of multiple copies of achaete-scute homologues and argue that this might have contributed to morphological diversity in Diptera and Lepidoptera.