Pleiotropic function of Dlx5/6 in coordinating the development of mammalian vocal and auditory organs

Acoustic communication, essential for mammalian social interactions, involves both effector (vocal) and receptor (auditory) organs that present a wide variety of morphologies between species. The molecular mechanisms supporting the harmonious diversification of effector and receptor systems along with the evolution of species-specific acoustic communication are still poorly understood. It is conceivable that common genetic pathways determine the parallel morphogenesis of vocal and auditory systems. Here, we investigated this question by generating mutant mice with targeted invalidation of Dlx5/6 genes in the otic placode and cephalic neural crest cells, contributing to the formation of the ear and vocal tract components. We show that Dlx5/6 inactivation provokes simultaneous defects of the outer, middle and inner ear and of the jaw, pharynx and larynx musculoskeletal systems. Our findings support the notion that Dlx5/6 genes played a pleiotropic role in the co-adaptation of vocal and auditory systems in mammals.