Animal farm: regulatory alterations and the morphological evolution of the limb

Abstract

Recent efforts in mapping the regulatory genome have uncovered that loci with essential functions in development typically contain complex cis-regulatory landscapes. Such complexity is required to achieve precise spatio-temporal control of gene expression, as developmental genes are frequently required in several tissues and time points. A general concept in the field is that alterations in the regulation of these pleiotropic and conserved developmental genes are a main mechanism underlying the evolution of morphology. The limb skeleton is an ideal system to identify the mechanisms that participated in the appearance of anatomical novelties, as it has greatly diversified in tetrapods as adaptation to different modes of life and locomotion (flying, running, swimming, burrowing, etc.). In our lab we combine the strengths of mouse genetics with the use of functional genomics tools in large mammals such as cow and pig to identify regulatory alterations that may have played a role in the acquisition of the highly specialized limb morphologies present in these artiodactyls.