The evolution of Hox gene regulation in vertebrates

Hox genes encode for transcription factors that play a fundamental role in anterior-posterior patterning and are remarkably conserved throughout evolution. They are tightly regulated by a number of molecules including histone-modifying protein complexes that change transcriptional states of Hox genes and maintain their expression spatially restricted . Since only a few differences in Hox gene number have been observed between mammals and other vertebrates, the rich morphological diversity that exists in vertebrates may be explained by differences in Hox gene regulation.

When compared to other vertebrates, Squamata species were shown to have larger Hox clusters due to an increased amount of repeats in their intronic and intergenic regions. This fact suggests that the excess repeats could have altered the epigenetic regulation of Hox genes, ultimately affecting the Squamata body plan evolution.

Our aim is to describe the epigenetic marks found in corn snake embryos and compare them with the previously obtained epigenetic data described in the developing mouse embryo.