Analysis of polycerate mutants reveals the evolutionary co-option of HOXD1 for horn patterning in Bovidae
Allais-Bonnet, Aurelie; Hintermann, Aurelie; Deloche, Marie-Christine; Cornette, Raphael; Bardou, Philippe; Naval-Sanchez, Marina; Pinton, Alain; Haruda, Ashleigh; Grohs, Cecile; Zakany, Jozsef; Bigi, Daniele; Medugorac, Ivica; Putelat, Olivier; Greyvenstein, Ockert; Hadfield, Tracy; Jemaa, Slim Ben; Bunevski, Gjoko; Menzi, Fiona; Hirter, Nathalie; Paris, Julia M.; Hedges, John; Palhiere, Isabelle; Rupp, Rachel; Lenstra, Johannes A.; Gidney, Louisa; Lesur, Josephine; Schafberg, Renate; Stache, Michael; Wandhammer, Marie-Dominique; Arbogast, Rose-Marie; Guintard, Claude; Blin, Amandine; Boukadiri, Abdelhak; Riviere, Julie; Esquerre, Diane; Donnadieu, Cecile; Danchin-Burge, Coralie; Reich, Coralie M.; Riley, David G.; Van Marle-Koster, Este; Cockett, Noelle; Hayes, Benjamin J.; Drogemuller, Cord; Kijas, James; Pailhoux, Eric; Tosser-Klopp, Gwenola; Duboule, Denis; Capitan, Aurelien
Date:
2021-06
Abstract:
In the course of evolution, pecorans (i.e., higher ruminants) developed a remarkable diversity of osseous cranial appendages,
collectively referred to as “headgear,” which likely share the same origin and genetic basis. However, the nature
and function of the genetic determinants underlying their number and position remain elusive. Jacob and other rare
populations of sheep and goats are characterized by polyceraty, the presence of more than two horns. Here, we characterize
distinct POLYCERATE alleles in each species, both associated with defective HOXD1 function. We show that
haploinsufficiency at this locus results in the splitting of horn bud primordia, likely following the abnormal extension of
an initial morphogenetic field. These results highlight the key role played by this gene in headgear patterning and
illustrate the evolutionary co-option of a gene involved in the early development of bilateria to properly fix the position
and number of these distinctive organs of Bovidae.
