title: Duplications of hox gene clusters and the emergence of vertebrates.
abstract: The vertebrate body plan is characterized by an increased complexity relative to that of all other chordates and large-scale gene amplifications have been associated with key morphological innovations leading to their remarkable evolutionary success. Here, we use compound full Hox clusters deletions to investigate how Hox genes duplications may have contributed to the emergence of vertebrate-specific innovations. We show that the combined deletion of HoxA and HoxB leads to an atavistic heart phenotype, suggesting that the ancestral HoxA/B cluster was co-opted to help in diversifying the complex organ in vertebrates. Other phenotypic effects observed seem to illustrate the resurgence of ancestral (plesiomorphic) features. This indicates that the duplications of Hox clusters were associated with the recruitment or formation of novel cis-regulatory controls, which were key to the evolution of many vertebrate features and hence to the evolutionary radiation of this group.
authors.affiliation: Department of Genetics and Evolution, University of Geneva, Sciences III, Quai Ernest-Ansermet 30, 1211 Geneva 4, Switzerland.
authors.forename: Natalia
authors.initials: N
authors.lastname: Soshnikova
authors.forename: Romain
authors.initials: R
authors.lastname: Dewaele
authors.forename: Philippe
authors.initials: P
authors.lastname: Janvier
authors.forename: Robb
authors.initials: R
authors.lastname: Krumlauf
authors.forename: Denis
authors.initials: D
authors.lastname: Duboule
mesh_terms: D000818:Animals; D019521:Body Patterning / Q000235:genetics; D004622:Embryo, Mammalian / Q000196:embryology / Q000378:metabolism; D019143:Evolution, Molecular; D020440:Gene Duplication; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000145:classification / Q000235:genetics*; D017403:In Situ Hybridization; D051379:Mice; D005810:Multigene Family / Q000235:genetics*; D009154:Mutation; D010802:Phylogeny; D014714:Vertebrates / Q000196:embryology / Q000235:genetics*
chemical_list: D018398:Homeodomain Proteins