RT Journal Article T1 Unexpectedly large number of conserved noncoding regions within the ancestral chordate Hox cluster A1 Pascual-Anaya, Juan A1 D'Aniello, Salvatore A1 Garcia-Fernàndez, Jordi K1 Genética evolutiva AB The single amphioxus Hox cluster contains 15 genes and may well resemble the ancestral chordate Hox cluster. We have sequenced the Hox genomic complement of the European amphioxus Branchiostoma lanceolatum and compared it to the American species, Branchiostoma floridae, by phylogenetic footprinting to gain insights into the evolution of Hox gene regulation in chordates. We found that Hox intergenic regions are largely conserved between the two amphioxus species, especially in the case of genes located at the 3′ of the cluster, a trend previously observed in vertebrates. We further compared the amphioxus Hox cluster with the human HoxA, HoxB, HoxC, and HoxD clusters, finding several conserved noncoding regions, both in intergenic and intronic regions. This suggests that the regulation of Hox genes is highly conserved across chordates, consistent with the similar Hox expression patterns in vertebrates and amphioxus. PB Springer YR 2008 FD 2008 LK https://hdl.handle.net/10630/33153 UL https://hdl.handle.net/10630/33153 LA eng NO Pascual-Anaya, J., D’Aniello, S. & Garcia-Fernàndez, J. Unexpectedly large number of conserved noncoding regions within the ancestral chordate Hox cluster. Dev Genes Evol 218, 591–597 (2008). https://doi.org/10.1007/s00427-008-0246-8 NO This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: http://dx.doi.org/10.1007/s00427-008-0246-8 NO Ministerio de Educación y Ciencia, proyecto BFU2005-00252 DS RIUMA. Repositorio Institucional de la Universidad de Málaga RD 20 ene 2026