title: Evolution of the Sox gene family within the chordate phylum.
abstract: The ancient Sox gene family is a group of related transcription factors that perform a number of essential functions during embryonic development. During evolution, this family has undergone considerable expansion, particularly within the vertebrate lineage. In vertebrates SOX proteins are required for the specification, development and/or morphogenesis of most vertebrate innovations. Tunicates and lancelets are evolutionarily positioned as the closest invertebrate relatives to the vertebrate group. By identifying their Sox gene complement we can begin to reconstruct the gene set of the last common chordate ancestor before the split into invertebrates and vertebrate groups. We have identified core SOX family members from the genomes of six invertebrate chordates. Using phylogenetic analysis we determined their evolutionary relationships. We propose that the last common ancestor of chordates had at least seven Sox genes, including the core suite of SoxB, C, D, E and F as well as SoxH.
authors.affiliation: Developmental Biology and Genomics Laboratory, Department of Anatomy, Otago School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
authors.forename: Phoebe
authors.initials: P
authors.lastname: Heenan
authors.affiliation: Developmental Biology and Genomics Laboratory, Department of Anatomy, Otago School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
authors.forename: Lisa
authors.initials: L
authors.lastname: Zondag
authors.affiliation: Developmental Biology and Genomics Laboratory, Department of Anatomy, Otago School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand. Electronic address: meganj.wilson@otago.ac.nz.
authors.forename: Megan J
authors.initials: MJ
authors.lastname: Wilson
mesh_terms: D000818:Animals; D001483:Base Sequence; D043344:Chordata / Q000145:classification* / Q000235:genetics / Q000378:metabolism*; D017124:Conserved Sequence; D019143:Evolution, Molecular; D007448:Invertebrates / Q000235:genetics / Q000378:metabolism; D005810:Multigene Family; D010802:Phylogeny; D055747:SOX Transcription Factors / Q000235:genetics*; D014714:Vertebrates / Q000235:genetics / Q000378:metabolism
chemical_list: D055747:SOX Transcription Factors
keywords: Chordate; Development; Evolution; Lancelet; Sox genes; Tunicate; Vertebrate