title: Protein evolution of ANTP and PRD homeobox genes.
abstract: BACKGROUND
  Although homeobox genes have been the subject of many studies, little is known about the main amino acid changes that occurred early in the evolution of genes belonging to different classes.
  
  
  RESULTS
  In this study, we report a method for the fast and efficient retrieval of sequences belonging to the ANTP (HOXL and NKL) and PRD classes. Furthermore, we look for diagnostic amino acid residues that can be used to distinguish HOXL, NKL and PRD genes.
  
  
  CONCLUSIONS
  The reported protein features will facilitate the robust classification of homeobox genes from newly sequenced bilaterian genomes. Nevertheless, in non-bilaterian genomes our findings must be cautiously applied. In principle, as long as a good manually curated data set is available the approach here described can be applied to non-bilaterian organisms as well. Our results help focus experimental studies onto investigating the biochemical functions of key homeodomain residues in different gene classes.
authors.affiliation: Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal. nf@ibmc.up.pt
authors.forename: Nuno A
authors.initials: NA
authors.lastname: Fonseca
authors.forename: Cristina P
authors.initials: CP
authors.lastname: Vieira
authors.forename: Peter W H
authors.initials: PW
authors.lastname: Holland
authors.forename: Jorge
authors.initials: J
authors.lastname: Vieira
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D051943:Antennapedia Homeodomain Protein / Q000737:chemistry / Q000235:genetics*; D016384:Consensus Sequence; D019143:Evolution, Molecular; D005801:Genes, Homeobox / Q000235:genetics*; D018398:Homeodomain Proteins / Q000737:chemistry / Q000235:genetics; D006801:Humans; D009419:Nerve Tissue Proteins / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D051943:Antennapedia Homeodomain Protein; D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins