title: Chromosomal location, exon/intron organization and evolution of lipocalin genes.
abstract: Lipocalins exhibit low sequence similarity that contrasts with a tightly conserved folding shared by all members of this superfamily. This conserved folding can be, at least partly, accounted for by a highly conserved gene structure. The array of lipocalin genes that have so far been studied mostly in mammals indicate a large conservation of a typical seven exon/six intron arrangement. Other conserved features include a partly coding exon 1 of variable size, fixed sizes of exons 2-5 that code for an array of lipocalin-specific beta-strands and a tendency of the last exons to either fuse or expand into further exons without major changes in the length of the resulting open reading frame. The conserved exon/intron arrangement as well as a clustering of most lipocalin genes in given chromosomes of human and mouse indicate that the lipocalin genes diverged from a shared ancestor by successive rounds of duplications followed by late changes in exon arrangements.
authors.affiliation: INSERM Unit-519 and Institut Fédératif de Recherches Multidisciplinaires sur les Peptides, Faculté de Médecine-Pharmacie, 22 Bvd Gambetta, 76183 Rouen Cedex, France. jean-philippe.salier@univ-rouen.fr
authors.forename: J P
authors.initials: JP
authors.lastname: Salier
mesh_terms: D000209:Acute-Phase Proteins; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics*; D002874:Chromosome Mapping; D019143:Evolution, Molecular; D005091:Exons; D016678:Genome; D000071816:Glycodelin; D006023:Glycoproteins; D006801:Humans; D000071068:Lipocalin-2; D054834:Lipocalins; D015513:Oncogene Proteins; D010944:Plants; D011257:Pregnancy Proteins / Q000235:genetics; D011506:Proteins / Q000235:genetics*; D011518:Proto-Oncogene Proteins
chemical_list: D000209:Acute-Phase Proteins; D002352:Carrier Proteins; D000071816:Glycodelin; D006023:Glycoproteins; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D015513:Oncogene Proteins; C045246:PAEP protein, human; C489047:Paep protein, mouse; D011257:Pregnancy Proteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; C035737:major urinary proteins