Independent elaboration of steroid hormone signaling pathways in metazoans

doi:10.1073/pnas.0812138106

Independent elaboration of steroid hormone signaling pathways in metazoans

^aMolecular Zoology Team, Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1 and Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France;
^bUnité Mixte de Recherche 7221, Evolution des Régulations Endocriniennes, Muséum National d'Histoire Naturelle, 75005 Paris, France;
^cUniversité de Lyon, Université Lyon 1, F-69000 Lyon, France;
^dCentre National de la Recherche Scientifique, Unité Mixte de Recherche 5558, Laboratoire de Biométrie et Biologie Evolutive, F-69622 Villeurbanne, France;
^eUnité Mixte de Recherche 7622, Biologie du Developpement, Equipe Biogenèse des Signaux Hormonaux, Centre National de la Recherche Scientifique, Université Paris 6, 75005 Paris, France; and
^fDepartment of Medicine, University of California at San Diego, La Jolla, CA 92093-0693

Abstract

Steroid hormones regulate many physiological processes in vertebrates, nematodes, and arthropods through binding to nuclear receptors (NR), a metazoan-specific family of ligand-activated transcription factors. The main steps controlling the diversification of this family are now well-understood. In contrast, the origin and evolution of steroid ligands remain mysterious, although this is crucial for understanding the emergence of modern endocrine systems. Using a comparative genomic approach, we analyzed complete metazoan genomes to provide a comprehensive view of the evolution of major enzymatic players implicated in steroidogenesis at the whole metazoan scale. Our analysis reveals that steroidogenesis has been independently elaborated in the 3 main bilaterian lineages, and that steroidogenic cytochrome P450 enzymes descended from those that detoxify xenobiotics.

Footnotes

¹To whom correspondence should be addressed at:
Université de Lyon, Université Lyon 1, Ecole Normale Supérieure de Lyon, Institut de Génomique Fonctionnelle de Lyon, Equipe de Zoologie Moléculaire, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5242, Institut National de la Recherche Agronomique, Unité Mixte de Recherche 1237, 46 Allée d'Italie, 69364 Lyon Cedex 07, France.
E-mail: vincent.laudet{at}ens-lyon.fr
Edited by Jan-Åke Gustafsson, Karolinska Institutet, Stockholm, Sweden, and approved May 26, 2009
Author contributions: G.V.M. and V.L. designed research; G.V.M. performed research; G.V.M., R.T., and V.L. analyzed data; and G.V.M., C.D.-V., B.A.D., M.E.B., and V.L. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/cgi/content/full/0812138106/DCSupplemental.