title: Molecular evolution of the androgenic hormone in terrestrial isopods.
abstract: In crustaceans, the androgenic gland (AG), thanks to the synthesis of the androgenic gland hormone (AGH), controls the differentiation of the primary and secondary male sexual characters. In this study, we amplified 12 new AGH cDNAs in species belonging to five different families of the infra-order Ligiamorpha of terrestrial isopods. Putative essential amino acids for the production of a functional AGH protein exhibit signatures of negative selection and are strictly conserved including typical proteolytic cleavage motifs, a putative N-linked glycosylation motif on the A chains and the eight Cys positions. An insulin-like growth factor motif was also identified in Armadillidium AGH sequences. The phylogenetic relationships of AGH sequences allowed one to distinguish two main clades, corresponding to members of the Armadillidiidae and the Porcellionidae families which are congruent with the narrow specificity of AG heterospecific grafting. An in-depth understanding of the regulation of AGH expression would help deciphering the interaction between Wolbachia, widespread feminizing endosymbiotic bacteria in isopods, and the sex differentiation of their hosts.
authors.affiliation: UMR CNRS 7267, Écologie et Biologie des Interaction (EBI), Équipe Écologie, Évolution, Symbiose (EES), Université de Poitiers, 40 avenue du Recteur Pineau, F-86022 Poitiers cedex, France. Electronic address: nicolas.cerveau@geo.uni-goettingen.de.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Cerveau
authors.affiliation: UMR CNRS 7267, Écologie et Biologie des Interaction (EBI), Équipe Écologie, Évolution, Symbiose (EES), Université de Poitiers, 40 avenue du Recteur Pineau, F-86022 Poitiers cedex, France. Electronic address: didier.bouchon@univ-poitiers.fr.
authors.forename: Didier
authors.initials: D
authors.lastname: Bouchon
authors.affiliation: Laboratoire Signalisation et Transports Ioniques Membranaires (STIM)-ERL 7368, Université de Poitiers, Pôle Biologie Santé, 1 rue Georges Bonnet, F-86022 Poitiers cedex, France. Electronic address: thierry.berges@univ-poitiers.fr.
authors.forename: Thierry
authors.initials: T
authors.lastname: Bergès
authors.affiliation: UMR CNRS 7267, Écologie et Biologie des Interaction (EBI), Équipe Écologie, Évolution, Symbiose (EES), Université de Poitiers, 40 avenue du Recteur Pineau, F-86022 Poitiers cedex, France. Electronic address: pierre.greve@univ-poitiers.fr.
authors.forename: Pierre
authors.initials: P
authors.lastname: Grève
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D060829:Arthropod Proteins / Q000737:chemistry / Q000235:genetics*; D019143:Evolution, Molecular; D042341:Gonadal Hormones / Q000737:chemistry / Q000235:genetics*; D033321:Isopoda / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D020539:Sequence Analysis, Protein; D012733:Sex Differentiation / Q000235:genetics
chemical_list: D060829:Arthropod Proteins; D042341:Gonadal Hormones
keywords: Androgenic gland; Androgenic hormone; Crustacean; Isopod; Male differentiation