Cloning, characterization, and comparative activity of turbot IGF-I and IGF-II

International audienceIGF peptides belong to a complex system that is known to play a major role in the control of growth and development in mammals. Even if studies performed in nonmammalian species tend to demonstrate an important function of these molecules, use of heterologous ligands, especially in fish, partly limit our knowledge of the physiological role(s) of IGFs. We report in this study the cloning, production, and characterization in an evolved fish, the turbot Psetta maxima, of mature IGF-I and IGF-II. The deduced 68-amino-acid IGF-I and 70-amino-acid IGF-II show 75% and 74% sequence identity with their mammalian counterparts, respectively, confirming the high sequence homology observed in other species. The development of a simple and efficient system for the production and purification of both IGF-I and IGF-II in Escherichia coli was used to investigate the in vitro regulation of GH release in the turbot. Our results demonstrated for the first time in a Euteleost species that both peptides specifically inhibited GH release. Both hormones were equally potent in inhibiting GH release from dispersed pituitary cells, with maximal inhibitory effects of 92% and 91% at 1 nM doses after 12 days of culture, respectively. The biologically active recombinant turbot IGFs that we obtained will allow us to further investigate potential and perhaps the specific role(s) of these hormones in turbot as, in contrast with mammals, growth in fish is potentially continued during “adult” life

Report on the second season (2009) of the Madâ'in Sâlih Archaeological Project

This volume is the report on the results of the second excavation season, 2009, of the Saudi-French Archaeological Project at Madâ'in Sâlih, Nabataean Hegra in northwest Saudi Arabia (MAEE, SCTA, CNRS, Univ Paris 1, IFPO). Apart from the results obtained in the different excavation areas (both in the residential area, in the monumental tomb IGN 117 and in various areas south of the Jabal Ithlib), the reader will find reports on the archaeobotanical remains (Ch. Bouchaud), on the pottery (C. Durand et Y. Gerber) and on the restoration of Area 7Ce volume constitue le rapport sur les résultats de la deuxième campagne de fouilles (2009) de la Mission archéologique franco-saoudienne de Madâ'in Sâlih, l'ancienne Hégra des Nabatéens, dans le nord-ouest de l'Arabie Saoudite (MAEE, SCTA, CNRS, Univ. Paris 1, IFPO). Outre les résultats obtenus dans les différents chantiers (dans la zone résidentielle, dans le tombeau monumental IGN 117 et dans différents secteurs au sud du Jabal Ithlib), le lecteur trouvera des rapports sur les macro-restes végétaux (Ch. Bouchaud), la céramique (C. Durand et Y. Gerber) et la restauration de la Zone