Quand Tribolium complémente la génétique de la drosophile

Abstract

Le genome de Tribolium castaneum, publie recemment, ne serait-il qu’une goutte de plus versee dans l’ocean genomique ? Non, car Tribolium se distingue a plus d’un titre. D’abord, en tant que coleoptere, il represente un ordre qui compte environ le quart des especes animales. De plus, cet insecte omnivore est un nuisible pour les grains et les farines du monde entier. Enfin, Tribolium est discretement entre dans l’elite des organismes modeles de la genetique. Cet article vise a montrer que Tribolium est un compagnon de laboratoire complementaire de la drosophile, notamment pour la genetique du developpement.

With its recently sequenced genome, the red flour beetle Tribolium castaneum became one of the few model organisms with all the main genetic tools. As a coleoptera, it belongs to the most species-rich order of animals. Tribolium is also a worldwide pest for stored dried foods. Regarding developmental biology, Tribolium offers a complementary model to the highly derived Drosophila. For example, the function of many gap and pair-rule segmentation genes is different in both species. These differences reveal the evolutionary plasticity between two modes of development, with a long germ band in fly and a short one in Tribolium. This beetle allowed the identification of a new type of ecdysone receptor for holometabolous insects. Finally, in the search for the juvenile hormone receptor, a crucial result was obtained with experiments that could be performed only with Tribolium, and not with Drosophila. Tribolium, in association with Drosophila, should help to understand the general rules of development in insects.