The International " Bombyx plus " project entails the complete sequencing of the silkworm, Bombyx mori (to be finished in 2004) and the partial sequencing of other lepidopterans. In this concerted program, sequencing of a series of selected BACs from the noctuids Helicoverpa armigera and Spodoptera frugiperda has been planned in order to :

• evaluate the level of microsynteny between these two genomes and that of Bombyx (for validation of Bombyx as a model species);
• compare the structure of the regulatory regions of lepidopteran genes (analysis of genetic expression in invertebrates);
• obtain the sequence of genes of agronomic and biomedical interest in the selected BACs;
• extend the identification of new genes (about 40% of the sequences of Bombyx have no homologs in the Diptera).

For this project, Genoscope is undertaking the sequencing of 60 BACs each from the noctuids Helicoverpa armigera and Spodoptera frugiperda. Each BAC will be sub-cloned (5 kb inserts in pcdna2.1), followed by shotgun sequencing at 10x coverage and a finishing step.