Meeting Abstract
49.3 Monday, Jan. 5 A Radiation Hybrid map of the genome of Nile tilapia (Oreochromis niloticus) RAKOTOMANGA, M; AZZOUZI, N; SENGER, F; GUYON, R; HITTE, C; BAROILLER, JF; D COTTA, H; OZOUF-COSTAZ, C; GALIBERT, F*; CNRS UMR6061, Universite de Rennes 1, Rennes, France ; CNRS UMR6061, Universite de Rennes 1, Rennes, France ; CNRS UMR6026,Universite de Rennes 1, Rennes, France ; CNRS UMR6061, Universite de Rennes 1, Rennes, France ; CNRS UMR6061, Universite de Rennes 1, Rennes, France ; CIRAD-EMVT, UPR20 Montpellier France; CIRAD-EMVT, UPR20 Montpellier France; CNRS UMR7138, MNHN, Paris, France; CNRS UMR6061, Universite de Rennes 1, Rennes, France francis.galibert@univ-rennes1.fr
Radiation hybrid (RH) maps are powerful tools to guide sequence assembly of deep whole genome shotgun. In the context of the whole genome sequencing program of Nile tilapia (Oreochromis niloticus) we have undertaken the construction of a dense RH map. Splenocytes were recovered from fishes of the clonal line established by Dave Penman (Stirling University). and used for the sequencing program. They were irradiated at 3500 rads, fused to carrier hamster cells (CHO HPRT-) and cultivated in HAT selective medium. DNA was extracted from each individually cultured hybrid cell clone and the presence of tilapia DNA checked by PCR amplification of a specific repetitive DNA marker. To select the best hybrid cell lines, the DNA of the 414 independent hybrid clones was further tested for the presence of 48 microsatellite markers distributed all over the tilapia linkage map. A total of 1500 markers corresponding to genes with orthologs in the stickleback, sea bream and sea bass genomes have been designed and their distribution within the tilapia RH panel is presently underway. Construction of the RH map based on the Travelling Salesman Problem (TSP) approach will follow shortly. We will report on the main aspect of this RH map as well as on the synteny relationship unveiled by the mapping of markers for which the positions of ortholog genes on other fish genomes are known. We also like to emphasize on the need of similar dense RH maps for the other three cichlids for which a 2X sequencing effort is planed.
