De novo assembly and characterization of the skeletal muscle and electric organ transcriptomes of the African weakly electric fish Campylomormyrus compressirostris (Mormyridae, Teleostei)

African weakly electric fishes (Mormyridae) underwent an outstanding adaptive radiation (about 200 species), puta-tively owing to their ability to communicate through species-specific weak electric signals. The electric organdischarge (EOD) is produced by muscle-derived electrocytes organized in piles to form an electric organ. Despite theimportance of this trait as a prezygotic isolation mechanism, genomic resources remained limited. We present here afirst draft of the skeletal muscle and electric organ transcriptomes from the weakly electric fish species Camp-ylomormyrus compressirostris, obtained using the Illumina HiSeq2000 sequencing technology. Approximately 6.8Gbp of cDNA sequence data were produced from both tissues, resulting in 57 268 109 raw reads for the skeletal mus-cle and 46 934 923 for the electric organ, and assembled de novo into 46 143 and 89 270 contigs, respectively. About50% of both transcriptomes were annotated after protein databases search. The two transcriptomes show similarprofiles in terms of Gene Ontology categories composition. We identified several candidate genes which are likely toplay a central role in the production and evolution of the electric signal. For most of these genes, and for many otherhousekeeping genes, we were able to obtain the complete or partial coding DNA sequences (CDS), which can beused for the development of primers to be utilized in qRT-PCR experiments. We present also the complete mitochon-drial genome and compare it to those available from other weakly electric fish species. Additionally, we located 1671SSR-containing regions with their flanking sites and designed the relative primers. This study establishes a first stepin the development of genomic tools aimed at understanding the role of electric communication during speciation