The Hirudo medicinalis (medicinal leech) transcriptome project began in 2004 as a collaborative effort between the Annelid Neuroimmunology Laboratory of Dr. Michel Salzet in Lille and the laboratories of Drs. Eduardo Macagno and William Kristan (University of California San Diego, USA), Dr. Vincent Torre (SISSA Trieste, Italy) and Dr. Bento Soares (Northwestern University, USA). The project got underway with the construction in the laboratory of Dr. Soares of a partially-normalized, multi-embryonic stage leech EST library enriched in rare transcripts. Sequencing of over 15,000 clones from his library has made it possible to identify many interesting genes, and above all to obtain the most complete representation of the leech transcriptome available at this time. An additional 20 to 30,000 clones from this library will be sequenced and annotated in the near future. Several DNA microarrays are being produced with the sequenced EST fragments in the Salzet Laboratory (UNR CNRS 8017) in collaboration with Professor Y. Lemoine.

With the goal of creating a complete and detailed catalog of the genes transcribed in each of the ~400 neurons in each segmental ganglion of the medicinal leech, Genoscope is undertaking the production of 100,000 reads from a new EST library created from the adult nervous system by the laboratory of Dr. Soares. Since most of these neurons have been characterized anatomically and functionally, this project will result in the most complete data sets relating gene expression profiles and physiological function becoming available for detailed study.