Aphids possess a double destructive ability: wounding and weakening of plants by puncture to obtain the sap, and transmission of viral diseases. This is due to their mode of reproduction (alternating parthenogenesis/sexual reproduction), trophic adaptation (host range, obligatory bacterial endosymbiosis) and vectoring of viruses (passage into the digestive tube and salivary glands). This project aims to identify the genes which regulate these processes in a single species the pea aphid (A. pisum), using a large-scale transcriptomic approach.

Genoscope will undertake the sequencing of about 35,000 ESTs from libraries from different organs of the pea aphid:

• Head (perception of photoperiodism which regulates the mode of reproduction): 10,000 ESTs
• Antenna (perception of the host): 5,000 ESTs
• Salivary glands, digestive tubes and the bacteriome (tissue that is a mixture of endosymbiotic bacteria/aphid) (trophic adaptation): 5,000 - 10,000 and 5,000 ESTs.

Simple reads will be performed in 5'. The libraries have not been subtracted or normalized, so after a first sequencing round, these sequences will be subtracted from the initial libraries and a second sequencing round will be carried out.