Neuropeptide and neurohormone precursors in the pea aphid, Acyrthosiphon pisum

Authors


Denis Tagu, UMR 1099 INRA/Agrocampus Ouest/Université Rennes 1, BiO3P, Domaine de la Motte, F-35653 Le Rheu, France. Tel.: +33 223 48 51 65; fax: +33 223 48 51 50; e-mail: denis.tagu@rennes.inra.fr
Jan Veenstra, Université de Bordeaux, CNRS, UMR 5228, CNIC, Talence, France. Tel: +33 540 008 751; Fax: +33 540 008 743; e-mail: j.veenstra@cnic.u-bordeaux1.fr

Abstract

Aphids respond to environmental changes by developing alternative phenotypes with differing reproductive modes. Parthenogenetic reproduction occurs in spring and summer, whereas decreasing day lengths in autumn provoke the production of sexual forms. Changing environmental signals are relayed by brain neuroendocrine signals to the ovarioles. We combined bioinformatic analyses with brain peptidomics and cDNA analyses to establish a catalogue of pea aphid neuropeptides and neurohormones. 42 genes encoding neuropeptides and neurohormones were identified, of which several were supported by expressed sequence tags and/or peptide mass analyses. Interesting features of the pea aphid peptidome are the absence of genes coding for corazonin, vasopressin and sulfakinin and the presence of 10 different genes coding insulin related peptides, one of which appears to be very abundantly expressed.

Ancillary