PUTATIVE ODORANT BINDING PROTEINS FROM COCKROACHESARE HIGHLY CONSERVED IN PRIMITIVE ORDERS.

Jean-Francois Picimbon and Walter Soares Leal
Laboratory of Chemical Prospecting, National Institute of Sericulturaland Entomological Science, 1-2 Ohwashi, Tsukuba 305, Japan.

Pheromones from cockroaches are remarkably different from those of moths,suggesting that these two Orders may have evolved distinct olfactory systems.This difference is mirrored in the Odorant Binding Proteins (OBPs), whichare presumably selective towards pheromone ligands. In moths, the olfactorysystem involves Pheromone Binding Proteins (PBPs) and General Odorant BindingProteins (GOBPs). N-terminal sequences of OBP-like proteins from cockroachesrevealed that phylogenetically primitive insects express highly conservedOBPs, which show no homology to the PBPs and GOBPs of the more advancedLepidoptera. Our findings suggest that cockroach OBPs can be divided intoOBPs homologous to OS-D, a product of cloning olfactory-related genes fromDrosophila melanogaster; the ones related to a phasmid (Sipyloideasipylus ) OBP, and others without any homology to any known OBPs.