Submitted to: Chemical Senses
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/21/1999
Publication Date: N/A
Interpretive Summary: The tarnished plant bug, Lygus lineolaris (Hemiptera, Heteroptera: Miridae) is a pest of a number of economically important crops. We have carried out research to understand the mechanisms of chemical reception in the plant bug. Behavioral cues, such as sex pheromones and food/oviposition-site odors, have not been identified for this pest. This report expands on our previous studies identifying a Lygus antennal specific protein (LAP) most likely involved in chemical reception in the plant bug. The full length sequence of LAP was deduced through molecular cloning of the corresponding cDNA. This sequence information allowed positive identification of LAP as an Odorant Binding Protein (OBP) through comparisons with gene data banks. As an OBP, LAP would be involved in the first biochemical steps in odor reception in the plant bug. Our studies further showed that the LAP gene is expressed in correlation with the transition to adult behavior, including possibly reproduction. In a broader sense our results were useful in estimating the relatedness of LAP to other OBPs and the distribution of similar sequences among economically important groups of insects. Elucidation of the specificity of LAP-odorant interactions may be useful in development of novel, environmentally friendly methods of control for this pest.
Technical Abstract: Insect Odorant Binding Proteins (OBP) have been identified from numerous species repressing several insect orders, including Lepidoptera, Diptera, Coleoptera and Hymenoptera. All of these are holometabolous insects belonging to a presumed monophyletic division of insects known as the Endopterygota. Recently, an antennal protein with OBP-like properties was identified from Lygus lineolaris, a hemipteran insect representing the Hemipteroid Assemblage, a division sister to the Endopterygota. The full length sequence of LAP is presented in this report, and shown to be significantly related to the OBP-related protein family, especially the OS-E and OS-F proteins of Drosophila, the ABPX proteins of Lepidoptera and the OBPRP proteins of the Coleoptera. Current models of OBP action under investigation suggest that OBPs are the initial biochemical step in odor recognition capable of some level of odor discrimination. Assuming that the OBP-related proteins represent a homologous family, the identification of LAP significantly expands the phylogenetic depth of that family and its underlying roll in odor detection to encompass all members of the Endopterygota and Hemipteroid Assemblage, including many species of considerable agricultural and health-related importance.