Identification of Host-Plant Volatiles and Characterization of Two Novel General Odorant-Binding Proteins from the Legume Pod Borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae)

• DOI: 10.1371/journal.pone.0141208
• Publication Date: 2015-10-30T18:25:30Z
• Authors: Jing Zhou; Na Zhang; Pan Wang; Shichang Zhang; Daiqin Li; Kaiyu Liu; Guoxiu Wang; Xiaoping Wang; Hui Ai
• Keywords: Crambidae; Electroantennography; Odorant-binding protein; Chemical Ecology

Chemoreception is a key feature in selection of host plant by phytophagous insects, and odorant-binding proteins (OBPs) are involved chemical communication both insects vertebrates. The legume pod borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) one the pest species cowpea widely distributed throughout tropical subtropical regions, causing up to 80% yield loss. In this study, we investigated electrophysiological responses female M. floral volatiles from V. unguiculata. Seventeen electroantennogram-active compounds were identified unguiculata coupled gas chromatography-electroantennography (GC-EAD) chromatography-mass spectrometry (GC-MS). Then, cloned two novel full-length GOBP genes (MvitGOBP1 MvitGOBP2) antennae using reverse transcription PCR. Protein sequence analysis indicated that they shared high similarity with other Pyralididae insect GOBPs had typical six-cysteine signature. Real-time PCR MvitGOBP1-2 mRNA was highly expressed adult several thousands-fold difference compare tissue. Next, recombinant Escherichia coli purified Ni ion affinity chromatography. Fluorescence binding assays demonstrated different affinities 17 volatile odorant molecules including butanoic acid butyl ester, limonene, 4-ethylpropiophenone, 1H-indol-4-ol, octyl ester 2-methyl-3-phenylpropanal. field trapping experiment, these six could effectively attract moths showed significant compared blank lure. These results suggested MvitGOBPs seventeen likely function olfactory behavior response moths, which may have played crucial roles oviposition sites. provide useful information for exploring efficiency monitoring integrated management strategies borer field.