Molecular Characterization and Expression Pattern of Two General Odorant Binding Proteins from the Diamondback Moth, Plutella xylostella

Abstract

In the Lepidoptera, odorant signals are thought to be mediated by general odorant binding proteins (GOBPs) in the sensillar lymph surrounding the olfactory receptors. We describe the identification and characterization of two new cDNAs encoding GOBPs from the antennae of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), a species for which no GOBPs have been identified to date. We focused our investigation on this olfactory protein family by using reverse transcription-polymerase chain reaction strategies. The deduced amino acid sequences of PxylGOBP1 and PxylGOBP2 revealed open reading frames of 168 and 163 amino acids, respectively, with six cysteine residues in conserved positions relative to other known GOBPs. The alignment of the mature PxylGOBPs with other Lepidoptera GOBPs showed high sequence identity (70-80%) with other full-length sequences from GenBank. Sequence identity between PxylGOBP1and PxylGOBP2 was only 50%, suggesting that the two proteins belong to different classes of lepidopteran GOBPs. The expression patterns of the two PxylGOBP genes, with respect to tissue distribution and sex, were further investigated by reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR. Although the two GOBP genes were expressed only in the antennae of both sexes, reflecting the antennal specificity of GOBPs, the transcription levels of these genes depended on the sex, the age, the mating status, and the genes.

Application of Cydia pomonella expressed sequence tags: Identification and expression of three general odorant binding proteins in codling moth

“…GOBPs are a subfamily of OBPs that are expressed in lepidopteran antennae, and have been shown to bind pheromones (Gong et al ., ; Leal et al ., ; Zhou et al ., ; He et al ., ; Liu et al ., ), and in Lepidoptera consist of two members, GOBP1 and GOBP2 (Vogt et al ., ; Krieger et al ., ; Newcomb et al ., ; Vogt et al ., ; Jin et al ., ; Leal et al ., ; Zhang et al ., ). A unique finding in this study was the identification of three C. pomonella transcripts that encode putative GOBPs.…”

“…Within the annotated portion of the C. pomonella ESTs, we identified gene transcripts encoding 12 putative CSPs and 18 putative OBPs (which included five members of the PBP subfamily and three members of the GOBP subfamily). These orthologs and numbers are consistent with CSPs and OBPs identified in transcriptomes of other lepidopterans (Gong et al ., ; Jordan et al ., ; Ozaki et al ., ; Zhang et al ., ; Grosse‐Wilde et al ., ; Legeai et al ., ). Phylogenetic analysis of CSP and OBP proteins from C. pomonella showed a one‐to‐one orthology with genes from other Lepidoptera.…”

Expression profile and ligand‐binding characterization of odorant‐binding protein 2 from Batocera horsfieldi (Hope)

“…Mating status has been shown to correlate with OBP expression in Plutella xylostella (Zhang et al. ) and Nilaparvata lugens (Zhou et al. ).…”

General Guidelines for Authors for Submission of Manuscripts that Contain Molecular Biological Content

“…A) Isolation, identification, and/or expression of a gene or collections of genes coding for pheromone or odorant binding proteins, olfactory receptors, enzymes involved in pheromone biosynthesis, or genes involved in plant defense (e.g., Xiu and Dong 2007;Zhang et al 2009;Shivaji et al 2010 (Han et al 2009;Sethi et al 2009). D) Characterization of peptides and other large biomolecules that serve as olfactory signals (e.g., Robertson et al 2007).…”

“…Because real-time PCR is a quantification method highly dependent on the quality of the template (RNA or cDNA) and the efficiency of the amplification (C q ), authors should include tables that show the efficiencies of the amplification reaction for each gene monitored, including the reference gene(s). An example of this can be found in Zhang et al (2009) (Supplemental Data Tables 1 and 2). R-squared values from the standard curves for genes analyzed by real-time PCR (including the reference gene(s) and the no-treatment controls) should also be included in these tables.…”