title: Molecular characterization and phylogenetic analysis of three odorant binding protein gene transcripts in Dendrolimus species (Lepidoptera: Lasiocampidae).
abstract: Pine caterpillar moths, Dendrolimus spp. (Lepidoptera: Lasiocampidae), are serious economic pest of pines. Previously, phylogenetic analyses of Dendrolimus using different methods yielded inconsistent results. The chemosensory systems of insects may play fundamental roles in promoting speciation. Odorant-binding proteins (OBPs) participate in the first step of odor detection. Studying the evolution of OBPs in closely related species may help us to identify their role in speciation. We identified three OBPs - one pheromone-binding protein and two general odorant-binding proteins - from male antennae of four Dendrolimus species, D. superans (Butler), D. punctatus (Walker), D. kikuchii Matsumura, and D. houi Lajonquiere, the olfactory recognition systems of which had not been previously investigated. We analyzed their molecular characteristics and compared their sequences to those of OBPs in D. tabulaeformis Tsai et Liu. Ka/Ks ratio analyses among the five Dendrolimus species indicate that PBP1 genes experienced more evolutionary pressure than the GOBPs. Phylogenetic relationships of PBP1 and GOBP1 both indicated that D. houi was the basal species, then branched D. kikuchii, while D. tabulaeformis, D. punctatus, and D. superans evolved more recently. These relationships are consistent with the changes in sex pheromone components of these five species. Dendrolimus tabulaeformis and D. punctatus are closely related sister species. However, the distances among GOBP2 sequences in the five Dendrolimus were very short, and the relationships of D. houi and D. kikuchii could not be resolved. Integrating our results with those of previous studies, we hypothesized that D. kikuchii, D. punctatus and D. superans evolved from the basal ancestor because of sex pheromone mutations and environmental pressure.
authors: Key Laboratory of Forest Protection, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, State Forestry Administration, Beijing, China.
authors: Su-Fang
authors: SF
authors: Zhang
authors: Zhen
authors: Z
authors: Zhang
authors: Xiang-Bo
authors: XB
authors: Kong
authors: Hong-Bin
authors: HB
authors: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002681:China; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009036:Moths / Q000145:classification* / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D018035:Receptors, Odorant / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment; D013045:Species Specificity
chemical_list: D018076:DNA, Complementary; D019476:Insect Proteins; D018035:Receptors, Odorant; C045648:odorant-binding protein
keywords: Dendrolimus; Ka/Ks; general odorant-binding protein; pheromone-binding proteins; phylogenetic; sex pheromone