Molecular and functional characterization of three odorant-binding proteins from the wheat blossom midge,Sitodiplosis mosellana  

作　　者：Wei-Ning Cheng Yu-Dong Zhang Wei Liu Guang-Wei Li Keyan Zhu-Salzman 

机构地区：[1]Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau,Ministry of Agriculture,Northwest A&F University,Yang ling,Shaanxi,China [2]Shaanxi Key Laboratory of Chinese Jujube,Van'an University,Van'an,Shaanxi,China [3]Department of Entomology,Texas A&M University,College Station,TX,USA

出　　处：《Insect Science》2020年第4期721-734,共14页昆虫科学（英文版）

基　　金：This research was supported by the National Natural Science Foundation of China(Grant No.31371933);the National Key Research and Development Program of China(Grant No.2018YFD0200402);Science and Technology Planning Project of Yangling Demonstration Zone,China(Grant No.2018NY-07).

摘　　要：Sitodiplosis mosellana,a periodic but devastating wheat pest,relies on wheat spike volatiles as a cue in sclecing hosts for oviposition.Insect odorant-binding proteins(OBPs)are thought to play essential roles in filtering,binding and transporting hydropho-bic odorant molecules to specific receptors.To date,the molecular mechanisms underlying S.mosellana olfaction are poorly understood.Here,three S.mosellana antenna-specific OBP genes,SmosOBPII,16 and 21,were cloned and bacterially expressed.Binding properties of the recombinant proteins to 28 volatiles emitted from wheat spikes were in-vestigated using fluorescence competitive binding assays.Sequence analysis suggested that these SmosOBPs belong to the Classic OBP subfamily.Ligand-binding analysis showed that all three SmosOBPs preferentially bound alcohol,ester and ketone com-pounds,and SmosOBP11 and 16 also selectively bound terpenoid compounds.In par-ticular,the three SmosOBPs had high binding affinities(Ki<20μmol/L)to 3-hexanol and cis-3-hexenylacetate that elicited strong electroantennogram(EAG)response fromfemale antennae.In addition,SmosOBP11 displayed significantly higher binding(Ki<8μmo/L)than SmosOBP16 and 21 to l-octen-3-ol,D-panthenol,a-pinene and heptyl acetate which elicited significant EAG response,suggesting that SmosOBP11 plays a ma-jor role in recognition and transportation of these volatiles.These findings have provided important insight into the molecular mechanism by which S.mosellana specifically rec-ognizes plant volatiles for host selection,and have facilitated identification of effective volatile attractants that are potentially useful for pest monitoring and trapping.

关 键 词：binding assay electroantennogram response host selection odorant-binding protein Sitodiplosis mosellana wheat spike violates 

分 类 号：Q96[生物学—昆虫学]