Functional characterization of sensory neuron membrane protein 1a involved in sex pheromone detection of Apolygus lucorum(Hemiptera:Miridae)

The mirid bug Apolygus lucorum(Hemiptera:Miridae)is a polyphagous pest that affects a wide range of host plants.Its control remains challenging mainly due to its rapid reproduction,necessitating an understanding of sex pheromone communication.The recognition of sex pheromones is vital for courtship and mating behaviors,and is mediated by various chemosensory-associated proteins.Among these,sensory neuron membrane protein(SNMP),a CD36-related protein,is suggested to play crucial roles in detecting sex pheromones.In this study,we employed transcriptomic and genomic data from A.lucorum and phylogenetic approaches,and identified four putative SNMP genes(AlucSNMP1a,AlucSNMP1b,AlucSNMP2a,and AlucSNMP2b)with full open reading frames.Expression analysis revealed the ubiquitous presence of AlucSNMP transcripts in multiple tissues,with only AlucSNMP1a exhibiting male-biased expression in the antennae,suggesting its potential role in male chemosensation.Functional analysis using the Xenopus oocyte expression system,coupled with two-electrode voltage clamp recording,demonstrated that the co-expression of AlucSNMP1a with specific pheromone receptors(PRs)and the Odorant receptor co-receptor(Orco)significantly enhanced electrophysiological responses to sex pheromones compared to the co-expression of PRs and Orco alone.Moreover,the results indicated that the presence of AlucSNMP1a not only affected the responsiveness to sex pheromones but also influenced the kinetics(activation and inactivation)of the induced signals.In contrast,the co-expression of AlucSNMP1b with AlucPR/Orco complexes had no impact on the inward currents induced by two pheromone compounds.An examination of the selective pressures on SNMP1 genes across 20 species indicated strong purifying selection,implying potential functional conservation in various insects.These findings highlight the crucial role of AlucSNMP1a in the response to sex pheromones.

Rashba效应和Zeeman效应对各向异性量子点中束缚磁极化子性质的影响

采用Pekar变分法和幺正变换相结合的方法研究了各向异性量子点中束缚磁极化子的Rashba效应和Zeeman效应.通过理论推导,得到束缚磁极化子基态能量的表达式.讨论了极化子基态能量与横向有效受限长度、纵向有效受限长度、磁场回旋共振频率、库仑束缚势的关系.由于晶体结构反演非对称性和时间反演非对称性,极化子能量发生Rashba自旋轨道分裂和Zeeman分裂.在强、弱磁场下,分别讨论了Zeeman效应和Rashba效应在能量分裂中所占的主导地位.由于声子和杂质的存在,极化子比裸电子态更稳定.

非对称量子阱中磁极化子的性质

采用Pekar变分法研究了磁场对非对称量子阱中极化子性质的影响,理论推导得到磁极化子基态能量的表达式,分别讨论了磁极化子基态能量与波矢、阱宽、磁场回旋共振频率及阱深的关系。研究表明磁极化子基态能量是波矢和磁场回旋共振频率的增函数,是阱宽和阱深的减函数。由于晶体结构反演的非对称性以及磁场的作用,极化子能量发生Rashba自旋-轨道分裂和Zeeman分裂,分别讨论了强弱磁场下Rashba效应和Zeeman效应在能量分裂中所占的主导位置。由于声子的存在降低了极化子的总能量,所以极化子态比裸电子态更稳定,能量分裂也更稳定。

n-octyl acrylate is a candidate sex pheromone component involved in courtship in parasitoid wasp Microplitis mediator

Sex pheromones are considered to play critical roles in partner communication of most parasitic Hymenoptera.However,the identification of sex pheromone components remains limited to a few families of parasitoid wasps.In this study,we functionally characterized a candidate sex pheromone component in Microplitis mediator(Hymenoptera:Braconidae),a solitary parasitoid of Noctuidae insects.We found that the body surface extract from female wasps could significantly stimulate courtship behavior of males.Gas chromatography-electroantennographic detection(GC-EAD)analysis revealed that a candidate semiochemical from extract triggered significant electrophysiological response of antennae of males.By performing gas chromatography-mass spectrometer(GC-MS)measurement,GC-EAD active compound was identified as n-octyl acrylate,a candidate sex pheromone component in female M.mediator.In electroantennogram(EAG)tests,antennae of male wasps showed significantly higher electrophysiological responses to n-octyl acrylate than those of females.Y-tube olfactometer assays indicated that male wasps significantly chose n-octyl acrylate compared with the control.Furthermore,male wasps showed a remarkable preference for n-octyl acrylate in a simulated field condition behavioral trial;simultaneously,n-octyl acrylate standard could also trigger significant courtship behavior in males.We propose that n-octyl acrylate,as a candidate vital sex pheromone component,could be utilized to design behavioral regulators of M.mediator to implement the protection and utilization of natural enemies.

中国劳动力市场化指数构建与检验

本文采用两个一级指标和四个二级指标构建中国劳动力市场化指数,比较全面地反映劳动力市场化的数量和价格因素变动。我们计算了2010年至2016年中国地级市层面劳动力市场化指数,并检验了其与宏观经济指标的相关性。结果显示,中国劳动力市场化程度在此期间取得了很大进展,进步的关键在于数量配置因素而非价格因素。不同地区及级别的城市劳动力市场化程度进展有较大差异。同时,外部有效性检验亦证实了此指数有较强的科学性。

Functional characterization of a Niemann-Pick type C2 protein in the parasitoid wasp Micropfitis mediator

Niemann-Pick type C2 （NPC2） is a type of small soluble protein involved in lipid metabolism and triglyceride accumulation in vertebrates and arthropods. Recent stud- ies have determined that NPC2 also participates in chemical communication of arthropods. In this work, two novel NPC2 proteins （MmedNPC2a and MmedNPC2b） in Microplitis mediator were identified. Real-time quantitative PCR （qPCR） analysis revealed that Mmed- NPC2a was expressed higher in the antennae than in other tissues of adult wasps compared with MmedNPC2b. Subsequent immunolocalization results demonstrated that NPC2a was located in the lymph cavities of sensilla placodea. To further explore the binding charac- terization of recombinant MmedNPC2a to 54 candidate odor molecules, a fluorescence binding assay was performed. It was found MmedNPC2a could not bind with selected fatty acids, such as linoleic acid, palmitic acid, stearic acid and octadecenoic acid. How- ever, seven cotton volatiles, 4-ethylbenzaldehyde, 3,4-dimethylbenzaldehyde, fl-ionone, linalool, m-xylene, benzaldehyde and trans-2-hexen-l-al showed certain binding abilities with MmedNPC2a. Moreover, the predicted 3D model of MmedNPC2a was composed of seven r-sheets and three pairs of disulfide bridges. In this model, the key binding residues for oleic acid in CjapNPC2 of Camponotus japonicus, Lue68, Lys69, Lys70, Phe97, Thr103 and Phe127, are replaced with Phe85, Ser86, His87, Leu113, Tyr119 and Ile143 in MmedNPC2a, respectively. We proposed that MmedNPC2a in M. mediator may play roles in perception of plant volatiles.

Molecular characterization and expression of sensory neuron membrane proteins in the parasitoid Microplitis mediator (Hymenoptera: Braconidae)

Sensory neuron membrane proteins(SNMPs),homologs of the human fatty acid transport protein CD36 family,are observed to play a significant role in chemoreception,especially in detecting sex pheromone in Drosophila and some lepidopteran species.In the current study,two full‐length SNMP transcripts,MmedSNMP1 and MmedSNMP2,were identified in the parasitoid Microplitis mediator(Hymenoptera:Braconidae).Quantitative real‐time polymerase chain reaction analysis showed that the expression of MmedSNMP1 was significantly higher in antennae than in other tissues of both sexes.In addition,the MmedSNMP1 transcript was increased dramatically in newly emerged adults and there were no significant differences between adults with or without mating and parasitic experiences.However,compared with MmedSNMP1,the expression of MmedSNMP2 was widely found in various tissues,significantly increased at half‐pigmented pupae stage and remained at a relatively constant level during the following developmental stages.It was found that MmedSNMP1 contained eight exons and seven introns,which was highly conserved compared with other insect species.In situ hybridization assay demonstrated that MmedSNMP1 transcript was distributed widely in antennal flagella.Among selected chemosensory genes(odorant binding protein,odorant receptor,and ionotropic receptor genes),MmedSNMP1 only partially overlapped with MmedORco in olfactory sensory neurons of antennae.Subsequent immunolocalization results further indicated that MmedSNMP1 was mainly expressed in sensilla placodea of antennae and possibly involved in perceiving plant volatiles and sex pheromones.These findings lay a foundation for further investigating the roles of SNMPs in the chemosensation of parasitoids.

Characterization and target gene analysis of microRNAs in the antennae of the parasitoid wasp Microplitis mediator

MicroRNAs(miRNAs),a class of non-coding single-strand RNA molecules encoded by endogenous genes,are about 21–24 nucleotides long and are involved in the post-transcriptional regulation of gene expression in plants and animals.Generally,the types and quantities of miRNAs in the different tissues of an organism are diverse,and these divergences may be related to their specific functions.Here we have identified 296 known miRNAs and 46 novel miRNAs in the antennae of the parasitoid wasp Microplitis mediator by high-throughput sequencing.Thirty-three miRNAs were predicted to target olfactory-associated genes,including odorant binding proteins(OBPs),chemosensory proteins,odorant receptors(ORs),ionotropic receptors(IRs)and gustatory receptors.Among these,17 miRNAs were significantly highly expressed in the antennae,four miRNAs were highly expressed both in the antennae and head or wings,while the remaining 12 miRNAs were mainly expressed in the head,thorax,abdomen,legs and wings.Notably,miR-9a-5p and miR-2525-3p were highly expressed in male antennae,whereas miR-1000-5p and novel-miR-13 were enriched in female antennae.The 17 miRNAs highly expressed in antennae are likely to be associated with olfaction,and were predicted to target one OBP(targeted by miR-3751-3p),one IR(targeted by miR-7-5p)and 14 ORs(targeted by 15 miRNAs including miR-6-3p,miR-9a-5p,miR-9b-5p,miR-29-5p,miR-71-5p,miR-275-3p,miR-1000-5p,miR-1000-3p,miR-2525-3p,miR-6012-3p,miR-9719-3p,novel-miR-10,novel-miR-13,novel-miR-14 and novel-miR-28).These candidate olfactory-associated miRNAs are all likely to be involved in chemoreception through the regulation of chemosensory gene expression in the antennae of M.mediator.