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Nutrient metabolism is crucial for the survival of insects through the diapause. However, little is known about the metabolic mechanism of prolonged diapause. The sawfly, Cephalcia chuxiongica (Hymenoptera: Pamphiliidae), is a notorious defoliator of pine trees in southwest China. One of the distinguishing biological characteristics of this pest is the prolonged diapause of about 1.5 years. In this study, the body lipid, carbohydrate (total body sugar, glycogen, trehalose, and glucose), protein, and glycerol contents were measured in diapausing larvae of C. chuxiongica. The results showed that the changes of biochemical composition in C. chuxiongica are associated with the diapause initiation, maintenance, and termination phases. During the initiation phase, trehalose, glucose, and glycerol increased significantly, but glycogen decreased sharply. In general, the lipid, carbohydrate, and glycerol levels decreased gradually across the maintenance phase. At termination phase, the contents of glycogen and lipid persistently decreased, while an increase of trehalose, glucose, and glycerol contents were detected. The protein level was significantly higher at maintenance phase than at initiation and termination phases. It was also found that elevation of trehalose, glucose, and glycerol contents occurred in winter. These implies that the metabolites with altered levels in diapausing larvae of C. chuxiongica are responsible for maintaining a prolonged development and overwintering.

Noorda blitealis (Lepidoptera: Pyraloidea: Crambidae) is a major defoliating pest of Moringa trees. Focusing on its mating and reproduction, here we sequenced and analyzed the transcriptome of its pheromone glands (PGs) with a combination of Illumina sequencing, bioinformatics and phylogenetics approaches, coupled with a genome-based analysis. Transcriptome sequencing led to the yields of approximately 162 million clean reads, which were assembled into 60,578 unigenes and 121,692 transcripts, respectively. From the transcriptome, totally 117 genes encoding eight pheromone biosynthesis enzymes and one pheromone degradation enzyme were identified, 90 of which had complete open reading frames. A comparative analysis between PGs and bodies (removing PGs) revealed a large number of differentially expressed genes, including 79 pheromone biosynthesis and degradation related genes. Of the identified genes, NbliDES12 belonging to the △11 desaturase group was likely to a strong candidate for the desaturation of sex pheromones in N. blitealis, as implied by phylogenetic analyses and expression profiles. Finally and most notably, through genome and transcriptome analyses we discovered, for the first time, a novel aldehyde oxidase 6 (AOX6) group of the superfamily Pyraloidea that have been slightly expanded by gene duplications. Moreover, each orthologous AOX group shared highly conserved gene structure. Together, this current study has characterized the genes associated with sex pheromone biosynthesis and degradation from the PG transcriptome of N. blitealis, and more importantly, identifies a novel AOX group of the Pyraloidea.

Lepidoptera (moths and butterflies) and Trichoptera (caddisflies), belonging to the superorder Amphiesmenoptera, are the most diverse insect orders as representatives of the terrestrial and aquatic insects, respectively. The insects of the two orders possess different biological and behavioral characteristics, especially their larvae, presumably resulting in the differences of the ionotropic receptor (IR) genes in numbers, sequence characteristics or gene structure. Here, we employed genomics, transcriptomics, bioinformatics, phylogenetics and molecular biology strategies to characterize the IR gene repertoire in Lepidoptera and Trichoptera. Genome and transcriptome analyses with exhaustive homology-based searches and manual efforts, in 32 lepidopterans and five trichopterans, led to the identification of 1449 genes encoding IRs with 1170 full-length sequences, representing the most comprehensive set of chemoreceptor superfamilies across the Amphiesmenoptera. Analysis of gene gains and losses in orthologous groups implied that some IRs were lost in related species, and multiple gene copies occurred mainly in divergent IRs (D-IRs) by gene duplications. Phylogenetic analysis of 2442 IR proteins from 67 species revealed that Lepidoptera and Trichoptera IRs could be classified into three subfamilies, i.e., 14 antennal IRs (A-IRs), five Lepidoptera-specific IRs (LS-IRs) and four D-IRs. Of the three subfamilies, A-IRs and LS-IRs members within orthologous groups exhibited high conservation of gene structure, but D-IRs shared extremely low amino acid identities (below 30%). Expression profiles revealed functional diversities of IRs from Bombyx mori and Papilio xuthus involving smell, taste or reproduction, in which some genes displayed sex-biased expression in antennae associated with specific chemosensory behaviors of female or male adults. Our current study has provided insights into the evolution, conservation and divergence of IRs between/within Lepidoptera and Trichoptera, and allows for further experiments to investigate IR functions.

Through an exhaustive homology-based approach, coupled with manual efforts, we annotated and characterized 128 sensory neuron membrane proteins (SNMPs) from genomes and transcriptomes of 22 coleopteran species, with 107 novel candidates. Remarkably, we discovered, for the first time, a novel SNMP group, defined as Group 4 based on the phylogeny, sequence characteristics, gene structure and organization. The lineage-specific expansions in SNMPs occurred mainly in the family Scarabaeidae, harboring 12 representatives in Onthophagus taurus as a typical gene duplication and the most massive set of SNMPs in insects to date. Transcriptome sequencing of Rhaphuma horsfieldi resulted in the yields of approximately 611.9 million clean reads that were further assembled into 543,841 transcripts and 327,550 unigenes, respectively. From the transcriptome, 177 transcripts encoding 84 odorant (ORs), 62 gustatory (GRs), 20 ionotropic (IRs), and 11 ionotropic glutamate (iGluRs) receptors were identified. Phylogenetic analysis classified RhorORs into six groups, RhorGRs into four subfamilies, and RhorIRs into 10 conserved antennal IRs and one divergent IRs. Expression profiles revealed that over 80% of chemosensory genes were specifically or highly transcribed in antennae or tarsi, suggestive of their olfactory and/or gustatory roles. This study has greatly complemented the resources for chemosensory genes in the cerambycid beetles, and most importantly, identifies a novel group of SNMPs in Coleoptera.

The bark beetle, Tomicus yunnanensis (Coleoptera: Scolytinae), is a seriously destructive pest of Yunnan pine (Pinus yunnanensis) and is distributed solely in Southwestern China. It has been a challenge to control this pest owing to its resistance to chemical pesticides, which have been used as the main control strategy of this species in recent years. Since this approach will continue until an alternative mitigation strategy is implemented, it is essential to develop novel or improved biocontrol approaches. In the current study, we aimed to identify most, if not all, of the bark beetle's chemosensory genes, and to address their respective phylogenetic relationships and expression characteristics. Digital gene expression (DGE) profiling and a comparison of the profiles at three developmental stages yielded 40,287,265 clean reads and a large number of differentially expressed genes (DEGs), with 21 up- and 20 down-regulated DEGs involved in chemoreception. Transcriptome of the three mixed stages revealed a total of 80 transcripts encoding chemosensory-related proteins comprising 45 odorant-binding proteins (OBPs), 12 chemosensory proteins (CSPs), 20 receptor proteins [9 odorant receptors (ORs), 8 gustatory receptors (GRs) and 3 ionotropic receptors (IRs)] and 3 sensory neuron membrane proteins (SNMPs). As many as 38 full-length sequences were acquired with a combination of transcriptomic analysis and rapid amplification of cDNA ends (RACE) strategy. Phylogenetic analysis showed that T. yunnanensis OBPs were clustered into four sub-groups: 27 Minus-C OBPs, 5 antennal binding proteins (ABPIIs), 10 Classic OBPs and one Plus-C OBP; meanwhile, the ORs were grouped into four clades (1, 2, 7b and Orco). Expression profiles revealed that 66 of 80 genes were detected in the three DGE libraries, and 15 soluble olfactory proteins were antennae-predominant, possibly guiding olfactory-associated behaviors of this beetle. Taken together, our study has provided valuable data for further functional studies of this beetle and will facilitate the identification of potential molecular targets associated with chemosensory reception for use in biocontrol strategies.

Acid phosphatase (ACPase) is a common component in venom of parasitoids. Although extensive researches regarding this enzyme have been conducted in many other organisms, its characteristics as a venomous enzyme are still sparsely known. In this study, we aimed to reveal the gene expression patterns, and structural and biochemical properties of an ACPase from the venom of Scleroderma guani. The cloned open reading frame of venomous ACPase gene of S. guani was 1218 bp encoding 406 deduced amino acids, shared 40% and 41% identities to ACPases from venoms of Apis mellifera and Pteromalus puparum, respectively. The structural analysis of this ACPase implied common functions and differences to the honeybee venom ACPase. qPCR analysis showed that this gene was abundantly expressed in the venom apparatus, and most highly expressed in the adult stage after one and three days emergence. Activity assay using p-nitrophenyl phosphate as the substrate revealed that the optimal pH and temperature for this venomous enzyme was 4.8 and 45 °C, respectively. NaF is an effective inhibitor for it. The results will enrich our knowledge for the ACPase as toxin, which may contribute to further uncovering its role involved in parasitism.

The genital systems of insects are undoubtedly of great key for the success of mating and population reproduction. In the meantime, morphological and ultrastructural characteristics of the reproductive systems also provide valuable evidences for the studies of taxonomy, reproductive biology and evolutionary biology. More previously, the reproductive system of female Nasonia vitripennis was already described. To complement the information of reproductive systems from this species, the male reproductive system was here dissected and characterized by light microscopy and transmission electron microscopy. Results showed that the system follows the pattern of most Hymenoptera species: paired testes with one follicle, deferent ducts, seminal vesicles, accessory glands and a fused ejaculatory duct ultimately connected to the external aedeagus. Histologically, the testes, seminal vesicles and accessory glands are all composed of three portions, all of which include epithelial and luminal regions. In addition, both lipidic inclusions and nuclei are presented in the three organs with variable sizes and shapes. Spermatozoa are observed in the testes and seminal vesicles, and also vary considerably in size and shape, suggesting different phases of spermatogenesis. Mitochondria are abundant in seminal vesicles and accessory glands. Notably, membranous inclusions and Golgi complexes are found only in seminal vesicles, whereas secretory granules are presented only in accessory glands, being indicative of organ or age specificity. Together, this study complements the information of the reproductive systems from N. vitripennis , and provides an extensive resource for taxonomy, reproductive biology and evolutionary biology.

The plant bug, Pachypeltis micranthus (Hemiptera: Miridae), is a natural enemy of the invasive alien weed Mikania micrantha with a widespread distribution in South China as well as other countries. The interactions of P. micranthus and its host M. micrantha , associated with a linkage of host recognition, are of great importance for its survival and reproduction. The identification of olfactory-related genes is undoubtedly the initially key step, to uncover how P. micranthus perceives and recognizes the specific host plant M. micrantha . Here, we constructed an antennal full length cDNA library from P. micranthus antennae. By sequencing, a total of 13 transcripts encoding chemosensory-related genes were identified, comprising nine odorant-binding proteins ( OBPs ), three chemosensory proteins ( CSPs ) and one odorant receptor ( OR ). All identified OBPs and CSPs shared classic characteristics of conserved cysteines and a signal peptide. Expression profiles by quantitative real time PCR (qPCR) revealed that as many as 12/13 chemosensory genes were expressed predominantly in the antennae at a sex-biased pattern, strongly linking to their specific olfactory functions. Notably, expression of all these genes was also differentially detected in legs of both sexes with an exception of PmicOBP7 , indicative of their functional differentiation between female and male adults. Further, molecular docking of PmicOBP6 and CSP1 to behaviorally active compounds provided the potentially key residues for ligand-binding, which deserves further studies.

A dicyanoisophorone-based probe with two-photon absorption and NIR emission was developed for the in vivo fluorescence imaging of amyloid-β plaques, which exhibited high selectivity toward Aβ aggregates over other intracellular proteins. The detection limit was calculated to be as low as 109 nM. In vivo imaging studies indicated that the probe could penetrate the blood–brain barrier and label Aβ plaques in the living transgenic mice, and its specific binding to cerebral Aβ plaques was further confirmed by one- and two-photon ex vivo fluorescence imaging. All these results featured its promising application prospects for amyloid-β sensing in basic research and biomedical research.

Similar to venom found in most venomous animals, parasitoid venoms contain a complex cocktail of proteins with potential agrichemical and pharmaceutical use. Even though parasitoids are one of the largest group of venomous animals, little is known about their venom composition. Recent few studies revealed high variated venom composition existing not only in different species but also between closely related strains, impling that increasing information on the venom proteins from more greater diversity of species of different taxa is key to comprehensively uncover the complete picture of parasitoid venom. Here, we explored the major protein components of the venom of ectoparasitic ant-like bethylid wasp, Scleroderma guani by an integrative transcriptomic-proteomic approach. Illumina deep sequencing of venom apparatus cDNA produced 49,873 transcripts. By mapping the peptide spectral data derived from venom reservoir against these transcripts, mass spectrometry analysis revealed ten main venom proteins, including serine proteinase, metalloprotease, dipeptidyl peptidase IV, esterase, antithrombin-III, acid phosphatase, neural/ectodermal development factor IMP-L2 like protein, venom allergen 3, and unknown protein. Interestingly, one serine proteinase was firstly identified with rarely high molecular weight about 200 kDa in parasitoid venom. The occurrence of abundant acid phosphatase, antithrombin-III and venom allergen 3 demonstrated that S. guani venom composition is similar to that of social wasp venoms. All identified venom genes showed abundantly biased expression in venom apparatus, indicating their virulent functions involved in parasitization. This study shed light on the more better understanding of parasitoid venom evolution across species and will facilitate the further elucidation of function and toxicity of these venom proteins.

Plants are equipped with the capacity to respond to a large number of diverse signals, both internal ones and those emanating from the environment, that are critical to their survival and adaption as sessile organisms. These signals need to be integrated through highly structured intracellular networks to ensure coherent cellular responses, and in addition, spatiotemporal actions of hormones and peptides both orchestrate local cell differentiation and coordinate growth and physiology over long distances. Further, signal interactions and signaling outputs vary significantly with developmental context. This review discusses our current understanding of the integrated intracellular and intercellular signaling networks that control plant growth.

The longhorned beetles, Rhaphuma horsfieldi and Xylotrechus quadripes, are two polyphagous insects with larvae feeding on different host plants. In this study, we identified and characterized three gene superfamilies of cytochrome P450s (CYPs), carboxylesterases (COEs) and glutathione-S-transferases (GSTs) involved in the detoxification of endobiotics (e.g., hormones and steroids) and xenobiotics (e.g., insecticides, sex pheromones and plant allelochemicals) through a combination approach of bioinformatics, phylogenetics, expression profiles and genomics. Transcriptome analyses led to the identification of 281 transcripts encoding 135 P450s, 108 COEs and 38 GSTs from the two beetles, coupled with comparative studies of detoxification genes among coleopteran species, suggesting a correlation between host range and the sizes of P450 or COE gene repertoires. The P450s of two beetles were phylogenetically classified into four clades, representing the majority of genes in the CYP3 clan. The COEs from R. horsfieldi and X. quadripes were separately grouped into 11 and 10 clades, and the GST superfamily was assigned into six clades. Expression profiles revealed that the detoxification genes were broadly expressed in various tissues as an implication of functional diversities. Ultimately and more importantly, five alternative splicing events in the Epsilon GSTs, including RhorGSTe7.1/GSTe7.2 and XquaGSTe3.1/GST3.2, were acquired in Coleoptera, in which these genes and their orthologs shared highly conserved gene structure. Our current study has complemented the resources for the detoxification genes in the family Cerambycidae, and allows for functional experiments to identify candidate molecular targets involved in pest resistance to insecticides like organophosphates, organochlorines and pyrethroids.

Chemosensory proteins (CSPs) are believed to be important in the detection of semiochemicals, and have been reported to be involved in development, molting, leg regeneration and phase transition. In the current study, six CSP genes were identified in the beet armyworm Spodoptera exigua , namely SexiCSP1-6, from the full length cDNA library. Multiple alignment and phylogenetic analysis indicated that they were very diverse as seen in CSPs of other insect species. Expression patterns determined by quantitative real-time PCR (qPCR) revealed that they were highly expressed in antenna. SexiCSP1-3, SexiCSP5 and SexiCSP6 were male antenna-biased, while SexiCSP4 was female-biased in the antenna. In addition to antenna, they were expressed at high levels in legs and wings, suggesting potential roles in contact chemoreception and non-olfactory roles. Compared with the expression in antenna, legs and wings, only SexiCSP1 showed relatively high expression in heads, thoraxes and abdomen. These results extended olfactory gene resource in the beet armyworm and provided basis for further gaining a better understanding of CSPs roles in this pest.

Three antibacterial peptide genes, coleoptericins A, B and C, were identified from the yellow meal worm beetle, Tenebriomolitor. Their cDNA sequences encoded 13.01, 13.13 and 14.16 kDa peptides, respectively. Their deduced amino acid sequences showed 16?34% identity with other coleopteran coleoptericins, containing over 20% glycine. These genes were essentially expressed in fat body and hemocytes, and at late-instar larval and pupal stages. Their transcriptswere upregulated by bacterial challenge and Scleroderma guani parasitization. It suggests that triggered coleoptericin transcription is applied to prevent host potential infection during parasitization.