BackgroundL. decemlineata is an exotic invasive insect pest, and invaded in Xinjiang Uygur autonomous region in China in the 1990s from Kazakhstan. It is a notorious defoliator of potato throughout most of the northern Xinjiang in current, and often causes extremely large yield losses of potato.ResultsThe expression stability of nine L. decemlineata house-keeping genes (Actin, ACT1 and ACT2; ADP-ribosylation factor, ARF1 and ARF4; TATA box binding protein, TBP1 and TBP2; ribosomal protein RP4 and RP18; translation elongation factor 1α EF1α) was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) in seven developmental stages, three larval tissues and two insecticide treatments. The results were analyzed using three software programs: geNorm, NormFinder and BestKeeper. Although there was no consistent ranking observed among the house-keeping genes across the samples, the overall analysis revealed that RP18, RP4, ARF1, and ARF4 were the four most stable house-keeping genes. In contrast, ACT1 and ACT2, two of the most widely used reference genes, had the least stability. Our results suggest that the combined use of the four most stably expressed genes may produce optimal normalization for qRT-PCR.ConclusionsThe expression stability of the house-keeping genes varies among different developing stages, in different tissues and under different experimental conditions. Our results will enable a more accurate and reliable normalization of qRT-PCR data in L. decemlineata.

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The climate warming trend appears to be evident with an increasing frequency of drought events in Shaanxi Province of China, which may have contributed to an increase in outbreaks of the English grain aphid, Sitobion avenae (Fabricius). To explore the potential effects of water-deficit stress on aphid outbreak risks, clones of S. avenae were collected from semi-arid and moist areas of Shaanxi. The life histories of collected clones were then compared on wheat under well-watered and moderately water-stressed conditions in the laboratory. Our results demonstrated that semi-arid area clones of S. avenae had longer developmental times, shorter reproductive times, lower fecundities, and lower net reproductive rates compared with moist area clones. Age-specific reproductive rates of moist area clones tended to be higher than those of semi-arid area clones. Significant differences between semi-arid and moist area clones were found for the survival functions when tested under water-stressed conditions, and semi-arid area clones tended to have a lower survival rate than moist area clones throughout their lives. "Population origin" (i.e., semi-arid and moist area clones) and "clone" together explained 62.74-96.56% of the total variance of tested life-history traits, suggesting the genetic basis for differentiation of clones from both areas. Significant differences in correlations, and selection differentials and gradients of life-history traits were also found between clones from both areas, providing further evidence of genetic basis for the life-history differentiation between them. Divergence between clones from both areas and its implications for S. avenae outbreaks are discussed.

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Regiella insecticola has been found to enhance the performance of host aphids on certain plants, but its functional role in adaptation of host aphids to plants is still controversial. Here we evaluate the impacts of R. insecticola infections on vital life-history traits of Sitobion avenae (Fabricius), and their underlying genetic variation and phenotypic plasticity on three plants. It was shown that effects of R. insecticola on S. avenae’s fitness (i.e., developmental time and fecundity) were neutral on oat or wheat, but negative on rye. Infections of R. insecticola modified genetic variation that underlies S. avenae’s life-history traits. This was demonstrated by comparing life-history trait heritabilities between aphid lines with and without R. insecticola. Moreover, there were enhanced negative genetic correlations between developmental time and fecundity for R. insecticola infected lines, and structural differences in G-matrices of life-history traits for the two types of aphid lines. In R. insecticola-infected aphid lines, there were increases in plasticities for developmental times of first and second instar nymphs and for fecundity, showing novel functional roles of bacterial symbionts in plant-insect interactions. The identified effects of R. insecticola infections could have significant implications for the ecology and evolution of its host populations in natural conditions.

The apple buprestid beetle, Agrilus mali Matsumura (Coleoptera: Buprestidae), can respond to various volatiles, but the underlying mechanism of odorant perception for this insect is poorly understood. Here, we cloned A. mali's odorant-binding proteins 3 (AmalOBP3) and 8 (AmalOBP8) and characterized their expression patterns and binding profiles. Sequence and phylogenetic analyses showed that AmalOBP3 and AmalOBP8 were distributed in the classic and minus-C OBP subfamily, respectively. AmalOBP3 was specifically and abundantly expressed in antennae of both sexes. AmalOBP8 displayed high transcript levels in antennae of both sexes, abdomens of males, and wings of both sexes. Both AmalOBPs exhibited much higher expression in male antennae than in female antennae, suggesting that they could be important in perception of male-specific olfactory cues (e.g., some sex pheromones). Out of the 40 odorant ligands tested, AmalOBP3 and AmalOBP8 bound to 15 and 21 different odorants, respectively, indicating a distinct and selective binding profile for them. Both AmalOBPs seemed to have very strong binding affinity to aliphatic alcohols and aldehydes with 12 to 15 carbon atoms. Alcohols, esters, and terpenoids were more likely to be good ligands for both AmalOBPs than aldehydes and alkanes. Together with its broad expression in different tissues, strong binding with higher numbers of putative ligands for AmalOPB8 means that this protein can have more extensive functional roles in chemosensation of A. mali. Our results provide insights into the molecular basis of chemosensation in A. mali, as well as a basis for developing detection, monitoring, and management tools for this serious pest.

Recently, some studies have placed additional research focus on microRNAs (miRNAs) in a bid to discover novel therapeutic approaches for cervical cancer (CC), which is one of the most common female reproductive tract malignancies with high rates of morbidity and mortality. Hence, the aim of the present study was to evaluate the ability of miR-129-5p to influence cell angiogenesis, invasion and migration by targeting ZIC2 through the Hedgehog signaling pathway in CC. Both CC and adjacent normal tissues were extracted from 87 eligible participating patients with CC. Measurements of the levels of miR-129-5p, mRNA and protein levels of ZIC2, sonic Hedgehog (Shh), Gli1, and Gli2 and levels of CXCL1, VEGF and Ang2 were determined accordingly. An angiogenesis assay was performed to evaluate cell angiogenesis in vitro, while a scratch test and transwell assay were adopted for cell invasion and migration determination. Lastly, tumor formation within nude mice was performed in order to analyze angiogenesis and tumor growth among the nude mice in vivo. The findings revealed that upregulation of miR-129-5p resulted in the decrease in the mRNA and protein levels of ZIC2, Shh, Gli1, Gli2, as well as reduced levels of CXCL1, VEGF and Ang2. Moreover, up-regulation of miR-129-5p was determined to inhibit CC cell angiogenesis ability in vitro, in addition to the processes of cell migration, and invasion. Finally, up-regulation of miR-129-5p was observed to inhibit the tumor growth and angiogenesis ability of nude mice in vivo. The results of the present study provided evidence suggesting that overexpressed miR-129-5p prevents angiogenesis and inhibits cell migration and invasion by means of negatively targeting ZIC2 through suppression of the Hedgehog signaling pathway in CC. Thus, highlighting the promise of miR-129-5p as a novel target for treating CC is promising. ARTICLE HISTORY

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