Association between SLC2A9 Genetic Variants and Risk of Hyperuricemia in a Uygur Population

This study aimed to test the effects of five single nucleotide polymorphisms within SLC2A9 on uric acid level in a special ethnic population,the Uygurs in Xinjiang,China.According to our inclusion and exclusion criteria,Uygur adults from Xinjiang constituted the study population.There were 1053 Uygur adults with hyperuricemia and 1373 normal Uygur adults who served as controls.Five single nucleotide polymorphisms within SLC2A9(rs938557,rs7679916,rs7349721,rsl3101785,and rs 13137343)were selected with the HapMap dataset and TaqMan assays.We found that,in normouricemia group,rs938557 was significantly correlated with uric acid(β=11.39±3.74,P=0.0024)adjusting for age,gender and BMI;rs7679916 and rsl3137343 were marginally associated with uric acid concentration(β=5.77±3.O9,P=0.0626;p=-5.99±3.08,P=0.0520).In the hyperuricemia group,no SNP was found to possibly influence uric acid concentration.None of these SNPs showed significant association with hyperuricemia after controlling for age,gender and BMI.There were significant or marginal correlations between certain single nucleotide polymorphisms in the SLC2A9 region and uric acid concentration in Uygur normouricemia samples.In turn,some of these single nucleotide polymorphisms in SLC2A9 may increase the risk of hyperuricemia.

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.

Silencing of odorant binding protein gene AlinOBP4 by RNAi induces declining electrophysiological responses of Adelphocoris lineolatus to six semiochemicals

Odorant binding proteins （OBPs） are believed to be important for transporting semiochemicals through the aqueous sensillar lymph to the olfactory receptor cells within the insect antennal sensilla. Here, we injected AlinOBP4-siRNA into the conjunctivum between prothorax and mesothorax of the lucerne plant bug, Adelphocoris lineolatus and evaluated the silencing of AlinOBP4 by reverse transcription polymerase chain reaction （RT-PCR） analysis, quantitative real-time PCR （qPCR） test and electroantennogram （EAG） assay. The combination of RT-PCR and qPCR analyses revealed that the levels of mes- senger RNA transcript were significantly reduced ~95% in AlinOBP4-siRNA-treated A. lineolatus males and ~75% in RNAi-treated females within 48 hours. It was found that there are different EAG responses between male and female bugs when the AlinOBP4 gene was silenced by RNAi. The EAGs of A. lineolatus to two plant volatiles, tride- canal and hexyl alcohol, were reduced 9.09% and 79.45% in RNAi-treated males, 62.08% and 62.08% in RNAi-treated females compared to the controls, separately. Antennae of RNAi-treated bugs showed significantly lower electrophysiological responses to four sex pheromone analogs, butyl butanoate, 1-hexyl butyrate, （E）-2-hexenyl butyrate and hexyl hexanoate. The EAG recordings were reduced 35.43%, 35.24%, 39.96% and 78.47% in RNAi-treated males and 64.52%, 18.13%, 36.88% and 49.52% in RNAi-treated females, respectively. The results suggested that AlinOBP4 might play dual-roles in the identifi- cation of plant volatiles and sex pheromones. It was suspected that AlinOBP4 may have different functions in odor perception between male and female A. lineolatus.

Effects of different brush border membrane vesicle isolation protocols on proteomic analysis of Cry1Ac binding proteins from the midgut of Helicoverpa armigera

Brush border membrane vesicles （BBMV） isolated from insect midguts have been widely used to study CrylA binding proteins. Sample preparation is important in two- dimensional electrophoresis （2-DE）, so to determine a suitable BBMV preparation method in Helicoverpa armigera for 2-DE, we compared three published BBMV preparation methods mostly used in sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS- PAGE）. All methods yielded similar types and numbers of binding proteins, but in different quantities. The Abdul-Rauf and Ellar protocol was the best of the three, but had limitations. Sufficient protein quantity is important for research involving limited numbers of insects, such as studies of insect resistance to Bacillus thuringiensis in the field. Consequently, we integrated the three BBMV isolation methods into a single protocol that yielded high quantities of BBMV proteins from H. armigera larval midguts, which proved suitable for 2- DE analysis.

Gene cloning and expression of aminopeptidase N and cadherin from midgut of the rice stem borer, Chilo suppressalis

The rice stem borer, Chilo suppressalis Walker is one of the most important insect pests on rice in Asia, north Africa and southern Europe. Transgenic Bt rice has been developed in the laboratory with good resistance to this pest and other Lepidopteran insects, which will provide a possible alternative tool for this pest control. The full-length cDNAs encoding an aminopeptidase N （CsAPN） and a cadherin （CsCad） were cloned from C. suppressalis. CsAPN showed common features of, and high identities to, other insect APNs in its deduced amino acid sequence. Although a full-length cDNA encoding cadherin-like protein has been reported in GenBank, the newly isolated cadherin here （CsCad） showed some differences in its amino acid sequence, especially at the 7th cadherin repeat region （CR7）, which indicated the newly isolated CsCad might be another allele. CsAPN and CsCad were successfully expressed in insect Tn cells, and the blot analysis showed these two proteins could bind Bt toxin CrylAb. The results will provide valuable information for the studies of toxin mode of action and the possible toxin resistance mechanisms in this pest.

Rice gene expression profiles responding to larval feeding of the striped stem borer at the 1st to 2nd instar stage

The objective of this study was to identify rice genes that are in response to the striped stem borer （SSB） （Chilo suppressalis Walker） feeding at the first to second larval stage. Using combined suppression subtractive hybridization （SSH） and dot blot approaches, we analyzed the induced defense genes that took place during the first 72 h of infesting intact rice （Oryza sativa L.） plants in sheath tissues with SSB larvae. By sequencing the whole SSH library, 39 expressed sequence tags involved in disease stress, insect stress or other stress responses were identified to be up-regulated by SSB larvae feeding. Among these genes, rice allene oxide cyclase （AOC）, terpene synthase （TPS） and four proteinase inhibitor （PI） genes were up-regulated by SSB larvae feeding. Real-time quantitative reverse transcription polymerase chain reaction analysis showed that four rice PI genes were already up-regulated at 6 h, and reached peaks between 6 h to 12 h. In addition, the transcription ofgene involving in jasmonate signaling pathway such as allene oxide cyclase （AOC） concerning rice early defense response to SSB feeding was activated after rice feeding by SSB for 2 h. Although the expression office terpene synthase （TPS） gene, involved in the biosynthesis ofmonoterpenes or diterpenes, was already up-regulated at 7 h, a significant increase in the expression was delayed until 12 h and reached its peak at 24 h. The present study identified six SSB-response genes and their expression patterns, which provides evidence and information to understand insect stress-response in plants.