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The band-winged grasshopper Oedaleus asiaticus (Orthoptera: Acridoidea) is an important insect pest in north China. Chemosensory membrane proteins are believed to be crucial factors in direct interactions with odorants in the chemosensory process. However, there is much limited information on the chemosensory system in this pest. In this study, a total of 69 candidate chemosensory membrane protein genes, including 60 olfactory receptors (ORs), 6 ionotropic receptors (IRs) and 3 sensory neuron membrane proteins (SNMPs), were identified for the first time from the antennal transcriptomes of O. asiaticus. Blastp match and phylogenetic analysis demonstrated that these chemosensory membrane proteins were the closest to their orthologous species, Locusta migratoria. The qRT-PCR analysis revealed that all tested 14 OR and two SNMP genes (OasiSNMP1 and OasiSNMP2a) were strongly expressed in adult antennae, and nearly all tested genes (15/16) displayed significant differences in the expression levels between both sexes. Moreover, two IR genes (OasiIR25a and OasiIR76b) had uniquely high expression levels in the antennae, labial palps and maxillary palps, while three IR genes (OasiIR1, OasiIR2 and OasiIR3) were highly expressed in most tested tissues (heads without antennae and mouthparts, labial palps, maxillary palps, labia without labial palps, thoraxes, tarsi, and abdomens) except for antennae, labra, and wings but OasiIR5a was just faintly expressed in the antennae, labia without labial palps, labial palps, maxillary palps and abdomen. Our results provide important molecular information for further investigation on the chemoreception mechanisms in O. asiaticus.

To investigate the olfactory mechanisms in Oedaleus infernalis, one of important pests of cereals and pasture in the northern China, the whole-body transcriptome was constructed by RNA-Seq in this study. By de novo assembly, a total of 92,476 unigenes were generated in the adult sample, and 32,693 unigenes (35.35%) were successfully annotated by Blastx. Eighteen putative odorant binding proteins (OBPs) were identified, and phylogenetic analysis indicated the closest genetic relationship of eight OBPs in O. infernalis with those in its sibling species, Oedaleus asaiticus, while five OBPs in O. infernalis with those in Locusta migratoria. qRT-PCR analysis of the expression patterns of all 18 OinfOBPs in different tissues indicated that most OinfOBPs, especially OinfOBP7 and OinfOBP12, had higher expression levels in the antennae meanwhile no or faint expression in other body parts, including heads (without antennae), thoraxes, abdomens, legs, and wings, suggesting that these OBPs may play important roles in olfaction. OinfOBP2 was highly expressed only in male heads. Interestingly, only OinfOBP13 displayed high expressions in nearly all tested tissues. These two OBPs may have different physiological functions in O. infernalis. The remaining OBPs were not or weakly detected in all tested tissues. Our results provide important molecular information for further studies on chemosensory mechanisms in this pest.

Phytochemical investigation of Bulbophyllum wendlandianum (Kraenzl.) Dammer led to the isolation of twenty-three compounds 1–23 (flavanthrinin 1, coelonin 2, lusianthridin 3, densiflorol B 4, plicatol B 5, batatasin-lll 6, gigantol 7, 5-hydroxy-3,3′-dimethoxy-2-(p-hydroxybenzyl) bibenzyl 8, 2,2-dimethyl-5-hydroxy-6-carboxy-7-(2-phenylethyl) 9, tristin 10, p-hydroxybenzyl ethyl ether 11, p-hydroxybenzaldehyde 12, hydroquinone 13, coniferaldehyde 14, p-hydroxybenzyl alcohol 15, 3,4-dihydroxy benzaldehyde 16, stigmasterol 17, β-sitosterol 18, ergosterol peroxide 19, (+)pinoresinol 20, n-butyl sulfoxide 21, tridec-4E-en-l-yl acetate 22, ethyl linolate 23) including five phenanthrenes 1–5, five bibenzyls 6–10, six phenols 11–16, three sterols 17–19, one lignan 20, one n-butyl sulfoxide 21 and two fatty acids 22–23. The structures of these compounds were elucidated by spectroscopic analyses. This is the first report of isolation of compounds 1–23 from Bulbophyllum wendlandianum and compounds 8–9, 11, 13, 15–16 and 19–23 within genus Bulbophyllum. Compound 21 is a new natural product, isolated from a natural source for the first time. Furthermore, the chemotaxonomic significance of the isolates was also discussed.

Conjugated linoleic acid (CLA) is a class of positional, geometric, conjugated dienoic isomers of linoleic acid. Dietary CLA supplementation has resulted in a dramatic decrease in body fat mass in mice. However, some but not all studies in mice and humans have found that CLA promoted insulin resistance, and there were conflicting reports on the effects of CLA on peroxisomal proliferator-activated receptor-gamma (PPAR gamma) activation and expression. The objective of present study was to investigate the effect of CLA on insulin resistance and its molecular mechanisms. Fifty male Wistar rats were randomly designed to the control, high-fat and high-fat with CLA (0.75, 1.50, and 3.00 g in per 100 g diet) groups. The effect of CLA on insulin sensitivity and the mechanism of resisting diabetes by CLA were investigated by RT-PCR assay. The results showed that supplementation with CLA significantly reduced body weight gain and white fat pad weight in the rats, the levels of plasma free fatty acids (FFA), triglycerides (TGs), cholesterin (TC), leptin, insulin and blood glucose concentration in the obese rats of CLA group were also decreased compared to the rats in the high-fat group. Dietary CLA increased the mRNA expression of PPAR gamma, fatty acid binding proteins (aP2), fatty acid transporter protein (FATP), acyl-CoA synthetase (ACS) and adiponectin in the adipose tissues of obese rats. The results suggest that CLA may ameliorate insulin resistance by activating PPAR gamma, and increasing the expression of PPAR gamma target genes such as ap2, FATP, FAT, and adiponectin in the white adipose tissue.