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The rice leaffolder, Cnaphalocrocis medinalis Guenee, is an important lepidopteran pest of rice in Asia. Insect olfactory proteins, including olfactory receptors (ORs), ionotropic receptors (IRs), odorant-binding proteins (OBPs), chemosensory proteins (CSPs) and sensory neuron membrane proteins (SNMPs), are responsible for perception of sex pheromones and host plant volatiles, and thus regulate insect behavior. In the present study, transcriptome sequencing was conducted for C. medinalis antennae to identify genes involved in olfaction. A total of 45800 unigenes were assembled from the transcriptome dataset. Of these, 19696 (43.0%) unigenes were annotated by searching against the NCBI non-redundant database. Functional classification of these unigenes were also conducted by using the Gene Ontology (GO) and Cluster of Orthologous Groups (COG) databases. We identified 90 putative olfactory genes (including 37 novel ones): 46 ORs, 15 IRs, 12 OBPs, 15 CSPs and two SNMPs. BLASTX best hit results indicated that these genes were most identical to their respective orthologs from other lepidopteran insects. Quantitative reverse transcription-PCR (qRT-PCR) assays were performed to investigate the expression profiles of newly identified OR genes. All of the OR genes were antennae-specific or antennae-enriched. Of these, CmedOR28 and CmedOR31 were mainly expressed in male antennae, while CmedOR27 and CmedOR32 were enriched in female antennae. Our results establish a solid foundation for future functional studies of these genes.

In this study, two full-length cDNA sequences (Cmace1 and Cmace2) encoding putative acetylcholinesterases (AChEs) were cloned and characterized from the rice leaffolder, Cnaphalocrocis medinalis, an important lepidopteran rice pest in Asia. Cmace1 encodes a CmAChE1 consisting of 689 amino acid residues, while Cmace2 encodes a 639 amino acids CmAChE2. The two CmAChEs both have N-terminal signal peptides and conserved motifs including the catalytic triad, choline-binding sites, oxianion hole, acyl pocket, peripheral anionic subsite, and the characteristic FGESAG motif and conserved 14 aromatic amino acids. Phylogenetic analysis showed that Cmace1 and Cmace2 are clustered into distinct clusters that are completely diverged from each other. Reverse-transcription quantitative PCR analysis revealed that Cmace1 and Cmace2 were predominately expressed in the larval brain and at the fifth-instar larvae stage, and the transcription levels of Cmace1 were significantly higher than those of Cmace2 in all the tested samples. Recombinant CmAChE1 and CmAChE2 were heterologously expressed in baculovirus system. Using acetylthiocholine iodide (ATChI) as substrate, the Michaelis constant (Km ) values of rCmAChE1 and rCmAChE2 were 39.81 ± 6.49 and 68.29 ± 6.72 μmol/l, respectively; and the maximum velocity (Vmax ) values of the two rCmAChEs were 0.60 ± 0.02 and 0.31 ± 0.06 μmol/min/mg protein, respectively. Inhibition assay indicated that rCmAChE1 was more sensitive to the organophosphate insecticides chlorpyrifos and triazophos than rCmAChE2. This study is the first report of molecular cloning and biochemical characterization of two acetylcholinesterase genes/enzymes in C. medinalis.

Background: Heme oxygenase (HO) is a rate-limiting enzyme of endogenetic carbon monoxide (CO) that degrades heme into carbon monoxide, bilirubin, and iron. These products have important physiologic effects: bilirubin is a potent antioxidant that can act against ischemia/reperfusion injury; there is a negative correlation between the content of HO-1 and the incidence of coronary heart disease (CHD). Hypothesis: This study was undertaken to investigate the changes of HO-1 in patients with CHD. Methods: Thirty-five patients with acute myocardial infarction (AMI), 40 patients with unstable angina pectoris (UAP, diagnosed by coronary angiography), and 30 patients with stable angina pectoris (AP, diagnosed by coronary angiography) were selected for the study; another 30 patients with normal coronary artery (diagnosed by coronary angiography) were selected as controls. The levels of HO-1 protein expression in monocyte and lymphocyte in the subjects were tested by immunohistochemistry and western blot. Computer picture analyzing systems were also used to measure the levels of HO-1 protein expression. Results: Heme oxygenase-1 protein is located in cell plasma. The levels of HO-1 protein expression in patients with CHD were significantly higher than in those without CHD (p