Functional characterization of alkaline phosphatases involved alarm pheromone in the vetch aphid .

The alkaline phosphatases (ALPs) are highly promiscuous enzymes and have been extensively investigated in mammals for their medical significance, but their functional promiscuity is relatively poorly understood in insects. Here, we first identified four ALP genes (designated as ) in the vetch aphid that contained one alkaline phosphatase site, three metal-binding sites, and varied other functional sites. Phylogenetic analysis, molecular docking and the spatiotemporal expression profiling of were very different, indicating a promiscuous functionality.

Transinfected Wolbachia strains induce a complex of cytoplasmic incompatibility phenotypes: Roles of CI factor genes.

Wolbachia can modulate the reproductive development of their hosts in multiple modes, and cytoplasmic incompatibility (CI) is the most well-studied phenotype. The whitefly Bemisia tabaci is highly receptive to different Wolbachia strains: wCcep strain from the rice moth Corcyra cephalonica and wMel strain from the fruit fly Drosophila melanogaster could successfully establish and induce CI in transinfected whiteflies. Nevertheless, it is unknown what will happen when these two exogenous Wolbachia strains are co-transinfected into a new host.

Farnesyl/geranylgeranyl diphosphate synthases regulate the biosynthesis of alarm pheromone in a unique manner in the vetch aphid Megoura viciae.

Farnesyl/geranylgeranyl diphosphate synthases (FPPS/GGPPS) as the short-chain prenyltransferases catalyse the formation of the acyclic precursors (E)-FPP and (E)-GGPP for isoprenoid biosynthesis. Here, we first cloned the cDNAs encoding FPPS and GGPPS in the vetch aphid Megoura viciae (designated as MvFPPS and MvGGPPS). They had an open reading frame of 1185 and 930 bp in length, encoding 395 and 309 amino acids, with a theoretical isoelectric point of 6.

Functional characterization of two different decaprenyl diphosphate synthases in the vetch aphid Megoura viciae.

Long-chain polyprenyl diphosphate synthases play a critical role in the formation of the prenyl side-chain of ubiquinones, but up to date, their functions have scarcely been characterized in insects. Here, we first cloned the complementary DNAs encoding the subunits of decaprenyl diphosphate synthase (DPPS) in the vetch aphid Megoura viciae, an important agricultural pest insect. The results showed that there existed three DPPS subunits, designated as MvDPPS1, MvDPPS2a, and MvDPPS2b, with an open reading frame of 1218, 1275, and 1290 bp, and a theoretical isoelectric point of 7.

Identification and Behavioral Assays of Alarm Pheromone in the Vetch Aphid Megoura viciae.

Aphids are destructive pests, and alarm pheromones play a key role in their chemical ecology. Here, we conducted a detailed analysis of terpenoids in the vetch aphid, Megoura viciae, and its host plant Pisum sativum using gas chromatography/mass spectrometry. Four major components, (-)-β-pinene (49.

Transmission of the wMel Wolbachia strain is modulated by its titre and by immune genes in Drosophila melanogaster (Wolbachia density and transmission).

Wolbachia are common intracellular endosymbionts of arthropods, but the interactions between Wolbachia and arthropods are only partially understood. The fruit fly Drosophila melanogaster is a model insect for understanding Wolbachia-host interactions. Here the native wMel strain of D.

Biosynthesis of aphid alarm pheromone is modulated in response to starvation stress under regulation by the insulin, glycolysis and isoprenoid pathways.

The mechanism for biosynthesis and molecular regulation of the aphid alarm pheromone (AAP) is still a mystery. Previous studies indicated that the biosynthesis of AAP was directly affected by the terpenoid backbone biosynthesis pathway, and several pathways involved in nutritional metabolism providing the bricks for AAP biosynthesis were up-regulated in response to simulated stimulation. This suggests that AAP biosynthesis might be regulated by complex metabolic pathways.

The Intruding Wolbachia Strain from the Moth Fails to Establish Itself in the Fruit Fly Due to Immune and Exclusion Reactions.

Wolbachia is capable of regulating host reproduction, and thus of great significance in preventing the spread of insect-borne diseases and controlling pest insects. The fruit fly Drosophila melanogaster is an excellent model insect for understanding Wolbachia-host interactions. Here we artificially transferred the wCcep strain from the rice moth Corcyra cephalonica into D.

Both farnesyl diphosphate synthase genes are involved in the production of alarm pheromone in the green peach aphid Myzus persicae.

Farnesyl diphosphate synthase (FPPS) catalyzes the formation of FPP, providing the precursor for the biosynthesis of (E)-β-farnesene (EβF) in plants, but it is unknown if FPPS supplies the precursor for the biosynthesis of EβF, the major component of aphid alarm pheromone, though our previous studies support the hypothesis that EβF is synthesized by the aphid itself. Here, we used two cohorts of the green peach aphid Myzus persicae separately, reared on pepper plant and artificial diet to test the correlations among droplet emission, EβF quantity, and FPPS gene expression. It was found that the proportion of aphids emitting cornicle droplets and the quantity of EβF per milligram of aphid were both significantly different between the two cohorts, which were positively correlated with the expression of the two FPPS genes ( MpFPPS1/ 2) in M.

Host plants and obligate endosymbionts are not the sources for biosynthesis of the aphid alarm pheromone.

(E)-β-farnesene (EβF) is the major component of the alarm pheromone of many aphid species, but where EβF is synthesized in aphids is only partly understood. There are at least three most possible sources for the alarm pheromone: host plants, aphid obligate endosymbiont and aphids themselves. Here we eliminated the possibility of host plants and the obligate endosymbiont Buchnera aphidicola as the sources for EβF released by aphids.

Establishment of the cytoplasmic incompatibility-inducing Wolbachia strain wMel in an important agricultural pest insect.

The wMel Wolbachia strain was known for cytoplasmic incompatibility (CI)-induction and blocking the transmission of dengue. However, it is unknown whether it can establish and induce CI in a non-dipteran host insect. Here we artificially transferred wMel from Drosophila melanogaster into the whitefly Bemisia tabaci.

A novel Wolbachia strain from the rice moth Corcyra cephalonica induces reproductive incompatibility in the whitefly Bemisia tabaci: sequence typing combined with phenotypic evidence.

Wolbachia are a group of maternally inherited bacteria frequently found in arthropods and filarial nematodes. They have recently attracted attention for their ecological roles in manipulating host reproduction, their potential use in biological control of pest insects and medical significance. Classification of Wolbachia strains is currently solely based on molecular methods.

Bidirectional cytoplasmic incompatibility induced by cross-order transfection of Wolbachia: implications for control of the host population.

Wolbachia are widespread endosymbionts in arthropods and some nematodes. This genus of bacteria is known to manipulate host reproduction by inducing cytoplasmic incompatibility (CI). This important phenotype is implicated in the control of host populations since Wolbachia can suppress host populations through the induction of CI in a way similar to the sterile insect technique.

A type-III insect geranylgeranyl diphosphate synthase with a novel catalytic property.

Geranylgeranyl diphosphate synthase (GGPP synthase or GGPPS) is among the short-chain prenyltransferases, catalyzing the formation of the acyclic precursor GGPP for the biosynthesis of a variety of isoprenoids. GGPPSs have been extensively studied in plants, eubacteria, archaebacteria, yeast and mammals, but up to now information about an insect GGPPS is still scarce. Here we cloned the cDNA encoding an insect GGPPS from the cotton aphid (designated as AgGGPPS).

In vitro and in vivo characterization of a novel insect decaprenyl diphosphate synthase: a two-major step catalytic mechanism is proposed.

Medium- and long-chain polyprenyl diphosphate synthases (PDDSs) catalyze the synthesis of the side-chain prenyl tails of ubiquinones, which play critical physiological roles in all organisms. This class of enzymes has been extensively studied in bacteria, yeast, plants and mammals, but very little information about such enzymes is available in insects. Here we cloned the cDNAs encoding the two subunits of an aphid long-chain PDDS (designated as AgDPPS1 and AgDPPS2).

Relationship between vertebral artery hypoplasia and posterior circulation stroke in Chinese patients.

Introduction: Vertebral artery hypoplasia (VAH), which has been found in about 10 % of normal individuals, does not produce symptoms but may be associated with an increased risk of cerebral posterior circulation ischemic (PCI) stroke. The aims of this study were to determine the prevalence of VAH in Chinese patients with cerebral infarction and investigate whether VAH is an independent risk factor for PCI stroke.

Methods: The medical records of 841 Chinese stroke patients were reviewed retrospectively.

Functional analysis and molecular docking identify two active short-chain prenyltransferases in the green peach aphid, Myzus persicae.

Short-chain prenyltransferases are responsible for biosynthesis of the C(10)-C(20) precursors of a variety of isoprenoids. We previously isolated two different short-chain prenyltransferases from the green peach aphid, Myzus persicae (MpIPPS1 and MpIPPS2). In this study, the activity of the two aphid prenyltransferases was analyzed in vitro.

In silico and in vitro analyses identified three amino acid residues critical to the catalysis of two aphid farnesyl diphosphate synthase.

Farnesyl diphosphate synthase (FPPS) plays an essential role in the isoprenoid biosynthetic pathway of microbes, plants and animals. In the present study, we first cloned two FPPSs from the bird cherry-oat aphid (RpFPPS1 and RpFPPS2), and activity assay by gas chromatography-mass spectrometry showed that both RpFPPS1 and RpFPPS2 were active in vitro. They were then subjected to homology modeling and molecular docking.

A novel mutation of gap junction protein β 1 gene in X-linked Charcot-Marie-Tooth disease.

Introduction: In this study we report a novel mutation in the gap junction protein beta 1 (GJB1) gene of a Chinese X-linked Charcot-Marie-Tooth disease (CMTX1) family, which has specific electrophysiological characteristics.

Methods: Twenty members in the family were studied by clinical neurological examination and GJB1 gene mutation analysis, and 3 patients were studied electrophysiologically. The proband and his mother also underwent sural nerve biopsy.

Molecular cloning and characterization of a prenyltransferase from the cotton aphid, Aphis gossypii.

Prenyltransferases play a key role in isoprenoid biosynthesis. Here, a cDNA encoding a prenyltransferase was isolated from the cotton aphid, Aphis gossypii, which consists of 1354 nucleotides and encodes a protein of 394 amino acids (AgIPPS). Subsequent sequencing of AgIPPS genomic DNA resulted in one 3138-bp sequence.

Granulocyte-colony stimulating factor is involved in low-dose LPS-induced neuroprotection.

Granulocyte-colony stimulating factor (G-CSF) has recently been noted for neuroprotective function. Evidence has been given to indicate that G-CSF is naturally expressed in neurons and directly activates anti-apoptosis pathways. Finding out the agents inducing G-CSF production is of value for understanding the neuroprotection network in central nervous system.

Two different farnesyl diphosphate synthase genes exist in the genome of the green peach aphid, Myzus persicae.

Farnesyl diphosphate synthase (FPS; EC 2.5.1.

Prevalence of Wolbachia infection in Bemisia tabaci.

Wolbachia are obligate intracellular bacteria present in reproductive tissues of many arthropod species. It has been reported that few silverleafing populations of Bemisia tabaci were positive for Wolbachia, whereas non-silverleafing populations were more likely infected with Wolbachia and all that infect B. tabaci are Wolbachia belonging to supergroup B.

Identification and expression of odorant-binding proteins of the malaria-carrying mosquitoes Anopheles gambiae and Anopheles arabiensis.

Host preference and blood feeding are restricted to female mosquitoes. Olfaction plays a major role in host-seeking behaviour, which is likely to be associated with a subset of mosquito olfactory genes. Proteins involved in olfaction include the odorant receptors (ORs) and the odorant-binding proteins (OBPs).