Enhanced vitellogenesis in a whitefly via feeding on a begomovirus-infected plant.

Background: The MEAM1 (B biotype) Bemisia tabaci (Gennadius) is one of the most widespread and damaging whitefly cryptic species. Our previous studies discovered that the MEAM1 whitefly indirectly benefits from interactions with the tomato yellow leaf curl China virus (TYLCCNV) via accelerated ovarian development and increased fecundity. However, the physiological mechanism of begomoviruse-infected plants acting on the reproduction of the insect vector was unknown.

Antifeedant and insecticidal effects of mandelic acid on the brown planthopper Nilaparvata lugens Stål.

To study the effects of mandelic acid (MA) on the brown planthopper (BPH), Nilaparvata lugens, the survival rate and behaviour of BPH fed on an artificial diet with different dosages of MA was observed. The survival rate of BPH decreased with the increase of the MA concentration and feeding time. In contrast to the control, the survival rate of BPH 72 h after feeding decreased significantly.

Oosorption in the endoparasitoid, Pteromalus puparum.

Oosorption is the resorption of oocytes in the ovaries, and is usually induced by environmental stress. It has been demonstrated in some insect species, but overall the mechanisms of oosorption are poorly understood. In this study, the oosorption in the endoparasitic wasp, Pteromalus puparum L.

Identification of two species of yeast-like symbiotes in the brown planthopper, Nilaparvata lugens.

To determine the species of the yeast-like symbionts (YLS) in the brown planthoppers (BPH), Nilaparvata lugens, YLS were first isolated and purified by ultracentrifugation from the fat bodies of BPH, and then 18S rDNA and internal transcribed spacer (ITS)-5.8S rDNA sequences of YLS were amplified with the different general primers for fungi. The results showed that the two different 18S and ITS-5.

An invasive whitefly feeding on a virus-infected plant increased its egg production and realized fecundity.

Background: Plant-pathogenic begomoviruses have a complex association with their insect vectors. The interactions of begomoviruses and reproduction of their vectors are poorly understood. Bemisia tabaci is known to transmit many begomoviruses, and the spread of B.

Oogenesis and programmed cell death of nurse cells in the endoparasitoid, Pteromalus puparum.

In this study, we describe the features of oogenesis in the endoparasitoid, Pteromalus puparum, as well as the distinct type of programmed cell death of the nurse cells through conventional light and fluorescent markers for apoptosis and immunofluorescent analysis. Oogenesis in this endoparasitoid is divided into five stages, of which stages 1-2, 3-4, and 5 are corresponding to previtellogenic growth, yolk uptake, and the formation of egg envelopes, respectively. From these studies, we demonstrate two critical events, which are vitellogenin absorption and rapid transfer of nurse cell content, resulting in remarkable increase in the volume of oocytes during oogenesis in this endoparasitoid.

Venom of Pteromalus puparum (Hymenoptera: Pteromalidae) induced endocrine changes in the hemolymph of its host, Pieris rapae (Lepidoptera: Pieridae).

Pteromalus puparum is a predominant endoparasitoid wasp of Pieris rapae. Its venom is the only active factor injected into host associated with oviposition. In this report, we explored whether the venom alone from this wasp affects the endocrine system of its host or not.

Roles of ecdysteroid and juvenile hormone in vitellogenesis in an endoparasitic wasp, Pteromalus puparum (Hymenoptera: Pteromalidae).

To elucidate the endocrine regulation of vitellogenesis in an endoparastic wasp (Pteromalus puparum), the titers of ecdysteroid and juvenile hormone (JH) from the whole bodies are measured using the method of radioimmunoassay and GC-MS, and compared with the levels of vitellogenin (Vg) mRNA in the fat bodies, hemolymph Vg and ovarian vitellin (Vt), respectively. The results show that the ecdysteroid titer and fat body Vg mRNA level have a similar dynamics tendency, and the peak titer is at adult eclosion. The titer of JH III and ovarian Vt also have a similar dynamics tendency, and the peak titer is at 48h after eclosion.

A heat shock cognate 70 gene in the endoparasitoid, Pteromalus puparum, and its expression in relation to thermal stress.

The Pphsc70 (heat shock cognate 70) gene was isolated from the endoparasitoid Pteromalus puparum and then characterized. The full-length cDNA was 2204 base pair (bp) and contained a single 1968 bp ORF that encoded a polypeptide of 656 amino acids with a predicted molecular mass of 71.28 kDa.

Vitellin of Pteromalus puparum (Hymenoptera: Pteromalidae), a pupal endoparasitoid of Pieris rapae (Lepidoptera: Pieridae): Biochemical characterization, temporal patterns of production and degradation.

Vitellin (Vt) and vitellogenin (Vg) profiles were analyzed in Pteromalus puparum, a pupal endoparasitoid of Pieris rapae. Non-denaturing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analyses indicated that both native Vt and Vg were likely 370 kDa in size, consisting of two subunits of approximate 206 and 165 kDa. An indirect double antibody enzyme-linked immunosorbent assay (ELISA) for monitoring hemolymph Vg and ovarian Vt levels was developed using a monoclonal antibody and a polyclonal antibody made specially against P.

[Impact of low-level lead exposure on neural cell adhesion molecule expression of primarily cultured hippocampal neurons].

Objective: To study the impact of low-level lead exposure on neural cell adhesion molecule (NCAM) expression of primarily cultured hippocampal neurons.

Methods: Wistar rats gestated at 18th day were anaesthetized and paunched to get the pups, the hippocampi of the pups were separated and the hippocampal neurons were primarily cultured. After co-cultivated with different dosage of PbCl(2), the NCAM expression of the neurons were tested with Western blotting at different culture time.

Aluminum-induced apoptosis in cultured cortical neurons and its effect on SAPK/JNK signal transduction pathway.

Aluminum exposure and apoptotic cell death has been implicated in several neurodegenerative diseases. The mechanisms by which aluminum interacts with the nervous system are only partly understood. In this study, we used cultured cortical neurons to investigate the ability of aluminum to induce the apoptosis of neurons and to explore the role of SAPK/JNK (stress-activated protein kinase or c-jun N-terminal kinase) signal transduction pathway on the apoptosis induced by aluminum.