De novo analysis of the transcriptome of Pratylenchus zeae to identify transcripts for proteins required for structural integrity, sensation, locomotion and parasitism

The root lesion nematode Pratylenchus zeae, a migratory endoparasite, is an economically important pest of major crop plants (e.g. cereals, sugarcane). It enters host roots, migrates through root tissues and feeds from cortical cells, and defends itself against biotic and abiotic stresses in the soil and in host tissues. We report de novo sequencing of the P. zeae transcriptome using 454 FLX, and the identification of putative transcripts encoding proteins required for movement, response to stimuli, feeding and parasitism. Sequencing generated 347 443 good quality reads which were assembled into 10 163 contigs and 139 104 singletons: 65% of contigs and 28% of singletons matched sequences of free-living and parasitic nematodes. Three-quarters of the annotated transcripts were common to reference nematodes, mainly representing genes encoding proteins for structural integrity and fundamental biochemical processes. Over 15 000 transcripts were similar to Caenorhabditis elegans genes encoding proteins with roles in mechanical and neural control of movement, responses to chemicals, mechanical and thermal stresses. Notably, 766 transcripts matched parasitism genes employed by both migratory and sedentary endoparasites in host interactions, three of which hybridized to the gland cell region, suggesting that they might be secreted. Conversely, transcripts for effectors reported to be involved in feeding site formation by sedentary endoparasites were conspicuously absent. Transcripts similar to those encoding some secretory-excretory products at the host interface of Brugia malayi, the secretome of Meloidogyne incognita and products of gland cells of Heterodera glycines were also identified. This P. zeae transcriptome provides new information for genome annotation and functional analysis of possible targets for control of pratylenchid nematodes

Konvergenzen und Divergenzen zwischen dem ost- und westdeutschen Management: Ergebnisse einer Befragung von Leitern mittelständischer Industrieunternehmen in Ost- und Westdeutschland

Im Kontext des übergreifenden Forschungsprogramms 'Gesellschaftliche Entwicklungen nach dem Systemumbruch. Diskontinuität, Tradition und Strukturbildung' präsentieren die Autoren in ihrem Beitrag empirische Ergebnisse zu dem Teilprojekt 'Generationswechsel im Management - Persistenz oder Wandel der Managementstrategien in Ost- und Westdeutschland'. Bei der durchgeführten Erhebung handelt es sich um eine computerunterstützte Telefonbefragung (CATI) von 799 Personen mit einem standardisierten Fragebogen. Der Untersuchungsgegenstand ist eingebettet bzw. geprägt durch die Herausforderungen, die im Zuge globaler Entwicklungen zu erwarten sind, sowie durch den Wandel der ostdeutschen Industrie, der immer noch durch Langfristfolgen der Wendezeit beeinflusst wird. Dem gemäß konzentriert sich die Analyse auf zwei thematische Schwerpunkte: (1) die Ost/West-Unterschiede in Form eines Vergleichs zwischen dem ostdeutschen und westdeutschen Management sowie zwischen ost- und westdeutschen Betrieben; (2) die Generations- bzw. Altersunterschiede zwischen einzelnen Geburtskohorten. Die Ausführungen gliedern sich in die folgenden Aspekte: (1) Struktur der mittelständischen Industrieunternehmen, (2) Veränderungen der Unternehmensfinanzierung im Mittelstand, (3) soziale Struktur des mittelständischen Topmanagements, (3) Arbeits- und Sozialbeziehungen zwischen Management und Belegschaft, (4) gesellschaftspolitische Orientierungen der Unternehmensleiter, (5) Leitbilder von Managementstrategien der betrieblichen Restrukturierung sowie (6) Führungswechsel und Unternehmensübergabe. Im Schlusskapitel werden die präsentierten Ergebnisse über Ähnlichkeiten und Unterschiede zwischen Geburtskohorten sowie der ost- und westdeutschen Managementkulturen zu Aussagen über Entwicklungstrends und Wandlungstendenzen verdichtet. Im Wesentlichen sprechen die Ergebnisse für die Kontinuität eines eigenständigen 'westdeutschen' Managementmodells, welches auch nach Ostdeutschland 'ausstrahlt'. Welchen Verlauf der Einfluss von Akteuren und institutionellen Rahmenbedingungen auf die Entwicklung von Divergenzen und Konvergenzen zwischen ostdeutschem und westdeutschem Management nehmen wird, kann erst durch den Einbezug weiterer Panelwellen der Untersuchung deutlich herausgearbeitet werden

Gene silencing in root lesion nematodes (Pratylenchus spp.) significantly reduces reproduction in a plant host

Root lesion nematodes (RLNs, Pratylenchus species) are a group of economically important migratory endoparasitic plant pathogens that attack host roots of major crops such as wheat and sugarcane, and can reduce crop yields by 7-15%. Pratylenchus thornei and Pratylenchus zeae were treated with double stranded RNA (dsRNA) to study gene silencing, (RNA interference, RNAi), as a potential strategy for their control. Mixed stages of nematodes of both species ingested dsRNA when incubated in a basic soaking solution in the presence of the neurostimulant octopamine. Incubation for up to 16. h in soaking solutions containing 10-50. mM octopamine, 0.1-1.0. mg/mL FITC, and 0.5-6. mM spermidine did not affect vitality. Spermidine phosphate salt hexahydrate rather than spermidine or spermidine trihydrochloride increased uptake of FITC by nematodes, and this resulted in more effective gene silencing. Silencing pat-10 and unc-87 genes of P. thornei and P. zeae resulted in paralysis and uncoordinated movements in both species, although to a higher degree in P. thornei. There was also a greater reduction in transcript of both genes in P. thornei indicating that it may be more susceptible to RNAi. For P. thornei treated with dsRNA of pat-10 and unc-87 there was a significant reduction (77-81%) in nematode reproduction on carrot mini discs over a 5. week period. The results show that RLNs are clearly amenable to gene silencing, and that in planta delivery of dsRNA to target genes in these nematodes should confer host resistance. Moreover, for the two genes, dsRNA derived from either nematode species silenced the corresponding gene in both species. This implies cross-species control of nematodes via RNAi is possible

Novel molecular diagnostic frame work for plant parasitic nematode pest of plant biosecurity concern-better and faster than classical taxonomy?

Phyto-nematodes are one of the four most important agricultural pests worldwide. The annual losses in agricultural production from nematode infection is about USD$120 billion. Although phyto-nematodes cannot move more than a metre per year, human activities have lead to the dispersal of these major pests around the world, and the transportation of infected plant materials from one continent to another can put Australian agriculture at risk. "Plant Biosecurity" requires cutting edge molecular techniques to identify biosecurity pathogens. The aim of this project is to develop new protocols for early detection of exotic phyto-nematodes: this will benefit Australia and help safeguard its borders. A requirement is to reduce the time taken for nematode identification so that pest incursions can be detected and controlled early. Most nematode identification has been done by classical taxonomy. However, this requires trained taxonomists familiar with nematode morphology, and identification is time consuming for an unknown nematode. More recent molecular techniques of nematode diagnostics have shown promising results for nematode identification. Molecular diagnostics has proved to be reliable and rapid compared to classical approaches. In this project, work is being undertaken to compare DNA-based, protein-based and novel methods of nematode identification. So far, DNA and protein diagnostic methods have been developed for a range of root lesion and cyst nematodes. Characteristic sequences of ITS regions have been generated and phylogenetic relations of these nematodes studied. Similarly protein biomarkers have been established that can be used-both to identify species and genera of these nematodes. Although plant nematodes can only move short distances on their own, they have been transported around the world effectively by human activities. The outcome of this project will help reduce entry of exotic nematodes into Australia, and so help reduce potential crop tosses

Application of gene silencing for nematode control

Root lesion nematodes (Pratylenchus spp., RLNs) are major pests of most crops, and reduce yields of wheat in Western Australia by up to 15%, with Australia-wide losses of more than $36 million per annum. The aim of this project is to investigate the use of RNA interference (RNAi) as an approach to confer resistance to RLNs. RNAi is a well established technology that can be used to silence specific genes in animals and plants. Exposure to artificially introduced double-stranded RNA (dsRNA) leads to the silencing of endogenous genes with homologous sequence. RNAi can silence genes in Caenorhabditis elegans, and some success has been reported in root-knot nematodes. There is no evidence yet that RNAi works for RLNs. RLNs are migratory endoparasitic nematodes, and so mobility is an important aspect of parasitism. In this study, we are investigating genes involved in locomotion in RLNs via RNAi. We have shown that P.thornei and P.zeae are indeed amenable to RNAi. Exposure to dsRNA for locomotion specific genes by 14 hours soaking in medium containing M9 buffer with 50 mM octopamine, 3 mM spermidine and 0.05% gelatin led to locomotion impairment in both of these species. In addition, dsRNA originating from P.thornei also led to abnormalities in the closely related species P.zeae and vice versa, indicating that inter-species gene knockdown is possible. The outcome of this study is economically significant as no reported natural resistance genes have broad effectiveness against RLNs. Bioengineered crops expressing dsRNA that silence essential target genes to interrupt the parasitic process represents a potential approach to develop novel, broadly applicable and durable RLN-resistance in crop plants

Selective induction of alternatively spliced FynT isoform by TNF facilitates persistent inflammatory responses in astrocytes

10.1038/srep43651Scientific Reports74365

Andrographolide induces Nrf2 and heme oxygenase 1 in astrocytes by activating p38 MAPK and ERK

10.1186/s12974-016-0723-3Journal of Neuroinflammation13125

12th yahya cohen memorial lecture - The cellular and molecular basis of radiation-induced sensori-neural hearing loss

Annals of the Academy of Medicine Singapore38191-94AAMS

Andrographolide attenuates LPS-stimulated up-regulation of C-C and C-X-C motif chemokines in rodent cortex and primary astrocytes

10.1186/s12974-016-0498-6Journal of Neuroinflammation1313