Functional Analysis of the Kinome of the Wheat Scab Fungus Fusarium graminearum

As in other eukaryotes, protein kinases play major regulatory roles in filamentous fungi. Although the genomes of many plant pathogenic fungi have been sequenced, systematic characterization of their kinomes has not been reported. The wheat scab fungus Fusarium graminearum has 116 protein kinases (PK) genes. Although twenty of them appeared to be essential, we generated deletion mutants for the other 96 PK genes, including 12 orthologs of essential genes in yeast. All of the PK mutants were assayed for changes in 17 phenotypes, including growth, conidiation, pathogenesis, stress responses, and sexual reproduction. Overall, deletion of 64 PK genes resulted in at least one of the phenotypes examined, including three mutants blocked in conidiation and five mutants with increased tolerance to hyperosmotic stress. In total, 42 PK mutants were significantly reduced in virulence or non-pathogenic, including mutants deleted of key components of the cAMP signaling and three MAPK pathways. A number of these PK genes, including Fg03146 and Fg04770 that are unique to filamentous fungi, are dispensable for hyphal growth and likely encode novel fungal virulence factors. Ascospores play a critical role in the initiation of wheat scab. Twenty-six PK mutants were blocked in perithecia formation or aborted in ascosporogenesis. Additional 19 mutants were defective in ascospore release or morphology. Interestingly, F. graminearum contains two aurora kinase genes with distinct functions, which has not been reported in fungi. In addition, we used the interlog approach to predict the PK-PK and PK-protein interaction networks of F. graminearum. Several predicted interactions were verified with yeast two-hybrid or co-immunoprecipitation assays. To our knowledge, this is the first functional characterization of the kinome in plant pathogenic fungi. Protein kinase genes important for various aspects of growth, developmental, and infection processes in F. graminearum were identified in this study

Description de la larve et de la pupe de Cheilosia vulpina Meigen (1922), mineuse de racine d'Artichaut (Cynara scolymus L.) en Bretagne.

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Mise en evidence d'une diapause nymphale chez Cheilosia vulpina Meigen (Diptere, Syrphides) ravageur de l'artichaut.

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Syrphid larvae (Diptera: Syrphidae) mining the roots of artichoke (Cynara scolymus L.) in Brittany

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Inventaire des Dipteres pourquoi? comment?

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Les Dolichopodidés et les Syrphidés des îles de la "réserve de Biosphère" d'Iroise (Finistère, France) : premier inventaire (Diptera)

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Un nouveau ravageur de l'artichaut: Un diptere, Cheilosia vulpina.

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Régulation biologique des mauvaises herbes: Etude du rôle des insectes dans la régulation de Rumex obstusifolius L. sur des prairies temporaires agrobiologiques dans le bassin de Rennes.

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Development of a computerised system for animal health management as a part of an eradication program of Aujeszky's disease

Brittany is the main pig production area in France. About 14 million fatteners are produced a year in this province. There are 9200 farms holding about 690 000 sows. Farrow-to-finish herds are prevalent, representing half of the farms and 70% of the production. More than 4 million piglets are transported per year. An eradication program for Aujeszky's disease is currently in action. The key points of this program are: (1) yearly general serological screening; (2) quarterly blood testing of nucleus and multipliers herds (these herds cannot sell boars and gilts if they are not AD free); (3) compulsory vaccination; (4) a special authorisation needed to move piglets out of non-AD free farms is given by veterinary services. This program involves many organisations. There are four Regional State Veterinary Services (DSV) which are the governmental services at the department level. They manage the eradication plan. Four Departmental Stockfarming Establishments (EDE) are the professional farming bodies with statutory responsibility for identifying stock farms. Twenty-one producer groups (gathering 90% of the farmers and 98% of the fatteners), federated into a union - the UGPVB - organise most transport of piglets, gilts and fatteners. Their importance is a strong characteristic of pig production in Brittany and a key point to understanding the way INFOPORC was built. In addition there are 8 testing laboratories which perform all the serological analyses and 300 field veterinarians. To perform the eradication plan, all the organisations involved have to share information. In particular, a single register of all pig farms, classifying farms according to their health status, identifying animal movement, and producing trend charts and maps is needed. The aim of the INFOPORC information system is to manage all this information, quickly and reliably. The "Association Régionale Interprofessionnelle Porcine" (ARIP) has undertaken, under the general supervision of the French Ministry of Agriculture, Fisheries and Food, to devise, develop and introduce this pilot computerised network for animal health management of pigs. Role of each partner within INFOPORC: The architecture is based on the general principle of a central site and distributed applications. With the exception of the veterinarians, all the active participants connected to the network have a dedicated microcomputer connected to the central. The reference site for the system is the "INFOPORC Node", which is situated in the premises of a specialised computer centre called ARSOE. This site manages the INFOPORC reference database in which the following data are stored: basic data for the INFOPORC system (contact people, livestock farms, etc.), historical records of events managed in INFOPORC (transport, health situation), and data shared or exchanged between different connected computers. All exchanges of information between the different applications integrated into the system are managed by the INFOPORC Node. Each distributed application is linked to the central site by a daily file-exchange procedure. This approach is suited to allow gradual extension of the system. The status of Aujeszky's disease, managed by the DSVs, is transmitted to the producer's groups before transporting pigs in order to check the status of the farms of origin and requirements concerning the introduction of pigs into the farms at destination. After the transport, data entered by the producers groups are automatically transmitted to DSVs. It is therefore possible at any time to search: (1) for the origin or destination of pigs from a given farm (or a given area); (2) for a complete list of transport operations by a given operator; (3) For all herds in a given radius using a Geographical Information System linked to the database. INFOPORC has been in action in the field since May 1998. At present, all movements of piglets (from breeder to finisher or intermediary) are recorded. There are now about 2000 transports registered per month for a total of $400\, 000$ piglets. Historical records of all movements are kept for 5 years. Even if computers will never eradicate any virus, INFOPORC is a useful tool, probably an essential one, for the management of an eradication scheme within a high density pig production area like Brittany. Moreover, such a system will be useful not only for Aujeszky's disease, but also to prevent Classical Swine Fever and other epidemics and to manage Integrated Quality Systems

A heat-sensitive Osh protein controls PI4P polarity

Background Phosphoinositide lipids provide spatial landmarks during polarized cell growth and migration. Yet how phosphoinositide gradients are oriented in response to extracellular cues and environmental conditions is not well understood. Here, we elucidate an unexpected mode of phosphatidylinositol 4-phosphate (PI4P) regulation in the control of polarized secretion. Results We show that PI4P is highly enriched at the plasma membrane of growing daughter cells in budding yeast where polarized secretion occurs. However, upon heat stress conditions that redirect secretory traffic, PI4P rapidly increases at the plasma membrane in mother cells resulting in a more uniform PI4P distribution. Precise control of PI4P distribution is mediated through the Osh (oxysterol-binding protein homology) proteins that bind and present PI4P to a phosphoinositide phosphatase. Interestingly, Osh3 undergoes a phase transition upon heat stress conditions, resulting in intracellular aggregates and reduced cortical localization. Both the Osh3 GOLD and ORD domains are sufficient to form heat stress-induced aggregates, indicating that Osh3 is highly tuned to heat stress conditions. Upon loss of Osh3 function, the polarized distribution of both PI4P and the exocyst component Exo70 are impaired. Thus, an intrinsically heat stress-sensitive PI4P regulatory protein controls the spatial distribution of phosphoinositide lipid metabolism to direct secretory trafficking as needed. Conclusions Our results suggest that control of PI4P metabolism by Osh proteins is a key determinant in the control of polarized growth and secretion