Two international trainings on the in vitro culture of AM fungi are offered by the CESAMM/GINCO teams.

For more information, visit: International trainings website

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PhD positions (2005-05-12)

PhD 1 : The effects of SBI fungicides on the AM fungal symbiosis

This research will be carried out at the UNIVERSITE CATHOLIQUE DE LOUVAIN (UCL) established in Belgium (contact person Stéphane Declerck ? declerck@mbla.ucl.ac.be).

Fungicides which act through the inhibition of the post-squalene sterol pathway can be divided into several classes according to the enzymatic targets : C14-demethylase inhibitors (DMI), D isomerase inhibitors, D reductase inhibitors and D sterol methyltransferase inhibitors. We will select one sample from every of these classes of SBI and test all of them on the AM fungal species sampled in agricultural systems managed with pesticides, in undisturbed ecosystems and in polluted ecosystems. Two complementary approaches will be explored. Firstly, the impact of these chemicals on the development of AM fungi will be evaluated by growing the AM fungi on media containing SBI. This will allow to evaluate if the germination ability of spores, root colonisation rate and sporulation potential are affected. The tested molecules with no or very little effect and the SBI concentrations used with no damage on AM fungi will be determined. Secondly, the impact of these SBI on the survival and effectiveness of AM fungi will be estimated by adding the fungicides to well developed fungal ROC. The use of in vitro systems in which roots are physically separated from the hyphae, with an essential marked nutrient (32P) added to the hyphal compartment will allow to test the efficiency of the AM fungi to transfer an essential nutrient in the presence of fungicides. Both these approaches will allow to know the impact of these toxicants on survival and efficiency of well established symbiotic associations.

PhD 2: Effects of SBI fungicides on the changes in sterol composition of AM fungi and mechanisms of fungicides action and fungal sterol metabolism

This research will be carried out at the UNIVERSITE DU LITTORAL ? COTE D?OPALE (ULCO) established in France (contact person Anne Grandmougin-Ferjani ? grand@opale.univ-littoral.fr).

The AM fungi which are grown for the first part of this program can be use for the analysis of the sterol content. Generally, SBI lead to a decrease in the amount of the major sterols and the accumulation of precursors or abnormal sterols. These modifications may induce serious damages for fungus since sterols are essential for the cell where they play different functions : a bulk membrane role, for which large amounts of sterols are needed and involvement in cell proliferation (called sparking hormonal) for which the quantities needed appear to be much smaller. The study of sterol content could give information on the mechanism of fungitoxicity of these fungicides never shown for AM fungi so far. Furthermore, by using high concentrations of SBI, it is possible to block enzymatic steps. This may allow us to propose sterol biosynthesis pathway in AM fungi, until now incomplete.

PhD 3: Effects of SBI fungicides on AM fungi gene regulation

This research will be carried out in UNIVERSITA? DEGLI STUDI DI TORINO (UNITO) established in Italy (contact person Luisa Lanfranco - luisa.lanfranco@unito.it).

The research will focus on gene expression by means of targeted and untargeted molecular approaches. In detail, the expression of genes involved in sterol biosynthesis will be investigated as well as the global changes in gene expression after treatment with SBI. Yeast and fungal genes encoding for sterol biosynthesis enzymes have been cloned and corresponding sequences are available in gene banks. This information will be used to design degenerate oligonucleotides for PCR amplification or as source of heterologous probes for the screening of gelastnameic or cDNA libraries. Regulation of gene expression will be evaluated after treatment with SBI fungicides of fungal material under root organ culture (ROC) and/or in pot co-cultures. Large scale-expression analysis using cDNA macroarrays, cDNA-AFLP or SSH libraries technique will be carried out to identify genes regulated by SBI fungicides.The three PhD students will have the opportunity to spend periods in all the institutions involved in the project to learn techniques and conduct complementary experiments to answer the questions of FUNGIMYC.

The PhD studentships will be available from November 2005 for a period of three years.

Criteria for recruitment of young fellows will be
· High grade academic curriculum vitae in most appropriate discipline
· interest and motivation in conducting the research activity and accomplishment of PhD
· interest in mobility
· curiosity
· agreeable personality and integration capacity within teams

The young fellows should send their Curriculum vitae to the contact person of the PhD subject of interest and to Prof. S. Declerck (declerck@mbla.ucl.ac.be) as coordinator of the proposal.

Deadline for submission of Curriculum vitae : 15/06/2005

Start date of PhD programme :01/10/2005

Duration : 36 months

Yearly living allowance : approxim. 31 000 euro.

Declerck