Characterization of the gene encoding pisatin demethylase (FoPDA1) in Fusarium oxysporum.

The pea pathogen Fusarium oxysporum f. sp. pisi is able to detoxify pisatin produced as a defense response by pea, and the gene encoding this detoxification mechanism, FoPDA1, was 82% identical to the cytochrome P450 pisatin demethylase PDA1 gene in Nectria haematococca.

An analysis of the phylogenetic distribution of the pea pathogenicity genes of Nectria haematococca MPVI supports the hypothesis of their origin by horizontal transfer and uncovers a potentially new pathogen of garden pea: Neocosmospora boniensis.

The filamentous fungus Nectria haematococca mating population VI (MPVI) contains a cluster of genes required to cause disease on pea. This cluster of pea pathogenicity genes (the PEP cluster) is located on a supernumerary chromosome that is dispensable for normal growth in culture. The genes in the PEP cluster have a different G+C content and codon usage compared with the genes located on the other chromosomes and a non-homogeneous distribution within the species.

Histone H1 Is required for proper regulation of pyruvate decarboxylase gene expression in Neurospora crassa.

We show that Neurospora crassa has a single histone H1 gene, hH1, which encodes a typical linker histone with highly basic N- and C-terminal tails and a central globular domain. A green fluorescent protein-tagged histone H1 chimeric protein was localized exclusively to nuclei. Mutation of hH1 by repeat-induced point mutation (RIP) did not result in detectable defects in morphology, DNA methylation, mutagen sensitivity, DNA repair, fertility, RIP, chromosome pairing, or chromosome segregation.

Distribution of the pea pathogenicity ( PEP) genes in the fungus Nectria haematococca mating population VI.

Previous studies identified a cluster of six genes that are expressed in the fungus Nectria haematococca mating population VI during infection of pea. Four of these genes were shown to contribute to pathogenicity on pea and were called PEP genes for pea pathogenicity. The cluster is located on a "conditionally dispensable" (CD) chromosome and has features similar to bacterial pathogenicity islands.