Expressed sequences from the basidiomycetous tree pathogen Heterobasidion annosum during early infection of scots pine.
The pattern of gene expression of the basidiomycete Heterobasidion annosum, causal agent of the root rot of conifers, was analysed during its interaction with pine roots. A complementary DNA (cDNA) library was constructed from total RNA extracted from H. annosum mycelia challenged with Scots pine seedling roots for 6 and 72h. Single pass sequencing of 1148 randomly selected cDNA clones resulted in 923 expressed sequence tags (ESTs). Contig analysis and sequence comparisons identified 318 unigene sequences, of which 62 were repeatedly sampled. A putative cellular function was assigned to 223 contigs (70%) that showed a moderate to high homology to protein sequences from public databases. Variations in expression levels during the infection process were monitored on a set of 96 unigenes by reverse northern using dot hybridisation. Seven unigenes (7%) were shown to be either up (4) or down (3) regulated during interaction of the fungus with pine roots. Fungal genes differentially expressed during contact with roots include genes encoding mitochondrial proteins, a cytochrome P450 and a vacuolar ATP synthase.
Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, Box 7026, SE-750 07, Uppsala, Sweden. magnus.karlsson@mykopat.slu.se
Magnus
M
Karlsson
Ake
A
Olson
Jan
J
Stenlid
D001487:Basidiomycota / Q000737:chemistry / Q000201:enzymology / Q000235:genetics*; D015152:Blotting, Northern; D020224:Expressed Sequence Tags; D015966:Gene Expression Regulation, Fungal; D015723:Gene Library; D005800:Genes, Fungal; D014644:Genetic Variation; D024101:Mitochondrial Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D028223:Pinus / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology*; D018517:Plant Roots / Q000382:microbiology; D025341:Principal Component Analysis; D017385:Sequence Homology; D013482:Superoxide Dismutase / Q000235:genetics
D024101:Mitochondrial Proteins; D013482:Superoxide Dismutase