Heterologous array analysis in Heterobasidion: Hybridisation of cDNA arrays with probe from mycelium of S, P or F-types

Because of the close relatedness between three species of Heterobasidion annosum (P-type), Heterobasidion parviporum (S-type) and Heterobasidion abietinum (F-type), we investigated the possible use of arrays from one species for studies of gene expression in the other. Clones containing partial cDNAs from 94 identifiable genes expressed during spore germination and differentiation in H. parviporum were printed manually in six replications on nylon membranes. The membrane was hybridized with chemifluorescent labelled cDNA from actively growing mycelia of H. parviporum, H. annosum or H. abietinum, cultivated on a non-selective substrate. Product–moment correlation coefficient varied between 0.81 and 0.49. Due to the level of correlation, in the gene expression among the intersterility groups, we concluded that the cDNA array of one can be used to study gene expression in the others.