Abstract
The genus Filobasidiella contains two species, F. neoformans and F. depauperata. The 5S ribosomal RNA genes in the two species were found to have completely different genomic arrangements. We previously reported that the 5S rRNA gene of F. neoformans, the type species of genus Filobasidiella, is located 1 kb upstream from the 18S rRNA gene within the 8.6-kb HindIII fragment of the ribosomal DNA repeat unit. The present study demonstrates the 5S rRNA gene to be absent from the rDNA repeat in F. depauperata, but is dispersed in the genome. Analysis of the nucleotide sequence from five randomly isolated 5S rDNA clones of F. depauperata showed heterogeneity at six different positions of the putative transcription region. The genus Filobasidiella is the first genus of Eumycota reported to have the 5S rRNA with two different genomic arrangements.