title: Heterogeneity in the ribosomal family of the yeast Yarrowia lipolytica: genomic organization and segregation studies.
abstract: The cloned r-DNA units of Yarrowia lipolytica [Van Heerikhuizen et al., 39 (1985) 213-222] and their restriction fragments have been used to probe blots of genomic DNA of this yeast. Wild-type and laboratory strains were shown to contain two-to-five types of repeated units, each strain displaying a specific pattern. By comparing their restriction patterns, we could localize the differences between units within their spacer region. Tetrad analysis strongly suggested a clustered organization of each type of repeat as well as the occurrence of meiotic exchanges within the r-DNA family. Chromosome loss was induced by benomyl and allowed to map several r-DNA clusters on the same chromosome. All those results indicate that the Y. lipolytica r-DNA gene family is quite different from other yeasts.
mesh_terms: D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D004275:DNA, Ribosomal / Q000235:genetics*; D005786:Gene Expression Regulation; D005800:Genes, Fungal; D008540:Meiosis; D012335:RNA, Ribosomal / Q000235:genetics*; D011995:Recombination, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D013045:Species Specificity; D014158:Transcription, Genetic; D015003:Yeasts / Q000235:genetics*
chemical_list: D004275:DNA, Ribosomal; D012335:RNA, Ribosomal; D004262:DNA Restriction Enzymes