title: High evolutionary divergence of the 5.8S ribosomal DNA in Mimulus glaucescens (Scrophulariaceae).
abstract: Ribosomal DNA sequences for the ITS 1, 5.8S, ITS 2 and adjoining regions of the 18S and 25S were obtained from Mimulus glaucescens (Scrophulariaceae) via cloned PCR products. The spacer sequences were completely unrelated to other plant taxa, although spacer lengths were approximately the same. Interestingly, the Mimulus 5.8S sequence was much more divergent than other higher-plant rDNA sequences. Consideration of the secondary structure of the 5.8S rRNA shows that most of the changes in Mimulus are compensatory and preserve the basic secondary structure of the mature RNA molecule.
authors.affiliation: Department of Botany, University of Toronto, Ontario, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Ritland
authors.forename: N A
authors.initials: NA
authors.lastname: Straus
mesh_terms: D001483:Base Sequence; D005075:Biological Evolution; D004275:DNA, Ribosomal / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010944:Plants / Q000235:genetics*; D012335:RNA, Ribosomal / Q000235:genetics; D012340:RNA, Ribosomal, 5.8S / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid
chemical_list: D004275:DNA, Ribosomal; D012335:RNA, Ribosomal; D012340:RNA, Ribosomal, 5.8S; C065039:RNA, ribosomal, 25S