Comparative analysis of 5.8 S rRNA from Ephedra kokanica Regl. (Gymnospermae) and other plant species.

5.8 S rRNA from the gymnosperm Ephedra kokanica Regl. (EMBL Data Library accession No. X15676) has been sequenced. It is 161 nucleotides long and contains three 2'-O-methylated residues--two adenosines and one guanosine. No pseudouridine have been detected. E. kokanica 5.8 S rRNA, as those from other plant species, can form a secondary structure with paired 5'- and 3'-terminal regions. 5.8 S rRNAs of seed plants differ from the moss Mnium reguicum 5.8 S rRNA in that they have longer variable 'GC-rich' hairpins with insertions in the loop region. 5.8 S rRNA of E. kokanica reveals 69 and 82% of homology with that of moss and five angiosperm species, respectively. The posttranscriptional modification pattern of plant 5.8 S rRNAs is not strictly conservative.