Mitochondrial RNase P RNAs in ascomycete fungi: lineage-specific variations in RNA secondary structure.
RNA
; 9(9): 1073-83, 2003 Sep.
Article
en En
| MEDLINE
| ID: mdl-12923256
ABSTRACT
The RNA subunit of mitochondrial RNase P (mtP-RNA) is encoded by a mitochondrial gene (rnpB) in several ascomycete fungi and in the protists Reclinomonas americana and Nephroselmis olivacea. By searching for universally conserved structural elements, we have identified previously unknown rnpB genes in the mitochondrial DNAs (mtDNAs) of two fission yeasts, Schizosaccharomyces pombe and Schizosaccharomyces octosporus; in the budding yeast Pichia canadensis; and in the archiascomycete Taphrina deformans. The expression of mtP-RNAs of the predicted size was experimentally confirmed in the two fission yeasts, and their precise 5' and 3' ends were determined by sequencing of cDNAs generated from circularized mtP-RNAs. Comparative RNA secondary structure modeling shows that in contrast to mtP-RNAs of the two protists R. americana and N. olivacea, those of ascomycete fungi all have highly reduced secondary structures. In certain budding yeasts, such as Saccharomycopsis fibuligera, we find only the two most conserved pairings, P1 and P4. A P18 pairing is conserved in Saccharomyces cerevisiae and its close relatives, whereas nearly half of the minimum bacterial consensus structure is retained in the RNAs of fission yeasts, Aspergillus nidulans and Taphrina deformans. The evolutionary implications of the reduction of mtP-RNA structures in ascomycetes will be discussed.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Ascomicetos
/
ARN
/
ARN Catalítico
/
Endorribonucleasas
/
Mitocondrias
/
Conformación de Ácido Nucleico
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
RNA
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2003
Tipo del documento:
Article
País de afiliación:
Canadá