Synthesis of large rRNAs by RNA polymerase II in mutants of Saccharomyces cerevisiae defective in RNA polymerase I.
AUTOR(ES)
Nogi, Y
RESUMO
The 35S rRNA gene of the yeast Saccharomyces cerevisiae was fused to the GAL7 promoter. This hybrid gene, when present on a multicopy plasmid and induced by galactose, suppressed the growth defects of a temperature-sensitive RNA polymerase I (pol I) mutant and those of a mutant in which the gene for the second largest subunit of pol I was deleted. Analysis of pulse-labeled RNA directly demonstrated that rRNA synthesis in this deletion mutant is from the GAL7 promoter. These experiments show that the sole essential function of pol I is the transcription of the rRNA genes, that pol I is not absolutely required for the synthesis of rRNA and ribosomes or cell growth if 35S rRNA synthesis is achieved by some other means, and that the tandemly repeated structure of the chromosomal rRNA genes is also not absolutely required for the synthesis of rRNA and ribosomes.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=51573Documentos Relacionados
- Structural alterations of the nucleolus in mutants of Saccharomyces cerevisiae defective in RNA polymerase I.
- Recovery of RNA polymerase II synthesis following DNA damage in mutants of Saccharomyces cerevisiae defective in nucleotide excision repair.
- A polymerase switch in the synthesis of rRNA in Saccharomyces cerevisiae.
- Temperature sensitive nop2 alleles defective in synthesis of 25S rRNA and large ribosomal subunits in Saccharomyces cerevisiae
- Isolation and characterization of temperature-sensitive RNA polymerase II mutants of Saccharomyces cerevisiae.
