Evidence for ribosomes involved in splicing of yeast mitochondrial transcripts.
AUTOR(ES)
Schmelzer, C
RESUMO
We have investigated the processing of transcripts of the split gene COB in yeast mitochondrial DNA from cells whose mitochondrial translation was blocked by chloramphenicol for several generations of cell growth. First analysis of transcripts by electrophoresis and RNA/DNA-hybridization clearly showed that cell growth in the presence of CAP leads to an inhibition of processing yielding an increasing amount of splicing intermediates of the COB transcript and decreasing amounts of the 18S mRNA coding for apocytochrome b. This observation is in accordance with the now widely favoured idea that mitochondrial proteins are involved in splicing of COB transcripts and that their reduction should hamper processing and - therefore - lead to an accumulation of pre-mRNAs. However, further information obtained by pulse-labeling of pre-mRNA in vivo in the presence of CAP for various times shows that even 30 minutes after addition of CAP a reduction of the processing rate is obtained. Based on these findings we conclude that maturation of mtRNAs is not only dependent on mitochondrial proteins, but also on a more direct interaction of the translation machinery and RNA processing whose nature is so far unknown.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=326154Documentos Relacionados
- A mitochondrial intergenic mutation affecting processing of specific yeast mitochondrial transcripts.
- Effect of intron size on splicing efficiency in retroviral transcripts.
- Alternative splicing dictates translational start in Epstein-Barr virus transcripts.
- Characterization of Mitochondrial Ribosomes from Yeast
- Construction of a yeast strain devoid of mitochondrial introns and its use to screen nuclear genes involved in mitochondrial splicing.