| Autor: |
Wurtmann EJ; Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06536, USA., Wolin SL |
| Jazyk: |
angličtina |
| Zdroj: |
Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2010 Mar 02; Vol. 107 (9), pp. 4022-7. Date of Electronic Publication: 2010 Feb 16. |
| DOI: |
10.1073/pnas.1000307107 |
| Abstrakt: |
Cellular adaptations to stress often involve changes in RNA metabolism. One RNA-binding protein that has been implicated in RNA handling during environmental stress in both animal cells and prokaryotes is the Ro autoantigen. However, the function of Ro in stress conditions has been unknown. We report that a Ro protein in the radiation-resistant eubacterium Deinococcus radiodurans participates in ribosomal RNA (rRNA) degradation during growth in stationary phase, a form of starvation. Levels of the Ro ortholog Rsr increase dramatically during growth in stationary phase and the presence of Rsr confers a growth advantage. Examination of rRNA profiles reveals that Rsr, the 3' to 5' exoribonuclease polynucleotide phosphorylase (PNP) and additional nucleases are all involved in the extensive rRNA decay that occurs during starvation of this bacterium. We show that Rsr, PNP, and an Rsr-PNP complex exhibit increased sedimentation with ribosomal subunits during stationary phase. As the fractionation of PNP with ribosomal subunits is strongly enhanced in the presence of Rsr, we propose that Ro proteins function as cofactors to increase the association of exonucleases with certain substrates during stress. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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