Structural insights into the dual activity of RNase J
2008
Abstract
The maturation and stability of RNA transcripts is controlled by a combination of endo- and exoRNases. RNase J is unique, as it combines an RNase E–like endoribonucleolytic and a 5'-to-3' exoribonucleolytic activity in a single polypeptide. The structural basis for this dual activity is unknown. Here we report the crystal structures of Thermus thermophilus RNase J and its complex with uridine 5'-monophosphate. A binding pocket coordinating the phosphate and base moieties of the nucleotide in the vicinity of the catalytic center provide a rationale for the 5'-monophosphate–dependent 5'-to-3' exoribonucleolytic activity. We show that this dependence is strict; an initial 5'-PPP transcript cannot be degraded exonucleolytically from the 5'-end. Our results suggest that RNase J might switch promptly from endo- to exonucleolytic mode on the same RNA, a property that has important implications for RNA metabolism in numerous prokaryotic organisms and plant organelles containing RNase J orthologs.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
50
References
144
Citations
NaN
KQI