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Updated: Jul 19, 2026
10:59
Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events
Published on: May 13, 2019
Structural basis for processivity and single-strand specificity of RNase II
Yuhong Zuo1, Helen A Vincent, Jianwei Zhang
1Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, P.O. Box 016129, Miami, FL 33101, USA.
Molecular Cell
|September 26, 2006
Summary
The crystal structure of E. coli RNase II reveals a clamp-like assembly and a narrow channel, explaining its processivity and single-stranded RNA specificity in mRNA decay.
Area of Science:
- Biochemistry
- Structural Biology
- Molecular Biology
Background:
- RNase II is a highly processive 3'-->5' exoribonuclease.
- It belongs to the RNR family and is crucial for mRNA decay.
Purpose of the Study:
- To determine the crystal structure of E. coli RNase II.
- To elucidate the structural basis for its enzymatic activity and substrate specificity.
Main Methods:
- X-ray crystallography
- Biochemical assays
Main Results:
- The structure reveals a clamp-like assembly of three RNA-binding domains.
- A narrow, basic channel leads to the catalytic center, enclosed within the protein.
- A 7-10 nucleotide single-stranded 3' overhang is necessary for binding and hydrolysis.
Conclusions:
- The clamp and channel architecture explain RNase II's processivity.
- The structure accounts for its specificity towards single-stranded RNA.
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