Intermediate States of Ribonuclease III in Complex with Double-Stranded RNA

Journal Article · Mon Jul 19 04:00:00 EDT 2010 · Structure

OSTI ID:1008621

Gan, Jianhua; Tropea, Joseph E; Austin, Brian P; Court, Donald L; Waugh, David S; Ji, Xinhua ^[1]

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1. NIH

Bacterial ribonuclease III (RNase III) can affect RNA structure and gene expression in either of two ways: as a processing enzyme that cleaves double-stranded (ds) RNA, or as a binding protein that binds but does not cleave dsRNA. We previously proposed a model of the catalytic complex of RNase III with dsRNA based on three crystal structures, including the endonuclease domain of RNase III with and without bound metal ions and a dsRNA binding protein complexed with dsRNA. We also reported a noncatalytic assembly observed in the crystal structure of an RNase III mutant, which binds but does not cleave dsRNA, complexed with dsRNA. We hypothesize that the RNase III {center_dot} dsRNA complex can exist in two functional forms, a catalytic complex and a noncatalytic assembly, and that in between the two forms there may be intermediate states. Here, we present four crystal structures of RNase III complexed with dsRNA, representing possible intermediates.

• Research Organization: Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, IL (US)
• Sponsoring Organization: USDOE
• OSTI ID: 1008621
• Journal Information: Structure, Journal Name: Structure Journal Issue: (10) ; 10, 2005 Vol. 13
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL STRUCTURE
ENDONUCLEASES
ENZYMES
FUNCTIONALS
GENES
PROCESSING
PROTEINS
RNA
RNA-ASE