3O8C

Visualizing ATP-dependent RNA Translocation by the NS3 Helicase from HCV

Summary for 3O8C

• Entry DOI: 10.2210/pdb3o8c/pdb
• Related: 1CU1 3O8B 3O8D 3O8R
• Descriptor: HCV NS3 protease/helicase, RNA (5'-R(P*UP*(5BU)P*UP*UP*UP*U)-3'), ZINC ION, ... (5 entities in total)
• Functional Keywords: helicase, ntpase, hcv, rna, translocation, protease/ntpase/helicase, hydrolase-rna complex, hydrolase/rna
• Biological source: Hepatitis C virus subtype 1b; More
• Total number of polymer chains: 3
• Total formula weight: 143932.66

Authors

Appleby, T.C.,Somoza, J.R. (deposition date: 2010-08-02, release date: 2011-01-05, Last modification date: 2023-09-06)

Primary citation

Appleby, T.C.,Anderson, R.,Fedorova, O.,Pyle, A.M.,Wang, R.,Liu, X.,Brendza, K.M.,Somoza, J.R.
Visualizing ATP-Dependent RNA Translocation by the NS3 Helicase from HCV.
J.Mol.Biol., 405:1139-1153, 2011

PubMed Abstract: The structural mechanism by which nonstructural protein 3 (NS3) from the hepatitis C virus (HCV) translocates along RNA is currently unknown. HCV NS3 is an ATP-dependent motor protein essential for viral replication and a member of the superfamily 2 helicases. Crystallographic analysis using a labeled RNA oligonucleotide allowed us to unambiguously track the positional changes of RNA bound to full-length HCV NS3 during two discrete steps of the ATP hydrolytic cycle. The crystal structures of HCV NS3, NS3 bound to bromine-labeled RNA, and a tertiary complex of NS3 bound to labeled RNA and a non-hydrolyzable ATP analog provide a direct view of how large domain movements resulting from ATP binding and hydrolysis allow the enzyme to translocate along the phosphodiester backbone. While directional translocation of HCV NS3 by a single base pair per ATP hydrolyzed is observed, the 3' end of the RNA does not shift register with respect to a conserved tryptophan residue, supporting a "spring-loading" mechanism that leads to larger steps by the enzyme as it moves along a nucleic acid substrate.

PubMed: 21145896
DOI: 10.1016/j.jmb.2010.11.034

Experimental method

X-RAY DIFFRACTION (2 Å)