Substrate complexes of hepatitis C virus RNA polymerase (HC-J4): structural evidence for nucleotide import and de-novo initiation.
O'Farrell, D., Trowbridge, R., Rowlands, D., Jager, J.(2003) J Mol Biol 326: 1025-1035
- PubMed: 12589751 
- DOI: https://doi.org/10.1016/s0022-2836(02)01439-0
- Primary Citation of Related Structures:  
1NB4, 1NB6, 1NB7 - PubMed Abstract: 
Several crystal structures of the hepatitis C virus NS5B protein (genotype-1b, strain J4) complexed with metal ions, single-stranded RNA or nucleoside-triphosphates have been determined. These complexes illustrate how conserved amino acid side-chains, together with essential structural features within the active site, control nucleotide binding and likely mediate de-novo initiation. The incoming nucleotide interacts with several basic residues from an extension on the NS5B fingers domain, a beta-hairpin from the NS5B thumb domain and the C-terminal arm. The modular, bi-partite fingers domain carries a long binding groove which guides the template towards the catalytic site. The apo-polymerase structure provides unprecedented insights into potential non-nucleoside inhibitor binding sites located between palm and thumb near motif E, which is unique to RNA polymerases and reverse transcriptases.
Organizational Affiliation: 
Astbury Centre of Structural Molecular Biology, School of Biochemistry and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.