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Team:Warwick/Safety
From 2014.igem.org
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RNA dependent RNA polymerase (RdRp) RdRp is an enzyme which catalyzes the replication of RNA from an RNA template, an essential protein for all viruses with an RNA genome. RdRp in Hepatitis C virus is also referred to as the NS5B protein, with a total molecular weight of 65 kDa. Heterelogous expression of NS5B has been achieved in insect and bacterial hosts, performing RNA-dependent RNA synthesis (Behrens et al., 1996; Lohmann et al., 1997). Hydrophobic C-terminal 21 amino acid residues cause insertion into the membrane, essential for HCV RNA replication (Moradpour et al., 2004). Amino acid substitution experiments of the 21 amino acid insertion sequence indicate functions beyond a membrane anchor role, with intracellular protein-protein interactions implicated (Moradpour et al., 2004).C-terminal tail preceding the C-terminal hydrophobic insertion sequence interacts with structural elements including the β-hairpin loop of NS5b (Leveque et al., 2003). The β-hairpin loop is believed to position the 3' terminus of the HCV viral RNA for correct initiation of viral RNA synthesis (Hong et al., 2001). RdRp initiates viral RNA synthesis with nucleotidyl transfer activity found within palm motifs A and C, with several amino acid residues implicated in NTP triphosphate contact (Bressanelli et al., 2002). NS5B activity has been demonstrated in vitro, with synthesis of full length HCV RNA (Lohmann et al., 1997; Ferrari et al., 1999). The 5’ and 3’ untranslated regions (UTRs) of the HCV genome contain ordered RNA structures, which are evolutionary conserved and contain crucial cis-acting elements for viral RNA replication. 150 nt in the 3’ termini of HCV RNA contains elements which are essential for RdRp binding and replication of viral RNA (Cheng et al., 1999; Yi and Lemon, 2003). http://www.ncbi.nlm.nih.gov/books/NBK1629/#ch10.r51 i | ||
