The Interaction between the RNA-Dependent RNA-Polymerase of the Hepatitis Virus and RNA Matrices

Abstract

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Hepatitis C is one of the most dangerous and widespread viral diseases. Currently, the World Health Organization estimates that about 170 million people are infected with the hepatitis C virus (HCV), the causative agent of infection, in almost every country in the world. The RN A-dependent RN A-polymerase (R-RN AP, virus nonstructural protein) is a key fragment that carries out HCV genome replication. R-RN AP is about 65 kDA in molecular weight and localized on the endoplasmic reticulum membrane of infected hepatic cells by the C-tail α-spiral transmembrane domain (21 a.r.). One characteristic feature of R-RN AP is its ability to catalyze RN A synthesis by both primer-dependent and primer-independent (de novo) mechanisms [1]. In the first case, in the in vitro experiments, the primer-matrix poly(rA)-oligo(rU) duplex is used as the RN A matrix; in the second case, the HCV genome fragments are used. It is suggested that oligomer from several identical R-RN AP molecules takes part in the replication. Moreover, oligomer was discovered to be composed of H502 and E18 amino-acid residues located in the interaction area of protein globules [2]. Earlier, we obtained the E.coli strain (the HCV R-RN AP producer) which allows a highly purified recombinant protein with a cell culture yield of up to 6 mg/l to be created and we developed a procedure for enzyme purification to the homogeneous condition (the data of electrophoresis in the polyacrylamide gel) [3]. The purification procedure included methods similar to those described in the corresponding literature [4]; the kinetic parameters of the primer-dependent reaction determined for the polymerase sample were consistent with the literature data as well [5].