Mutations in the 2C region of poliovirus responsible for altered sensitivity to benzimidazole derivatives

J Virol. 2000 May;74(9):4146-54. doi: 10.1128/jvi.74.9.4146-4154.2000.

Abstract

MRL-1237, [1-(4-fluorophenyl)-2-(4-imino-1,4-dihydropyridin-1-yl) methylbenzimidazole hydrochloride], is a potent and selective inhibitor of the replication of enteroviruses. To reveal the target molecule of MRL-1237 in viral replication, we selected spontaneous MRL-1237-resistant poliovirus mutants. Of 15 MRL-1237-resistant mutants obtained, 14 were cross-resistant to guanidine hydrochloride (mrgr), while 1 was susceptible (mrgs). Sequence analysis of the 2C region revealed that the 14 mrgr mutants contained a single nucleotide substitution that altered an amino acid residue from Phe-164 to Tyr. The mrgs mutant, on the other hand, contained a substitution of Ile-120 to Val. Through the construction of a cDNA-derived mutant, we confirmed that the single mutation at Phe-164 was really responsible for the reduced susceptibility to MRL-1237. MRL-1237 inhibited poliovirus-specific RNA synthesis in HeLa cells infected with a wild strain but not with an F164Y mutant. We furthermore examined the effect of mutations of the 2C region on the drug sensitivity of cDNA-derived guanidine-resistant and -dependent mutants. Two guanidine-resistant mutants were cross-resistant to MRL-1237 but remained susceptible to another benzimidazole, enviroxime. Either MRL-1237 or guanidine stimulated the viral replication of two guanidine-dependent mutants, but enviroxime did not. These results indicate that MRL-1237, like guanidine, targets the 2C protein of poliovirus for its antiviral effect.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antiviral Agents / chemistry
  • Antiviral Agents / pharmacology*
  • Benzimidazoles / chemistry
  • Benzimidazoles / pharmacology*
  • Carrier Proteins / drug effects
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Drug Resistance, Microbial
  • HeLa Cells
  • Humans
  • Molecular Sequence Data
  • Molecular Structure
  • Mutagenesis, Site-Directed
  • Poliovirus / drug effects*
  • Poliovirus / genetics
  • Pyridines / pharmacology*
  • RNA, Viral / biosynthesis
  • Sequence Homology, Amino Acid
  • Viral Nonstructural Proteins / drug effects
  • Viral Nonstructural Proteins / genetics
  • Viral Nonstructural Proteins / metabolism*

Substances

  • Antiviral Agents
  • Benzimidazoles
  • Carrier Proteins
  • MRL 1237
  • Pyridines
  • RNA, Viral
  • Viral Nonstructural Proteins
  • 2C protein, viral