In vivo determination of substrate specificity of hepatitis C virus NS3 protease: genetic assay for site-specific proteolysis
| Autor: | Ohkmae K. Park, Sung Yun Kim, Sung Hoon Back, Sung Key Jang, Kye Won Park, Woo Jin Park, Jae Hwan Goo, Yong Jae Lee |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Proteases
Saccharomyces cerevisiae Proteins Receptors Peptide medicine.medical_treatment Recombinant Fusion Proteins Biophysics Saccharomyces cerevisiae Biology Viral Nonstructural Proteins Biochemistry Substrate Specificity Fungal Proteins Scissile bond Genes Reporter Consensus sequence medicine Amino Acids Molecular Biology Integral membrane protein Chromatography High Pressure Liquid Gene Library NS3 Protease Cell Biology Molecular biology Fusion protein Protein Structure Tertiary NS2-3 protease DNA-Binding Proteins Receptors Mating Factor Peptides Transcription Factors |
| Zdroj: | Analytical biochemistry. 284(1) |
| ISSN: | 0003-2697 |
| Popis: | Hepatitis C virus (HCV) NS3 protease is responsible for the processing of the viral polyprotein and is considered as a primary target for the development of anti-HCV therapy. We have developed a genetic method in yeast to screen for good substrate sequences of the NS3 protease. A library of fusion proteins was constructed with a transcription factor, GAL4, linked to the intracellular domain of an integral membrane protein, STE2, by a randomized protease substrate sequence. In yeast cells expressing NS3 protease, the substrate sequences in the fusion proteins were specifically recognized and cleaved. This cleavage resulted in the release of GAL4 from the cytoplasmic membrane and the subsequent activation of reporter genes by GAL4, which was detected by the growth of yeast cells on selective media. Based on the analysis of 69 isolated substrate sequences, a consensus sequence was deduced: (Glu/Asp)-X-Val-Val-(Leu/Pro)-Cys / (Ser/Ala), with the scissile bond being located between Cys and Ser or Ala and X not being determined. This is largely consistent with the previous results obtained by biochemical methods. An oligopeptide containing the deduced sequence was highly efficiently cleaved in vitro by the purified NS3 protease. These data demonstrated that the present genetic method could be used as an efficient tool for the in vivo determination of substrate specificity of proteases. |
| Databáze: | OpenAIRE |
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