Recombinant HCV NS3 and NS5B enzymes exhibit multiple posttranslational modifications for potential regulation
Posttranslational modification (PTM) of proteins is critical to modulate protein function and to improve the functional diversity of polypeptides. In this report, we have analyzed the PTM of both hepatitis C virus NS3 and NS5B enzyme proteins, upon their individual expression in insect cells under the baculovirus expression system. Using mass spectrometry, we present evidence that these recombinant proteins exhibit diverse covalent modifications on certain amino acid side chains, such as phosphorylation, ubiquitination, and acetylation. Although the functional implications of these PTM must be further addressed, these data may prove useful toward the understanding of the complex regulation of these key viral enzymes and to uncover novel potential targets for antiviral design.
KeywordsHepatitis C virus HCV NS3 NS5B Posttranslational modification Protein regulation
We thank Drs. Stephen Barnes and Landon Wilson from TMPL at UAB for the mass spectrometry analyses. We appreciate continuous support from Dr. Stanley M. Lemon, and Dr. Minkyung Yi. We thank Dr. Takaji Wakita for the transfer of pFGR-JFH1 plasmid utilized in our research. We thank all members of our laboratories for fruitful discussions while this work was carried out. This research has been supported by grants from CONICYT, Basal Project AFB 170004 (A.L.), FONDECYT 1160480 (A.L.), FONDECYT 1100200 (R.A.V.), and PCHA/Doctorado Nacional/2014-21140956 (S.H.).
RAV contributed to the study conception and design. SH and AD performed the experiments. RAV wrote the manuscript. SH, AD, RAV, and AL checked and revised it. RAV and AL contributed with funding. All authors read and approved the final manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
This article does not contain any studies with animals that required ethical approval.
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