Intrinsic disorder mediates hepatitis C virus core-host cell protein interactions

Patrick T. Dolan, Andrew P. Roth, Bin Xue, Ren Sun, A. Keith Dunker, Vladimir N. Uversky, Douglas J. Lacount

Research output: Contribution to journalArticle

26 Scopus citations

Abstract

Viral proteins bind to numerous cellular and viral proteins throughout the infection cycle. However, the mechanisms by which viral proteins interact with such large numbers of factors remain unknown. Cellular proteins that interact with multiple, distinct partners often do so through short sequences known as molecular recognition features (MoRFs) embedded within intrinsically disordered regions (IDRs). In this study, we report the first evidence that MoRFs in viral proteins play a similar role in targeting the host cell. Using a combination of evolutionary modeling, protein-protein interaction analyses and forward genetic screening, we systematically investigated two computationally predicted MoRFs within the N-terminal IDR of the hepatitis C virus (HCV) Core protein. Sequence analysis of the MoRFs showed their conservation across all HCV genotypes and the canine and equine Hepaciviruses. Phylogenetic modeling indicated that the Core MoRFs are under stronger purifying selection than the surrounding sequence, suggesting that these modules have a biological function. Using the yeast two-hybrid assay, we identified three cellular binding partners for each HCV Core MoRF, including two previously characterized cellular targets of HCV Core (DDX3X and NPM1). Random and site-directed mutagenesis demonstrated that the predicted MoRF regions were required for binding to the cellular proteins, but that different residues within each MoRF were critical for binding to different partners. This study demonstrated that viruses may use intrinsic disorder to target multiple cellular proteins with the same amino acid sequence and provides a framework for characterizing the binding partners of other disordered regions in viral and cellular proteomes.

Original languageEnglish (US)
Pages (from-to)221-235
Number of pages15
JournalProtein Science
Volume24
Issue number2
DOIs
StatePublished - Feb 1 2015

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Keywords

  • hepatitis C virus
  • hepatitis virus
  • host-pathogen interactions
  • intrinsically disordered proteins
  • protein-protein interactions
  • systems biology
  • viral protein
  • virus

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology

Cite this

Dolan, P. T., Roth, A. P., Xue, B., Sun, R., Dunker, A. K., Uversky, V. N., & Lacount, D. J. (2015). Intrinsic disorder mediates hepatitis C virus core-host cell protein interactions. Protein Science, 24(2), 221-235. https://doi.org/10.1002/pro.2608