The N-Terminal α-Helix of Potato Virus X-Encoded RNA-Dependent RNA Polymerase Is Required for Membrane Association and Multimerization

Viruses. 2022 Aug 28;14(9):1907. doi: 10.3390/v14091907.

Abstract

Positive-sense single-stranded RNA viruses replicate in virus-induced membranous organelles for maximum efficiency and immune escaping. The replication of potato virus X (PVX) takes place on the endoplasmic reticulum (ER); however, how PVX-encoded RNA-dependent RNA polymerase (RdRp) is associated with the ER is still unknown. A proline-kinked amphipathic α-helix was recently found in the MET domain of RdRp. In this study, we further illustrate that the first α-helix of the MET domain is also required for ER association. Moreover, we found that the MET domain forms multimers on ER and the first α-helix is essential for multimerization. These results suggest that the RdRp of PVX adopts more than one hydrophobic motif for membrane association and for multimerization.

Keywords: RNA-dependent RNA polymerase; membrane association; methyltransferase; multimerization; potato virus X.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Endoplasmic Reticulum
  • Potexvirus* / genetics
  • Proline
  • Protein Conformation, alpha-Helical
  • RNA, Viral / genetics
  • RNA-Dependent RNA Polymerase / genetics
  • Virus Replication

Substances

  • RNA, Viral
  • Proline
  • RNA-Dependent RNA Polymerase

Grants and funding

This research was funded by the National Natural Foundation of China, grant number 32022071.