Genome-wide siRNA Screening at Biosafety Level 4 Reveals a Crucial Role for Fibrillarin in Henipavirus Infection

PLoS Pathog. 2016 Mar 24;12(3):e1005478. doi: 10.1371/journal.ppat.1005478. eCollection 2016 Mar.

Abstract

Hendra and Nipah viruses (genus Henipavirus, family Paramyxoviridae) are highly pathogenic bat-borne viruses. The need for high biocontainment when studying henipaviruses has hindered the development of therapeutics and knowledge of the viral infection cycle. We have performed a genome-wide siRNA screen at biosafety level 4 that identified 585 human proteins required for henipavirus infection. The host protein with the largest impact was fibrillarin, a nucleolar methyltransferase that was also required by measles, mumps and respiratory syncytial viruses for infection. While not required for cell entry, henipavirus RNA and protein syntheses were greatly impaired in cells lacking fibrillarin, indicating a crucial role in the RNA replication phase of infection. During infection, the Hendra virus matrix protein co-localized with fibrillarin in cell nucleoli, and co-associated as a complex in pulldown studies, while its nuclear import was unaffected in fibrillarin-depleted cells. Mutagenesis studies showed that the methyltransferase activity of fibrillarin was required for henipavirus infection, suggesting that this enzyme could be targeted therapeutically to combat henipavirus infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chlorocebus aethiops
  • Chromosomal Proteins, Non-Histone / genetics
  • Chromosomal Proteins, Non-Histone / metabolism*
  • HeLa Cells
  • Hendra Virus / metabolism
  • Henipavirus Infections / virology*
  • Humans
  • Mutation
  • Nipah Virus / enzymology*
  • Nipah Virus / genetics
  • Nipah Virus / pathogenicity
  • RNA, Small Interfering
  • Vero Cells
  • Viral Matrix Proteins / metabolism

Substances

  • Chromosomal Proteins, Non-Histone
  • RNA, Small Interfering
  • Viral Matrix Proteins
  • fibrillarin

Grant support

This work was supported by The Commonwealth Scientific and Industrial Research Organisation and the Australian National Health and Medical Research Council (grant 1042452 to CRS). The Victorian Centre for Functional Genomics is funded by the Australian Cancer Research Foundation (ACRF), the Victorian Department of Industry, Innovation and Regional Development (DIIRD), the Australian Phenomics Network (APN) and supported by funding from the Australian Government’s Education Investment Fund through the Super Science Initiative, the Australasian Genomics Technologies Association (AMATA), the Brockhoff Foundation and the Peter MacCallum Cancer Centre Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.