The role of the host Ca/Mn pump in emergence of novel viral RNA recombinants

Summary

Principal Investigator: Peter Nagy
Abstract: DESCRIPTION (provided by applicant): Emergence of new viruses is a continuing threat to our society. Evolution of plus- stranded RNA viruses is frequently driven by RNA recombination, a process that joins noncontiguous RNA segments together, creating novel combinations of genes or regulatory RNA sequences. Recombination is important for RNA viruses to overcome immunity, jump species and change viral pathogenicity in all types of living organisms. Studies on viral RNA recombination are critical to understand the recombination process and the role of specific host genes, whose roles in the recombination process are currently unknown. The investigator will use Tomato bushy stunt virus (TBSV), which is currently the most advanced among viral systems to progress rapidly in understanding the mechanism of RNA recombination and the role of the host genes. The investigator's research opens up a completely new area with the powerful TBSV-yeast model system, which has led to genome-wide screens identifying host genes suppressing RNA recombination for the first time. Additional advantage of the similarity of TBSV replicase proteins to proteins of important pathogens, such as Hepatitis C virus (HCV), dengue virus, West Nile virus and other Flaviviruses and Pestiviruses. Collectively, the major advances with TBSV allow the investigator to conduct experiments on the roles of host factors that are currently only feasible with TBSV, but will open new approaches for studying RNA recombination/evolution for important human pathogens. This proposal focuses on one of the key host factors suppressing RNA recombination. The experiments will dissect the role of Pmr1p Ca2+/Mn2+ pump in viral RNA recombination. Pmr1p is a ubiquitous and conserved protein in eukaryotes. The human homologs of Pmr1p have been shown to play critical roles in genetic diseases, such as Hailey- Hailey Disease and Darier disease. In the absence of Pmr1p, the rate of TBSV RNA recombination is extremely high demonstrating the critical role of the host in viral RNA recombination. In order to characterize the role of Pmr1p in RNA recombination, the investigator will use the advanced genetics tools available for yeast in combination with biochemical approaches. The results obtained in cell-free systems and in yeast model host, will also be confirmed in a native plant host. In addition, in vitro experiments will be conducted with the RdRp of HCV, an important human pathogen, to expand our knowledge on the possible role of Ca2+/Mn2+ pumps in HCV RNA recombination. The following are major strengths of the proposal: (i) Viral RNA recombination is clearly of immense importance for viruses to overcome immunity, jump species and change pathogenicity in all types of living organisms. (ii) The combination of yeast and in vitro systems developed by the investigator is currently the only one in the world suitable for studying the mechanism of host factors involvement in viral RNA recombination. (iii) This research is expected to lead to groundbreaking new discoveries in viral RNA recombination. The highly tractable in vitro and in vivo TBSV system developed by the investigator could prove highly beneficial to studies of other, less amenable RNA viruses. The research holds promise of benefiting society by leading to groundbreaking results in the area of virus recombination/evolution, host-virus interaction and the emergence of new viruses. PUBLIC HEALTH RELEVANCE: Emergence of new viruses is a continuing threat to our society. New plus-stranded RNA viruses emerge frequently due to RNA recombination. Recombination is important for RNA viruses to overcome immunity, jump to new host species or change the severity of symptoms in all types of living organisms. The roles of the host in virus recombination are currently poorly understood due to the lack of tractable virus-host systems. The investigator will use Tomato bushy stunt virus (TBSV), which is currently the most advanced among viral systems to study RNA recombination and the role of the host genes. This proposal focuses on one of the key host factors suppressing RNA recombination by dissecting the role of a Ca2+/Mn2+ pump in viral RNA recombination. The research holds promise of benefiting society by leading to groundbreaking results in the area of virus recombination/evolution, host-virus interaction and the emergence of new viruses.
Funding Period: ----------------2009 - ---------------2011-
more information: NIH RePORT

Top Publications

  1. pmc Proteome-wide overexpression of host proteins for identification of factors affecting tombusvirus RNA replication: an inhibitory role of protein kinase C
    Muhammad Shah Nawaz-Ul-Rehman
    Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, USA
    J Virol 86:9384-95. 2012
  2. ncbi Similar roles for yeast Dbp2 and Arabidopsis RH20 DEAD-box RNA helicases to Ded1 helicase in tombusvirus plus-strand synthesis
    Nikolay Kovalev
    Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, United States
    Virology 432:470-84. 2012
  3. pmc p33-Independent activation of a truncated p92 RNA-dependent RNA polymerase of Tomato bushy stunt virus in yeast cell-free extract
    Judit Pogany
    Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, USA
    J Virol 86:12025-38. 2012
  4. pmc Authentic in vitro replication of two tombusviruses in isolated mitochondrial and endoplasmic reticulum membranes
    Kai Xu
    Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, USA
    J Virol 86:12779-94. 2012
  5. ncbi Yeast screens for host factors in positive-strand RNA virus replication based on a library of temperature-sensitive mutants
    Muhammad Shah Nawaz-ul-Rehman
    Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA
    Methods 59:207-16. 2013
  6. ncbi Characterization of dominant-negative and temperature-sensitive mutants of tombusvirus replication proteins affecting replicase assembly
    Kunj B Pathak
    Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA
    Virology 437:48-61. 2013
  7. pmc Ubiquitination of tombusvirus p33 replication protein plays a role in virus replication and binding to the host Vps23p ESCRT protein
    Daniel Barajas
    Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA
    Virology 397:358-68. 2010
  8. ncbi An inhibitory function of WW domain-containing host proteins in RNA virus replication
    Jun Qin
    College of Life Science, Northwest A and F University, Yangling, Shaanxi, 712100, People s Republic of China
    Virology 426:106-19. 2012

Detail Information

Publications8

  1. pmc Proteome-wide overexpression of host proteins for identification of factors affecting tombusvirus RNA replication: an inhibitory role of protein kinase C
    Muhammad Shah Nawaz-Ul-Rehman
    Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, USA
    J Virol 86:9384-95. 2012
    ....
  2. ncbi Similar roles for yeast Dbp2 and Arabidopsis RH20 DEAD-box RNA helicases to Ded1 helicase in tombusvirus plus-strand synthesis
    Nikolay Kovalev
    Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, United States
    Virology 432:470-84. 2012
    ..We also show that the orthologous AtRH20 DEAD-box helicase from Arabidopsis can increase tombusvirus replication in vitro and in yeast...
  3. pmc p33-Independent activation of a truncated p92 RNA-dependent RNA polymerase of Tomato bushy stunt virus in yeast cell-free extract
    Judit Pogany
    Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, USA
    J Virol 86:12025-38. 2012
    ....
  4. pmc Authentic in vitro replication of two tombusviruses in isolated mitochondrial and endoplasmic reticulum membranes
    Kai Xu
    Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, USA
    J Virol 86:12779-94. 2012
    ....
  5. ncbi Yeast screens for host factors in positive-strand RNA virus replication based on a library of temperature-sensitive mutants
    Muhammad Shah Nawaz-ul-Rehman
    Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA
    Methods 59:207-16. 2013
    ..Overall, we show the power of ts mutant library in identification of host factors for RNA virus replication...
  6. ncbi Characterization of dominant-negative and temperature-sensitive mutants of tombusvirus replication proteins affecting replicase assembly
    Kunj B Pathak
    Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA
    Virology 437:48-61. 2013
    ..Overall, the presented data provide direct evidence that the p33:p33/p92 interaction domains in p33 and p92 are needed for the early stage of virus replication and also influence viral recombination...
  7. pmc Ubiquitination of tombusvirus p33 replication protein plays a role in virus replication and binding to the host Vps23p ESCRT protein
    Daniel Barajas
    Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA
    Virology 397:358-68. 2010
    ..These findings argue that optimal level of p33 ubiquitination plays a regulatory role during tombusvirus infections...
  8. ncbi An inhibitory function of WW domain-containing host proteins in RNA virus replication
    Jun Qin
    College of Life Science, Northwest A and F University, Yangling, Shaanxi, 712100, People s Republic of China
    Virology 426:106-19. 2012
    ..Thus, artificial antiviral proteins with WW domains could be useful antiviral strategy...