Enterovirus RNA Translation and Replication
Principal Investigator: David J Barton
Abstract: DESCRIPTION (provided by applicant): Poliovirus and related human enteroviruses cause a diverse spectrum of human diseases including acute flaccid paralysis (paralytic poliomyelitis), aseptic meningitis, myocarditis, conjunctivitis and fatal systemic infections of neonates. Poliovirus (PV), the prototypic human enterovirus, is well characterized at the molecular level and serves as a model organism for detailed studies of human enterovirus mRNA translation, RNA replication, and virus assembly. In this proposal we will exploit a remarkable cell-free replication system and tissue culture systems to investigate the mechanisms of PV mRNA stability, PV mRNA translation, and PV RNA replication. In the previous funding period we made three important discoveries: 1) we discovered mechanisms by which naturally uncapped PV mRNA assembles polysomes uncoupled from host cell mRNA turnover machinery, 2) we discovered an evolutionarily ancient telomerase-like mechanism of RNA replication that maintains the integrity of the poly(A) tail at the 3'end of viral RNA genomes, and 3) we discovered an RNA structure in PV and related group C enteroviruses that functions as a competitive inhibitor of ribonuclease L, an antiviral endoribonuclease. Experiments will be performed to: 1) determine how PV and related human enteroviruses uncouple viral mRNA translation from host cell mRNA turnover pathways, and 2) elucidate molecular features associated with the telomerase-like mechanisms of PV RNA replication. These investigations will reveal how the seemingly arcane mechanisms of viral mRNA translation and viral RNA replication represent concerted strategies shaped by the selective pressures of host mRNA turnover machinery. The telomerase-like mechanisms of PV RNA replication, if substantiated by the proposed investigation, will have significant impact on our understanding of molecular evolution, drawing attention to the common features and mechanisms of a viral RNA-dependent RNA polymerase and eukaryotic telomerase reverse-transcriptase. Insights supported by the proposed investigation will be important for designing safe and effective vaccines and novel antiviral drugs for PV and other picornaviruses. PUBLIC HEALTH RELEVANCE: Our investigations provide information applicable to many common human pathogens. The molecular processes under investigation in this project are shared among many picornaviruses, including hundreds of human enteroviruses and human rhinoviruses, which together afflict at one or more times every human being in the US and around the world. Our experiments are designed to determine how specific host proteins detect and destroy human enterovirus and rhinovirus mRNAs and how these viruses evade and counteract such host enzymes to maintain the integrity of their RNA genomes. This information can be used to improve poliovirus vaccines, to create new vaccines against related human picornaviruses, and to optimize antiviral drugs designed to activate specific host enzymes that destroy viral RNA. The success of the poliovirus eradication campaign may depend upon improved poliovirus vaccines and new antiviral drugs.
Funding Period: ----------------1998 - ---------------2015-
more information: NIH RePORT
- Ribonuclease L and metal-ion-independent endoribonuclease cleavage sites in host and viral RNAsDaphne A Cooper
Department of Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA, Department of Cancer Biology, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH 44195, USA, Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA and Program in Molecular Biology, University of Colorado School of Medicine, Aurora, CO 80045, USA
Nucleic Acids Res 42:5202-16. 2014..Monitoring the frequency and location of metal-ion-independent endoribonuclease cleavage sites within host and viral RNAs reveals, in part, how these enzymes contribute to health and disease. ..
- Cis-active RNA elements (CREs) and picornavirus RNA replicationBenjamin P Steil
Department of Microbiology and Program in Molecular Biology, University of Colorado Denver, School of Medicine, United States
Virus Res 139:240-52. 2009..We review the growing body of knowledge regarding picornavirus CREs and discuss how CRE RNAs work coordinately with viral replication proteins and other cis-active RNAs in the 5' and 3' NTRs during RNA replication...
- Poliovirus polymerase residue 5 plays a critical role in elongation complex stabilitySarah E Hobdey
Department of Biochemistry and Molecular Biology, 1870 Campus Delivery, Colorado State University, Fort Collins, Colorado 80523 1870, USA
J Virol 84:8072-84. 2010....
- A template RNA entry channel in the fingers domain of the poliovirus polymeraseMatthew G Kortus
Department of Biochemistry and Molecular Biology, Colorado State University, 1870 Campus Delivery, Colorado State University, Fort Collins, CO 80523 1870, USA
J Mol Biol 417:263-78. 2012..These data identify key residues within the template RNA entry channel and begin to define their distinct mechanistic roles within RNA ECs...