Hantaviruses, members of the Bunyaviridae family are enveloped negative stranded emerging RNA viruses and category A pathogens that are transmitted to humans through aerosolized excreta of infected rodents. Hantaviruses have evolved a unique translation mechanism, operated by viral nucleocapsid protein (N), which preferentially facilitates the translation of viral mRNAs in host cells where cellular transcripts are competing for the same translation machinery. This translation mechanism is conceptually different from all translation mechanisms known to date, and facilitates the translation of capped mRNAs without the requirement of eIF4F cap binding complex. Hantaviral mRNAs contain a unique 42-52 nucleotide long 5'untranslated region (UTR) harboring a highly conserved triplet repeat sequence at the 5'terminus that specifically binds to the trimeric N protein. In addition, N also binds to the 40S ribosomal subunit via the ribosomal protein S19 (RPS19), located at the head region of 40S subunit. N preferentially loads 40S ribosomal subunits onto the viral mRNA 5'UTR and facilitates their translation in vitro. We will further characterize the role of 5'UTR in the translation of viral mRNAs by N-mediated translation mechanism in cells. We will determine whether hantaviral mRNAs specifically depend on N-mediated translation mechanism for their translation. We will also identify and characterize the RPS19 binding domain in N protein and demonstrate the role of N-RPS19 interaction in N-mediated translation strategy. We will determine whether N protein remains associated with the 40S subunit of 80S ribosome in polysome associated mRNAs. These studies will shed light on a novel mechanism of translation initiation that likely most negative stranded RNA viruses use to favor the translation of their mRNAs in host cells during infection. The proposed studies will also reveal novel targets for antiviral drug design in future.
There is no treatment for hantavirus associated disease at present. The major goal of this application is to delineate the mechanism of hantavirus replication in cells. In addition, the proposed studies will help in the identification of targets for antiviral drug design.
|Roy, Anuradha; Mir, Mohammad A (2017) Development of High-Throughput Screening Assay for Antihantaviral Therapeutics. SLAS Discov 22:767-774|
|Salim, Nilshad N; Ganaie, Safder S; Roy, Anuradha et al. (2016) Targeting a Novel RNA-Protein Interaction for Therapeutic Intervention of Hantavirus Disease. J Biol Chem 291:24702-24714|
|Wang, Zekun; Mir, Mohammad A (2015) Andes virus nucleocapsid protein interrupts protein kinase R dimerization to counteract host interference in viral protein synthesis. J Virol 89:1628-39|
|Ganaie, Safder S; Haque, Absarul; Cheng, Erdong et al. (2014) Ribosomal protein S19-binding domain provides insights into hantavirus nucleocapsid protein-mediated translation initiation mechanism. Biochem J 464:109-21|
|Cheng, Erdong; Wang, Zekun; Mir, Mohammad A (2014) Interaction between hantavirus nucleocapsid protein (N) and RNA-dependent RNA polymerase (RdRp) mutants reveals the requirement of an N-RdRp interaction for viral RNA synthesis. J Virol 88:8706-12|
|Ganaie, Safder S; Mir, Mohammad A (2014) The role of viral genomic RNA and nucleocapsid protein in the autophagic clearance of hantavirus glycoprotein Gn. Virus Res 187:72-6|