Maturation of the Polymerase Polyprotein of the Coronavirus MHV Strain JHM Involves a Cascade of Proteolytic Processing Events

  • Jennifer J. Schiller
  • Susan C. Baker
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 440)


The RNA polymerase gene of the murine Coronavirus mouse hepatitis virus (MHV) encodes a polyprotein of greater than 750 kDa. The amino-terminal cleavage product of the MHV polymerase polyprotein, p28, has been shown to be cleaved from the polyprotein by the virus-encoded protease PCP-1. We aim to identify the MHV-JHM proteolytic products downstream of p28 and to determine which viral proteinase domains are responsible for generating each of them. To this end, we have generated antisera directed at specific MHV-JHM ORF la regions and have used these antisera to identify six viral proteins, representing a large portion of ORF la, from MHV-JHM-infected cells. These proteins include p28, p72, p65, p250, p210, and p27.


Mouse Hepatitis Virus Murine Coronavirus Cysteine Proteinase Domain Mouse Hepatitis Virus Strain Follow Pulse Label 
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Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • Jennifer J. Schiller
    • 1
  • Susan C. Baker
    • 1
  1. 1.Department of Microbiology and ImmunologyLoyola University of Chicago Stritch School of MedicineMaywoodUSA

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