Poly(rC) binding proteins mediate poliovirus mRNA stability

K E Murray1, A W Roberts, D J Barton

  • 1Department of Microbiology, University of Colorado Health Sciences Center, Denver 80262, USA.

RNA (New York, N.Y.)
|August 11, 2001
PubMed

Insights

Poliovirus mRNA stability is mediated by poly(rC) binding proteins (PCBPs) interacting with the 5' cloverleaf structure. This interaction protects viral RNA from degradation, crucial for poliovirus replication.

Area of Science:

  • Virology
  • Molecular Biology
  • RNA Biology

Background:

  • Poliovirus RNA features a 5'-terminal cloverleaf structure forming ribonucleoprotein complexes with poly(rC) binding proteins (PCBPs).
  • The functional role of these ribonucleoprotein complexes in poliovirus replication remains to be fully elucidated.

Purpose of the Study:

  • To determine the functional role of PCBP-RNA complexes in poliovirus replication.
  • To investigate the impact of PCBP binding on poliovirus mRNA stability, translation, and RNA synthesis.

Main Methods:

  • Utilized HeLa S10 translation-replication reactions to assay poliovirus mRNA stability, translation, and negative-strand RNA synthesis.
  • Employed ribohomopoly(C) RNA competitor and a C24A mutation to disrupt PCBP binding.
  • Assessed the effect of a 5'-terminal 7-methylguanosine cap on mRNA stability.

Main Results:

  • Ribohomopoly(C) destabilized wild-type poliovirus mRNA, an effect blocked by the 5' cap.
  • PCBP binding, mediated by the 5' cloverleaf structure, is essential for poliovirus mRNA stability.
  • A C24A mutation preventing PCBP binding rendered mRNA unstable, but did not affect translation or negative-strand RNA synthesis.

Conclusions:

  • Poly(rC) binding proteins (PCBPs) mediate poliovirus mRNA stability through interaction with the 5'-terminal cloverleaf structure.
  • This mechanism is likely conserved among picornaviruses, including coxsackieviruses, echoviruses, and rhinoviruses, influencing viral replication.

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