Mutagenesis of the 3'42 nucleotide host protein binding element of the MHV 3'UTR.

Abstract

The mouse hepatitis virus (MHV) genome is a 32kb message sense single stranded RNA. Studies with defective interfering RNAs have shown that the 3′ terminal 447nt are required for replication (Kim et al., 1993; Lin et al., 1993). Previous studies have identified two host protein binding elements within the 3’ terminal 166nt of the 3′UTR. The first of these is located at nucleotides 154-129 [assigning position 1 to the first nucleotide 5′ of the poly (A)] tail and the second is located within the 3′ terminal 42 nucleotides (Liu et al, 1997; Yu and Leibowitz, 1995). Both elements contain the conserved motif UGAARNGAAGUU which is required for host protein binding and for DI RNA replication (Yu and Leibowitz, 1995; Liu et al., 1997). In the present study we further identify nucleotides involved in host protein binding and explore the role of RNA secondary structure in this process.