MS2 Coat Protein Mutants Which Bind Qβ RNA

Authors

Marc Spingola, University of New Mexico
David Peabody, University of New Mexico

Document Type

Article

Abstract

The coat proteins of the RNA phages MS2 and Qβ are structurally homologous, yet they specifically bind different RNA structures. In an effort to identify the basis of RNA binding specificity we sought to isolate mutants that convert MS2 coat protein to the RNA binding specificity of Qβ. A library of mutations was created which selectively substitutes amino acids within the RNA binding site. Genetic selection for the ability to repress translation from the Qβ translational operator led to the isolation of several MS2 mutants that acquired binding activity for Qβ RNA. Some of these also had reduced abilities to repress translation from the MS2 translational operator. These changes in RNA binding specificity were the results of substitutions of amino acid residues 87 and 89. Additional codondirected mutagenesis experiments confirmed earlier results showing that the identity of Asn87 is important for specific binding of MS2 RNA. Glu89, on the other hand, is not required for recognition of MS2 RNA, but prevents binding of Qβ RNA.

Publication Date

July 1997

Publication Title

Nucleic Acids Research

Volume

25

Issue

14

First Page

2808

Last Page

2815

DOI

10.1093/nar/25.14.2808

Recommended Citation

Spingola, Marc and Peabody, David, "MS2 Coat Protein Mutants Which Bind Qβ RNA" (1997). Biology Department Faculty Works. 164.
DOI: https://doi.org/10.1093/nar/25.14.2808
Available at: https://irl.umsl.edu/biology-faculty/164