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. 1994 Sep 11;22(18):3748–3752. doi: 10.1093/nar/22.18.3748

Mutations that increase the affinity of a translational repressor for RNA.

F Lim 1, D S Peabody 1
PMCID: PMC308357  PMID: 7937087

Abstract

The coat protein of the RNA bacteriophage MS2 is a specific RNA binding protein that represses translation of the viral replicase gene during the infection cycle. As an approach to characterizing the RNA-binding site of coat protein we have isolated a series of coat mutants that suppress the effects of a mutation in the translational operator. Each of the mutants exhibits a super-repressor phenotype, more tightly repressing both the mutant and wild-type operators than does the wild-type protein. The variant coat proteins were purified and subjected to filter binding assays to determine their affinities for the mutant and wild-type operators. Each protein binds the operators from 3 to 7.5-fold more tightly than normal coat protein. The amino acid substitutions seem to extend the normal binding site by introducing new interactions with RNA.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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