Mutations in a CCHC zinc-binding motif of the reovirus sigma 3 protein decrease its intracellular stability.

T Mabrouk; G Lemay

doi:10.1128/jvi.68.8.5287-5290.1994

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Mutations in a CCHC zinc-binding motif of the reovirus sigma 3 protein decrease its intracellular stability.

T Mabrouk·G Lemay

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Abstract

It has been demonstrated that the sigma 3 protein of reovirus harbors a zinc-binding domain in its amino-terminal portion. A putative zinc finger in the CCHH form is located in this domain and was considered to be a good candidate for the zinc-binding motif. We performed site-directed mutagenesis to substitute amino acids in this region and demonstrated that many of these mutants, although expressed in COS cells, were unstable compared with the wild-type protein. Further analysis revealed that zinc-binding capability, as measured by retention on a zinc chelate affinity adsorbent, correlates with stability. These studies also allowed us to identify a CCHC box as the most probable zinc-binding motif.

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Amino Acid Sequence Animals Capsid Proteins Cell Line Molecular Sequence Data Mutagenesis, Site-Directed Protein Binding RNA-Binding Proteins Reoviridae Sequence Homology, Amino Acid Viral Proteins Zinc Journal Article Research Support, Non-U.S. Gov't

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T Mabrouk, G Lemay. 1994. Mutations in a CCHC zinc-binding motif of the reovirus sigma 3 protein decrease its intracellular stability.. https://doi.org/10.1128/jvi.68.8.5287-5290.1994

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