Picornaviral processing: some new ideas.

A C Palmenberg

doi:10.1002/jcb.240330306

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Picornaviral processing: some new ideas.

A C Palmenberg

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Abstract

Mature picornaviral proteins are derived by progressive, post-translational cleavage of a giant precursor polyprotein. At least three viral-encoded proteolytic activities are involved in the processing. The first cleavage takes place while the polyprotein is still nascent on a ribosome. In poliovirus, this event is probably catalyzed by peptide 2A, a protein from the middle portion of the genome. Most subsequent processing is effected by viral protease 3C, a thiol-type enzyme, responsible for eight to ten self-cleaving and autocatalytic reactions within the polyprotein. The final proteolytic processing event, maturation of the VPO peptide, may occur by a novel, autocatalytic, serine-type mechanism, where viral RNA serves as proton-acceptor during the cleavage reaction.

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Amino Acid Sequence Peptide Hydrolases Picornaviridae Protein Conformation Protein Processing, Post-Translational Viral Proteins Viral Structural Proteins Journal Article Research Support, U.S. Gov't, P.H.S.Review

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A C Palmenberg. 1987. Picornaviral processing: some new ideas.. https://doi.org/10.1002/jcb.240330306

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