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The rubella virus nonstructural protease recognizes itself via an internal sequence present upstream of the cleavage site for trans-activity.

H H Chen·C J Stark·C D Atreya
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Abstract

The substrate requirement for rubella virus protease trans-activity is unknown. Here, we analyzed the cleavability of RV P200-derived substrates varying in their N-terminal lengths (72-475 amino acids) from the cleavage site by the RV protease trans-activity. Only substrates with at least 309 amino acid residues N-terminal to the cleavage site were able to undergo cleavage. Further, rubella sequence was found to be necessary in the N-terminal region of the substrate, whereas a heterologous sequence C-terminal to the cleavage site was tolerated. These results demonstrated a requirement for residues located between amino acids 994-1102 of the RV P200 polyprotein, besides its cleavage site for RV protease trans-activity. This region overlaps with the starting site of the essential cis-protease activity of RV P200 polyprotein. This is a novel observation for a viral protease of the family Togaviridae.

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Binding SitesPeptide HydrolasesPolyproteinsProtein Processing, Post-TranslationalProtein Structure, TertiaryRubella virusSequence DeletionSubstrate SpecificityViral Nonstructural ProteinsJournal ArticleResearch Support, Non-U.S. Gov't

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H H Chen, C J Stark, C D Atreya. 2006-03-27. The rubella virus nonstructural protease recognizes itself via an internal sequence present upstream of the cleavage site for trans-activity.. https://doi.org/10.1007/s00705-006-0744-9

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