The noncapsid protein expressed from ORF-206 of turnip yellow mosaic virus (TYMV) is autocatalytically processed by a papain-like protease, producing N-terminal 150-kDa and C-terminal 70-kDa proteins. By introducing two methionine residues near the N-terminus of the 70-kDa protein, we have obtained N-terminal amino acid sequence of that protein produced from [35S]methionine-labeled in vitro translations. The introduction of methionine residues was demonstrated to not interfere with viral replication or proteolysis, as assayed by inoculating mutant RNA transcripts onto whole plants and protoplasts, as well as by translating the RNAs in a rabbit reticulocyte lysate. This has allowed us to determine that the TYMV protease cleaves between alanine1259 and threonine1260 of the precursor protein p206, yielding proteins of calculated Mr 140,618 and 66,037, which will be referred to henceforth as p141 and p66, respectively. The sequence context around the cleavage site is LNGA/TP.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.