Misfolded plant virus proteins: elicitors and targets of ubiquitylation

Jockusch H, Wiegand C. Misfolded plant virus proteins: elicitors and targets of ubiquitylation. FEBS LETTERS. 2003;545(2-3):229-232.Mutant tobacco mosaic virus (TMV) coat proteins (CPs) with known amino acid replacements provide well defined examples of destabilized tertiary structures. Here we show that misfolded TMV CPs, but not functional wild-type CPs, induce massive ubiquitylation in tobacco cells and that denatured, insoluble CP subunits are the main substrates of ubiquitin conjugation. As TMV CPs can be easily manipulated they are unique tools to study the molecular basis of the plant cell's response to aberrant protein structures and the associated intracellular stress reactions. (C) 2003 Published by Elsevier Science B.V. on behalf of the Federation of European Biochemical Societies