Misfolded plant virus proteins: elicitors and targets of ubiquitylation.
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.
Jockusch
Harald
H
Developmental Biology and Molecular Pathology, Bielefeld University, W7, 33501, Bielefeld, Germany. h.jockusch@uni-bielefeld.de
Wiegand
Christiane
C
D019943:Amino Acid Substitution; D036022:Capsid Proteins / Q000378:metabolism* / Q000502:physiology; D008958:Models, Molecular; D009154:Mutation; D010947:Plants, Toxic; D011487:Protein Conformation; D011489:Protein Denaturation; D013696:Temperature; D014027:Tobacco Mosaic Virus / Q000235:genetics* / Q000254:growth & development; D025801:Ubiquitin / Q000378:metabolism*
D036022:Capsid Proteins; D025801:Ubiquitin