title: Ubiquitin Lys 63 chains - second-most abundant, but poorly understood in plants.
abstract: Covalent attachment of the small modifier ubiquitin to Lys ε-amino groups of proteins is surprisingly diverse. Once attached to a substrate, ubiquitin is itself frequently modified by ubiquitin, to form chains. All seven Lys residues of ubiquitin, as well as its N-terminal Met, can be ubiquitylated, implying cellular occurrence of different ubiquitin chain types. The available data suggest that the synthesis, recognition, and hydrolysis of different chain types are precisely regulated. This remarkable extent of control underlies a versatile cellular response to substrate ubiquitylation. In this review, we focus on roles of Lys63-linked ubiquitin chains in plants. Despite limited available knowledge, several recent findings illustrate the importance of these chains as signaling components in plants.
authors.affiliation: Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, Center for Molecular Biology, University of Vienna Vienna, Austria.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Tomanov
authors.affiliation: Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences Vienna, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Luschnig
authors.affiliation: Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, Center for Molecular Biology, University of Vienna Vienna, Austria.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bachmair
keywords: DNA repair; auxin transport; cell signaling; endoctosis; iron response; plant defense; ubiquitin Lys63 chains; vacuolar sorting