Molecular Cell
Volume 58, Issue 1, 2 April 2015, Pages 83-94
Journal home page for Molecular Cell

Article
K29-Selective Ubiquitin Binding Domain Reveals Structural Basis of Specificity and Heterotypic Nature of K29 Polyubiquitin

https://doi.org/10.1016/j.molcel.2015.01.041Get rights and content
Under a Creative Commons license
open access

Highlights

  • Large-scale enzymatic assembly and purification of K29-linked polyubiquitin chains

  • K29 diubiquitin adopts extended conformation in crystal structure

  • Crystal structure of K29 diubiquitin in complex with selective binding domain

  • Presence of K29 chains within mixed/branched chains containing other linkages

Summary

Polyubiquitin chains regulate diverse cellular processes through the ability of ubiquitin to form chains of eight different linkage types. Although detected in yeast and mammals, little is known about K29-linked polyubiquitin. Here we report the generation of K29 chains in vitro using a ubiquitin chain-editing complex consisting of the HECT E3 ligase UBE3C and the deubiquitinase vOTU. We determined the crystal structure of K29-linked diubiquitin, which adopts an extended conformation with the hydrophobic patches on both ubiquitin moieties exposed and available for binding. Indeed, the crystal structure of the NZF1 domain of TRABID in complex with K29 chains reveals a binding mode that involves the hydrophobic patch on only one of the ubiquitin moieties and exploits the flexibility of K29 chains to achieve linkage selective binding. Further, we establish methods to study K29-linked polyubiquitin and find that K29 linkages exist in cells within mixed or branched chains containing other linkages.

Cited by (0)

This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

2

Present address: AB Sciex UK Limited, Warrington, Cheshire WA1 1RX, UK