Identification of a PGXPP degron motif in dishevelled and structural basis for its binding to the E3 ligase KLHL12

DOI: 10.1098/rsob.200041

Authors: Zhuoyao Chen (Structural Genomics Consortium, University of Toronto) , Gregory A. Wasney (Structural Genomics Consortium, University of Toronto) , Sarah Picaud (Structural Genomics Consortium, University of Toronto) , Panagis Filippakopoulos (Nuffield Department of Clinical Medicine, Structural Genomics Consortium, University of Oxford, U.K.) , Masoud Vedadi (Structural Genomics Consortium, University of Toronto) , Vincenzo D'Angiolella (Cancer Research UK and Medical Research Council Institute for Radiation Oncology, University of Oxford) , Alex N. Bullock (Structural Genomics Consortium, University of Oxford)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Open Biology , VOL 10

State: Published (Approved)
Published: June 2020
Diamond Proposal Number(s): 15433

Abstract: Wnt signalling is dependent on dishevelled proteins (DVL1-3), which assemble an intracellular Wnt signalosome at the plasma membrane. The levels of DVL1-3 are regulated by multiple Cullin-RING E3 ligases that mediate their ubiquitination and degradation. The BTB-Kelch protein KLHL12 was the first E3 ubiquitin ligase to be identified for DVL1-3, but the molecular mechanisms determining its substrate interactions have remained unknown. Here, we mapped the interaction of DVL1-3 to a ‘PGXPP' motif that is conserved in other known partners and substrates of KLHL12, including PLEKHA4, PEF1, SEC31 and DRD4. To determine the binding mechanism, we solved a 2.4 Å crystal structure of the Kelch domain of KLHL12 in complex with a DVL1 peptide that bound with low micromolar affinity. The DVL1 substrate adopted a U-shaped turn conformation that enabled hydrophobic interactions with all six blades of the Kelch domain β-propeller. In cells, the mutation or deletion of this motif reduced the binding and ubiquitination of DVL1 and increased its stability confirming this sequence as a degron motif for KLHL12 recruitment. These results define the molecular mechanisms determining DVL regulation by KLHL12 and establish the KLHL12 Kelch domain as a new protein interaction module for a novel proline-rich motif.

Journal Keywords: ubiquitin; Cul3; BTB domain; degradation; Kelch; E3 ligase

Subject Areas: Biology and Bio-materials


Instruments: I02-Macromolecular Crystallography , I04-Macromolecular Crystallography , I24-Microfocus Macromolecular Crystallography

Added On: 26/08/2020 10:05

Documents:
rsob.200041.pdf

Discipline Tags:

Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)