Proteome-wide analysis of phospho-regulated PDZ domain interactions

Author(s)
G. N. Sundell, R. Arnold, M. Ali, P. Naksukpaiboon, J. Orts, P. Guntert, C. N. Chi, Y. Ivarsson
Abstract

A key function of reversible protein phosphorylation is to regulate protein–protein interactions, many of which involve short linear motifs (3–12 amino acids). Motif-based interactions are difficult to capture because of their often low-to-moderate affinities. Here, we describe phosphomimetic proteomic peptide-phage display, a powerful method for simultaneously finding motif-based interaction and pinpointing phosphorylation switches. We computationally designed an oligonucleotide library encoding human C-terminal peptides containing known or predicted Ser/Thr phosphosites and phosphomimetic variants thereof. We incorporated these oligonucleotides into a phage library and screened the PDZ (PSD-95/Dlg/ZO-1) domains of Scribble and DLG1 for interactions potentially enabled or disabled by ligand phosphorylation. We identified known and novel binders and characterized selected interactions through microscale thermophoresis, isothermal titration calorimetry, and NMR. We uncover site-specific phospho-regulation of PDZ domain interactions, provide a structural framework for how PDZ domains accomplish phosphopeptide binding, and discuss ligand phosphorylation as a switching mechanism of PDZ domain interactions. The approach is readily scalable and can be used to explore the potential phospho-regulation of motif-based interactions on a large scale.

Organisation(s)
External organisation(s)
Uppsala University, University of Birmingham, Eidgenössische Technische Hochschule Zürich
Journal
Molecular Systems Biology
Volume
14
No. of pages
22
ISSN
1744-4292
DOI
https://doi.org/10.15252/msb.20178129
Publication date
08-2018
Peer reviewed
Yes
Austrian Fields of Science 2012
106006 Biophysics, 106002 Biochemistry
Keywords
ASJC Scopus subject areas
General Agricultural and Biological Sciences, Applied Mathematics, General Biochemistry,Genetics and Molecular Biology, General Immunology and Microbiology
Portal url
https://ucrisportal.univie.ac.at/en/publications/9f55ffc6-8b0e-474a-a51b-ca6a53dea7ff