Proximity-labeling proteomics reveals remodeled interactomes and altered localization of pathogenic SHP2 variants.

Overview

Missense mutations in PTPN11, which encodes the protein tyrosine phosphatase SHP2, are common in several developmental disorders and cancers. While many mutations disrupt auto-inhibition and hyperactivate SHP2, several do not enhance catalytic activity. Both activating and non-activating mutations could potentially drive pathogenic signaling by altering SHP2 interactions or localization. We employed proximity-labeling proteomics to map the interaction networks of wild-type SHP2, ten clinically relevant mutants, and SHP2 bound to an inhibitor that stabilizes its auto-inhibited state. Our analyses reveal mutation- and inhibitor-dependent alterations in the SHP2 interactome, with several mutations also changing localization. Some mutants show increased mitochondrial localization and impact mitochondrial function. This study provides a resource for exploring SHP2 signaling and offers new insights into the molecular basis of SHP2-driven diseases. Furthermore, this work highlights the capacity for proximity-labeling proteomics to detect missense-mutation-dependent changes in protein interactions and localization.