Proteolysis of transmembrane receptors is a critical cellular communication mechanism dysregulated in disease, yet decoding proteolytic regulation mechanisms of hundreds of shed receptors is hindered by difficulties controlling stimuli and unknown fates of cleavage products. Notch proteolytic regulation is a notable exception, where intercellular forces drive exposure of a cryptic protease site within a juxtamembrane proteolytic switch domain to activate transcriptional programs. We created a Synthetic Notch Assay for Proteolytic Switches (SNAPS) that exploits the modularity and unequivocal input/response of Notch proteolysis to screen surface receptors for other putative proteolytic switches. We identify several new proteolytic switches among receptors with structural homology to Notch. We demonstrate SNAPS can detect shedding in chimeras of diverse cell surface receptors, leading to new, testable hypotheses. Finally, we establish the assay can be used to measure modulation of proteolysis by potential therapeutics and offer new mechanistic insights into how DECMA-1 disrupts cell adhesion.
Bibliographical noteFunding Information:
National Institute of General Medical Sciences R35 GM119483 Wendy R Gordon, Pew Charitable Trusts Pew Biomedical Scholar Wendy R Gordon National Cancer Institute U54CA210190 Eric J Aird Wendy R Gordon, 3M Graduate student fellowship Eric J Aird, American Heart Association Graduate student fellowship Amanda N Hayward, NIGMS T32GM008347 Eric J Aird.
© Hayward et al.