Hydrogen deuterium exchange mass spectrometry (HDX-MS) was used to analyze how the mini-SHIP1 construct interacts with receptor-derived phosphotryrosine peptides (pY) to probe how these peptides regulate SHIP1 autoinhibition. This HDX-MS helped to identify intramolecular contacts involved in the regulation of SHIP1 autoinibition. Results from this HDX analyzing the monomeric mini-SHIP1 construct are used in tandem with HDX-MS results analyzing the a dimeric SHIP1 construct to confirm the same mechanism of autoinhibtion exists. These results help confirm autoinhibition of monomeric SHIP1 is indeed likely regulated by the same mechanism to that of dimeric SHIP1.