Integrated phosphoproteomic profiling and causal analysis reveal signaling relations in GPVI/ITAM-mediated platelet activation programs

ABSTRACT: Platelets engage cues of pending endothelial dysfunction through coordinated adhesion, secretion and aggregation responses. These rapid changes in platelet phenotype are orchestrated by intracellular mechanisms that remain systematically undefined. This study develops a TMT-SPS-MS3 phosphoproteomics workflow to detail ~3,800 significant protein phosphorylation events associated with the progression of ITAM-mediated activation programs initiated by the platelet collagen receptor GPVI. With literature-guided causal inference tools, >200 site-specific signaling relations are mapped from phosphoproteomics data among key GPVI effectors (i.e., Syk, PLC gamma 2, PKC delta) and less characterized targets, including several Ras/MAPK axis proteins (i.e., KSR1). Networks highly regulated in GPVI/ITAM signaling out of context of curated knowledge are also highlighted, including Rab GTPase systems. In addition to serving as a model for generating and testing hypotheses from omics datasets, this study puts forth a means to identify hemostatic effectors and biomarkers relevant to thrombosis, vascular inflammation and other platelet-associated disease states.

INSTRUMENT(S): Orbitrap Fusion ETD

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Blood Platelet, Platelet

DISEASE(S): Cardiovascular System Disease

SUBMITTER: Phillip Wilmarth  

LAB HEAD: Dr. Joseph E. Aslan

PROVIDER: PXD017167 | Pride | 2020-11-20

REPOSITORIES: Pride