Figure 2.

The role of PPARγ in collagen signaling in platelets. GPVI stimulation with collagen leads to the recruitment and activation of Syk. Syk recruits and phosphorylates PPARγ, which in turn leads to the recruitment of LAT, resulting in enhanced signal transduction downstream of GPVI. PPARγ ligands prevent the interaction of PPARγ with the Syk signaling complex, which is necessary for enhanced signaling of Syk and LAT. Ligand-bound PPARγ can also interact with PKCα, preventing it from mediating dense granule release. Lastly, ligand-activated PPARγ prevents PPARγ phosphorylation and interaction with MAPK, an essential downstream mediator of collagen signaling.