Figure 3. TRAX competes with Gα_q for PLCβ1 binding but not membranes.

A – Binding of PLCβ1 to 2 nM activated CPM- Gα_q(GTPγS) in the absence (•) and presence (○) of 200 nM TRAX right panel showing the loss in Gα_q affinity when TRAX is present, where n = 6 and S.D. is shown. We note that an ∼20% increase in CPM intensity was seen both without and with TRAX. B- Binding of PLCβ1 to 2 nM deactivated CPM- Gα_q(GDP) in the absence (•) and presence (○) of 200 nM TRAX, where n = 3 and S.D. is shown. C- Binding of PLCβ1 to PC∶PS∶PE (1∶1∶1) large, unilamellar vesicles in the absence (•) (K_p = 132 µM) and presence (○) (K_p = 120 µM) of 200 nM TRAX as measured by the increase in CPM intensity as LUVs are titrated into the solution, where n = 3 and S.D. is shown.