Movie S1.

PI(4,5)P₂ depletion in isolated HeLa cells. Spinning-disc confocal microscope (SDC) movie of HeLa cells co-transfected with the PI(4,5)P₂ probe iRFP-PH-PLCδ1 and M₁ untagged muscarinic acetylcholine receptor (M₁R). Cells were imaged every 30 seconds. After 3 to 5 minutes after Oxo-M addition, cells were treated with 50 μM Atropine.