Regulation of PLD by the M3 muscarinic receptor and receptor tyrosine kinases in HEK-293 cells. In human embryonic kidney (HEK-293) cells, signaling to PLD by the M3 muscarinic receptor and by typical RTKs (EGF, PDGF, insulin) is organized into rather discrete pathways and channeled by particular heterotrimeric G proteins and small GTPases (orange), specific GEF proteins (pink) and further signaling components (green). AC, adenylyl cyclase; ROCK, Rho-kinase