| We found that ADP ribosylation factor 4 ( ARF 4 ) interacts with the intracellular part of EGFR and mediates the EGF dependent cellular activation of phospholipase D 2 ( PLD 2 ) but does not mediate the activation of PLD 1 . ^^^ ADP ribosylation factor 4 small GTPase mediates epidermal growth factor receptor dependent phospholipase D 2 activation . ^^^ |