The recent identification of cDNA clones for phospholipase D1 and 2 has ope
ned the door to new studies on its structure and regulation. PLD activity i
s encoded by at least two different genes that contain catalytic domains th
at relate their mechanism of action to phosphodiesterases. In vivo roles fo
r PLD suggest that it may be important for multiple specialized steps in re
ceptor dependent and constitutive processes of secretion, endocytosis, and
membrane biogenesis. (C) 1999 Elsevier Science B.V. All rights reserved.