Module 2: Figure PLD isoforms
The domain structure of phospholipase D (PLD).
The two isoforms of phospholipase D (PLD) have similar domain structures. Palmitoylation of Cys-240 and Cys-241 within the pleckstrin homology (PH) domain play a critical role in localizing the enzyme to membranes. There are four conserved sequences (I–IV). Domains II and IV contain HXKXXXXD, the so-called HKD motif, which come together to form the catalytic domain. The C-terminal region has a phox homology (PX) domain and a PH domain responsible for the binding of PtdIns4,5P2 during activation of the enzyme (Module 2: Figure PLD signalling).