HUK4, or Phospholipase D family member 3, is a human gene encoded by PLD3. It may also be known as: Phospholipase D3; PLD 3; Choline phosphatase 3; HindIII K4L homolog; Hu-K4; Phosphatidylcholine-hydrolyzing phospholipase D3; AD19; phospholipase D family, member 3. The encoded protein is an enzyme with an amino acid length of 490 and a mass of 54.7 kDa. Other isoforms may exist. HUK4 is a member of the Phospholipase D family. Homologs of this gene exist in other organisms, including: Mouse, Rat, Zebrafish.