Properties and modes of action of specific and non-specific phospholipid transfer proteins.
We have described the mode of action of the phosphatidylcholine transfer protein (PC-TP), the phosphatidylinositol transfer protein (PI-TP) and the non-specific lipid transfer protein (nsL-TP) isolated from bovine and rat tissues. PC-TP and PI-TP specifically bind one phospholipid molecule to be carried between membranes. PC-TP, and most likely PI-TP as well, have independent binding sites for the sn-1- and sn-2-fatty acyl chains. These sites have different properties, which may explain the ability of PC-TP and PI-TP to discriminate between positional phospholipid isomers. nsL-TP, which is identical to sterol carrier protein 2, transfers all common phospholipids, cholesterol and oxysterol derivatives between membranes. This protein is very efficient in mediating a net mass transfer of lipids to lipid-deficient membranes. Models for its mode of action, which is clearly different from that of PC-TP and PI-TP, are presented.
Centre for Biomembranes and Lipid Enzymology, State University of Utrecht, The Netherlands.
K W
KW
Wirtz
T W
TW
Gadella
D000818:Animals; D002352:Carrier Proteins / Q000502:physiology*; D002462:Cell Membrane / Q000502:physiology; D008565:Membrane Proteins / Q000502:physiology*; D049294:Phospholipid Transfer Proteins; D010743:Phospholipids / Q000494:pharmacology / Q000502:physiology*
D002352:Carrier Proteins; D008565:Membrane Proteins; D049294:Phospholipid Transfer Proteins; D010743:Phospholipids