Along with the structurally unrelated Sec14p family (found in Pfam:PF00650), this family can bind/exchange one molecule of phosphatidylinositol (PI) or phosphatidylcholine (PC) and thus aids their transfer between different membrane compartments. The ...
Along with the structurally unrelated Sec14p family (found in Pfam:PF00650), this family can bind/exchange one molecule of phosphatidylinositol (PI) or phosphatidylcholine (PC) and thus aids their transfer between different membrane compartments. There are three sub-families - all share an N-terminal PITP-like domain, whose sequence is highly conserved. It is described as consisting of three regions. The N-terminal region is thought to bind the lipid and contains two helices and an eight-stranded, mostly antiparallel beta-sheet. An intervening loop region, which is thought to play a role in protein-protein interactions, separates this from the C-terminal region, which exhibits the greatest sequence variation and may be involved in membrane binding. PITP alpha (Swiss:Q00169) has a 16-fold greater affinity for PI than PC. Together with PITP beta (Swiss:P48739), it is expressed ubiquitously in all tissues [1].
