Current thoughts on the phosphatidylinositol transfer protein family

FEBS Letters

Allen-Baume, Victoria¹  Ségui, Bruno¹  Cockcroft, Shamshad¹ 

[1] Department of Physiology, University College London, London WC1E 6JJ, UK

关键词: Phospholipase C;    Phosphatidylinositol 3-kinase;    Phosphoinositide;    Membrane traffic;    Growth factor;    Lipid signaling;    PITP;    phosphatidylinositol transfer protein;    PI;    phosphatidylinositol;    PC;    phosphatidylcholine;    PC-TP;    PC transfer protein;    PI(4;    5)P2;    phosphatidylinositol 4;    5-bisphosphate;    PI(3;    4;    5)P3;    phosphatidylinositol 3;    4;    5-trisphosphate;    SM;    sphingomyelin;    SMase;    sphingomyelinase;    DAG;    diacylglycerol;    PLC;    phospholipase C;    FRET;    fluorescence resonance energy transfer;    PYK2;    a tyrosine kinase;   

DOI  :  10.1016/S0014-5793(02)03412-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Monomeric transport of lipids is carried out by a class of proteins that can shield a lipid from the aqueous environment by binding the lipid in a hydrophobic cavity. One such group of proteins is the phosphatidylinositol transfer proteins (PITP) that can bind phosphatidylinositol and phosphatidylcholine and transfer them from one membrane compartment to another. PITPs are found in both unicellular and multicellular organisms but not bacteria. In mice and humans, the PITP domain responsible for lipid transfer is found in five proteins, which can be classified into two classes based on sequence. Class I PITPs comprises two family members, α and β, small 35 kDa proteins with a single PITP domain which are ubiquitously expressed. Class IIA PITPs (RdgBαI and II) are larger proteins possessing additional domains that target the protein to membranes and are only able to bind lipids but not mediate transfer. Finally, Class IIB PITP (RdgBβ) is similar to Class I in size (38 kDa) and is also ubiquitously expressed. Class III PITPs, exemplified by the Sec14p family, are found in yeast and plants but are unrelated in sequence and structure to Class I and Class II PITPs. In this review we discuss whether PITP proteins are passive transporters or are regulated proteins that are able to couple their transport and binding properties to specific biological functions including inositol lipid signalling and membrane turnover.

【 授权许可】

Unknown