Phosphatidylinositol binding domains

TLR-2. Evidence for the bridging role of Mai comes from the presence of a phosphatidylinositol 4,5-bisphosphate (PEP2) binding domain at its N-terminus. This domain recruits Mai to areas of the plasma membrane rich in PEP2 and these areas have been shown to contain TLR-4. 

Welters, R Takegawa, K. Emr, S.D. Chrispeels, M.J. AtVPS34, a phosphatidylinositol 3-kinase of Arabidopsis thaliana, is an essential protein with homology to a calcium-dependent lipid binding domain. Proc. Natl. Acad. Sci. USA, 91, 11398-11402 (1994)... 

Mammalian PLDs are now the subject of intense interest as they appear to be intimately involved in signal transduction (M. McDermott, 2004 G.M. Jenkins, 2005). Two mammalian PLDs have been identified and these contain several domains often associated with signal transduction proteins including a PH domain and a separate phosphatidylinositol-bis-phosphate-binding domain. PLC and PLD that act on glycosylphosphatidylinositol-anchored proteins on the cell surface are of growing importance and are discussed in Chapter 2. 

The FYVE domain is a phosphatidylinositol-3-phosphate-binding module of approximately 60 to 80 amino acids. It was named after the first four proteins, where this domain was described (Fablp, YOTB, Vaclp and EEA1). 

Pleckstrin homology domain (PH-domain) was first identified at the amino and carboxyl termini of a haematopoietic protein called pleckstrin. PH-domain, a protein region of approximately 120 amino acids, by binding to phosphatidylinositol lipids of the biological membranes induces the translocation of the PH-domain containing protein to membrane compartment. Various PH-domains possess specificities for phosphoinositides phosphorylated at different sites within the inositol ring. 

Membrane associations can occur by selective protein binding to lipid head groups. One example is spectrin, which binds to phosphatidylinositol-4,5-bisphosphate by means of a pleckstrin-homology (PH) domain [5] (Fig. 2-5). and also to phosphatidyl serine [6] (Fig. 2-6). 

Fukazawa, T., K. A. Reedquist, T. Trub, S. Soltoff, G. Panchamoorthy, B. Druker, L. Cantley, S. E. Shoelson, and H. Band. The SH3 domain-binding T cell tyrosyl phosphoprotein pl20. Demonstration of its identity with the c-cbl protooncogene product and in vivo complexes with Fyn, Grb2, and phosphatidylinositol 3-kinase. J Biol Chem. 270 19141-50.1995. 

G.E. Gibbs, E.M. Potent activation of phosphatidylinositol 3-kinase by simple phosphotyrosine peptides derived from insulin receptor substrate 1 containing two YMXM motifs for binding SH2 domains. Biochemistry, 33, 9376-9381 (1994)... 

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