Protein folding lipid-binding proteins

Detailed protein structures have been reported for BPI and CETP. Given the aforementioned similarities within this gene family, these protein structures serve as a likely model for the protein structure of PLTP. CETP and BPI are elongated molecules, shaped like a boomerang. There are two domains with similar folds, and a central beta-sheet domain between these two domains. The molecules contain two lipid-binding sites, one in each domain near the interface of the barrels and the central beta-sheet. 

Palmitoylation is, after myristoylation, the most common modification of the a-sub-rmit of the heterotrimeric G-proteins (see chapter 5). The a-subunit of G-proteins can be lipidated in a two-fold marmer, with a myristoic acid and a pahnitoic acid anchor at the N-terminus. It appears in this case that two lipid anchors are necessary to mediate a stable association of the protein with the membrane. The lipidation of cytoplasmic protein tyrosine kinase also includes both myristoylation and palmitoylation. H-Ras protein also requires, apart from C-terminal farnesylation (see below), a pahnitoyl modification in order to bind to the plasma membrane. In all mentioned examples the fatty acid anchors play an essential role in the signal transduction. 

---