Adipocyte lipid-binding protein structure

Following is a somewhat idealized description of how map fitting may proceed, illustrated with views from a modern map-fitting program. The maps and models are from the structure determination of adipocyte lipid binding protein (ALBP), which I will discuss further in Chapter 8. 

Z. Xu, D. A. Bemlohr, and L. J. Banaszak, Crystal structure of recombinant murine adipocyte lipid-binding protein, Biochemistry 31,3484-3492, 1992. 

Adipocyte lipid-binding protein (ALBP) is the adipocyte member of an intracellular hydrophobic ligand-binding protein family. ALBP is phosphorylated by the insulin receptor kinase upon insulin stimulation. The crystal structure of recombinant murine ALBP has been determined and refined to 2.5 A. The final R-factorfor the model is 0.18 with good canonical properties. 

Reese-Wagoner, A., et al., Structural properties of the adipocyte lipid binding protein. Biochim Biophys Acta, 1999, 1441, 106-116. 

Figure 22 Introducing nonnative prosthetic group into metalloproteins. (a) by chemical modification of heme propionate. (Reprinted with permission from Ref. 25. 2002 the American Chemical Society) (b) by noncovalent addition strategy. The crystal structure of the Fe (3,3 -Me2-salophen) incorporated into Alal7GlaMb. (Reprinted with permission from Ref. 287. 2004 the American Chemical Society) (c) by a single attachment strategy. The computer model of adipocyte lipid binding protein-phenanthrolme complex. (Reprinted with permission from Ref. 291. 1997 the American Chemical Society) (d) by a dual covalent attachment strategy. The computer model of Mb(L72CA 103C) with a Mn -Salen complex covalently attached at two-points and overlayed with heme. (Reprinted with permission from Ref. 288. 2004 the American Chemical Society)...

Caveoiae represent a subset of lipid rafts found on specific cell types, including adipocytes, endothelia, and muscle cells. These lipid rafts can be observed by electron microscopy as distinctive flask-shaped pits of 60 nm in diameter and include proteins of the caveolin family on the cytoplasmic face of the pit. Lymphocytes and many neuronal cells do not express caveolins and lack these morphological membrane features. Although caveoiae are considered relatively static structures on the cell surface, they can become internalized on binding of... 

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