Lipid-binding proteins intracellular

Barrett, J., Saghir, N., Timanova, A., Clarke, K and Brophy, P.M. (1997) Characterisation and properties of an intracellular lipid-binding protein from the tapeworm Moniezia expansa. European Journal of Biochemistry 250, 269-275. 

Simpson, MA, LiCata, V.J., Coe, N.R. and Bernlohr, D.A. (1999) Biochemical and biophysical analysis of the intracellular lipid binding proteins of adipocytes. Molecular and Cellular Biochemistry 192, 33—40. 

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. 

Kane, C. D.,Coe, N. R., Vanlandingham, B., Krieg, P., Bernlohr, D. A. (1996). Expression purification, and ligandbinding analysis of recombinant keratinocyte lipid-binding protein (MAL-1), an intracellular lipid-binding found overexpressed in neoplastic skin cells. Biochemistry 35, 2894-2900. 

Bemlohr, D., Simpson, M Hertitel, A., and Banaszak, L- J. (1997). Intracellular lipid-binding proteins and their genes. Atmis. Reu. WuJr. 17,277-303. 

III. Conformational Similarity among Intracellular Lipid-Binding Proteins... 

D.A. Bernlohr, M.A. Simpson, A. Vogel Hertzel, and L.J. Banaszak, Intracellular lipid-binding proteins and their genes, Annu. Rev. Nutr., 1997, 17, 277-303. 

R 168 C. Lucke, L.H. Gutierrez-Gonzalez and J.A. Hamilton, Intracellular Lipid Binding Proteins Evolution, Structure, and Ligand Binding , p. 95... 

The Role of Myosins in Cell Locomotion The Role of Actin-Binding Proteins in Cell Locomotion The Transduction of Extracellular Motility Signals to the Cytoskeleton Lipid Flow and Cell Locomotion The Role of Cell Locomotion in Metastasis Intracellular Motility Microtubule-Based Intracellular Motility... 

The remaining major classes of water-soluble lipid transporter proteins (other than the polyproteins of nematodes see below) come from plants and helminths. Plants possess very small (approximately 9 kDa) helix-rich, fatty-acid-binding proteins, the structures of some of which are known (Lerche and Poulsen, 1998). A recently described class comes from cestodes these are also very small (approximately 8 kDa), presumably intracellular, and helix-rich, and bind anthelmintic drugs in addition to fatty acids (Janssen and Barrett, 1995 Barrett et al., 1997). The only helix-rich small (approximately 14 kDa) lipid transporter from vertebrates is the acetyl-CoA-binding protein (Kragelund et al., 1993). 

Schnurr et al. [22] showed that rabbit 15-LOX oxidized beef heart submitochondrial particles to form phospholipid-bound hydroperoxy- and keto-polyenoic fatty acids and induced the oxidative modification of membrane proteins. It was also found that the total oxygen uptake significantly exceeded the formation of oxygenated polyenoic acids supposedly due to the formation of hydroxyl radicals by the reaction of ubiquinone with lipid 15-LOX-derived hydroperoxides. However, it is impossible to agree with this proposal because it is known for a long time [23] that quinones cannot catalyze the formation of hydroxyl radicals by the Fenton reaction. Oxidation of intracellular unsaturated acids (for example, linoleic and arachidonic acids) by lipoxygenases can be suppressed by fatty acid binding proteins [24]. 

In many eukaryotic plasma membranes, PS resides in the inner leaflet (Schroit and Zwaal, 1991 Zachowski, 1993). This transbilayer distribution of membrane hpids is not a static situation but a result of balance between the inward and outward translocation of phospholipids across the membranes. Recent studies showed that the transbilayer lipid asymmetry is regulated by several lipid transporter proteins, such as aminophospholipid translocase (Daleke and Lyles, 2000), ATP-binding cassette transporter family (van Helvoort et al, 1996 Klein et al, 1999), and phospholipid scramblase (Zhou et al, 1997 Zhao et al, 1998). An increment of intracellular due to cell activation, cell injury, and apoptosis affects the activities of these transporters, resulting in exposure of PS (Koopman et al, 1994 Verhoven et al, 1995) and PE (Emoto et al, 1997) on the cell surface. 

Once formed, 1,25-DHCC acts on duodenal epithelial cells as a lipid-soluble hormone. Its intracellular receptor (a Zn-finger protein) binds to response elements in enhancer regions of DNA to induce the synthesis of calcium-binding proteins thought to play a role in stimulating calcium uptake from the GI tract. 

Synergy with catecholamines. The lipid soluble steroid molecules enter cells and bind the intracellular receptors. This results in up-regulation of specific genes, changes in RNA production, and protein synthesis. 

Most important for the regulation of the membrane architecture are membrane potential, intracellular Ca2+ concentration, pH, changes in lipid composition due to the action of phospholipases and cell-cell coupling as well as the coupling of the membrane to the cytoskeleton and the extracellular matrix. Membrane architecture is additionally modulated by ions, lipo- and amphiphilic hormones, metabolites, drugs, lipid-binding peptide hormones, and amphitropic proteins [44]. 

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