Glucose transporter proteins

FIGURE 10.5 A model for the arrangement of the glucose transport protein in the erythrocyte membrane. Hydropathy analysis is consistent with 12 transmembrane helical segments. 

The structure of the human erythrocyte glucose transport protein... 

Vannucci, S. J., Maher, F. and Simpson, I. A. Glucose transporter proteins in brain delivery of glucose to neurons and glia. Gfia 21 2-21,1997. 

Defective transport of glucose across the blood-brain barrier is caused by deficiency in the glucose transporter protein 703... 

Maher F, Vannucci SJ, Simpson IA (1994) Glucose transporter proteins in brain. FASEB Journal 8 1003-1011... 

Il.f.l.1. Insulins. Insulin is the most effective of diabetes medications. Insulin has profound effects on carbohydrate, protein, fat metabolism and electrolytes. It has anabolic and anticatabolic actions. In a state of insulin deficiency, glycogenesis, glucose transport, protein synthesis, triglyceride synthesis, LPL activity in adipose tissue, cellular potassium uptake all decrease on the other hand, gluconeogene-sis, glycogenolysis, protein degradation, ketogene-sis, lipolysis increase. 

Glucose transport into skeletal muscle cells via insulin-dependent glucose transport proteins in the plasma membrane (see p. 95) and subsequent glucose metabolism are depressed because of low levels of circulating insulin. 

The uptake of glucose by brain, liver, kidneys, erythrocytes, and the islets of Langerhans is unaffected by insulin. However, in muscle and adipose tissues insulin stimulates glucose uptake. Part of this effect results from insulin-induced translocation of molecules of the 509-residue glucose transport protein GLUT4 (Chapter 8) from the cytosol into the plasma membrane where it can function.354-3563 Insulin apparently also increases the rate of synthesis of the transporters. 

Jiang, J., Skelly, P.J., Shoemaker, C.B. and Caulfield, J.P. (1996) Schistosoma mansoni the glucose transport protein SGTP4 is present in tegumental multilamellar bodies, discoid bodies and the surface lipid bilayers. Experimental Parasitology 82, 201-210. 

Skelly, P.J., Kim, J.W., Cunningham, J. and Shoemaker, C.B. (1994) Cloning, characterization, and functional expression of cDNAs encoding glucose transporter proteins from the human parasite Schistosoma man-soni. Journal of Biological Chemistry 269, 4247-4253. 

Glucose Transporter Protein Syndromes Darryl C. De Vivo, Dong Wang,... 

Waddell ID, Zomerschoe AG, Voice MW, Burchell A (1992), Cloning and expression of a hepatic microsomal glucose transport protein, Biochem. J. 286 173-177. 

Insulin stimulates glucose transport into muscle and adipose cells by causing glucose transport proteins within cells to move to the cell membrane (see Table 5-1). 

Our understanding of the fundamental mechanism underlying the complex regulation of glucose homoeostasis has been dramatically transformed recently by the realization that glucose transport in mammalian tissues is mediated by a family of structurally related, but genetically distinct, glucose transporter proteins. This, however, will be discussed in detail later. 

Fig. 11. Model of the glucose-transporter protein integrated into the plasma membrane.

The properties of glucose transporter proteins (GLUT) consist of tissue specificity and differences in functional properties reflected in their glucose metabolism. Five transporter proteins. Glut 1-5, have been identified... 

R. A. Fishman The glucose-transporter protein and glucopenic brain injury. New England Journal of Medicine 325,731 (1991). 

Microsomal glucose transport protein (GLUT ), which is a member of the family of facilitative glucose transport proteins (Chapter 13) and which transports glucose into the cytosol. 

Several types of glucose transport proteins appear on specific tissues affecting the movement of glucose across cell membranes. 

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