Glucose transporters (GLUT and SGLT): expanded families of Glucose transporter proteins: Diabetes mellitus: Adipose tissue: Muscle: Sugar transport. Glucose transporter 1 (or GLUT1), also known as solute carrier family 2, facilitated glucose transporter member 1 (SLC2A1), is a uniporter protein that in humans. Sodium-dependent glucose cotransporters are a family of glucose transporter found in the intestinal mucosa (enterocytes) of the small intestine (SGLT1) and the.
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The encoded protein is found primarily in the cell membrane and on the cell surface, where it can also function as a receptor for human T-cell leukemia virus HTLV I and II.
Sodium-glucose transport proteins
GLUT1 was the first glucose transporter to be characterized. GLUT 1 is highly conserved. The SLC2A1 gene is located on the p arm of chromosome 1 in position GLUT1 behaves as a Michaelis-Menten enzyme and contains 12 membrane-spanning alpha heliceseach containing 20 amino acid residues. A helical wheel analysis shows that the membrane spanning alpha helices are amphipathicwith one side being polar and the other side hydrophobic.
Six of these membrane spanning helices are believed to bind together in the membrane to create a polar channel in the center through which glucose can traverse, with the hydrophobic regions on the outside of the channel adjacent to the fatty acid tails of the membrane. Energy-yielding metabolism in erythrocytes depends on a constant supply of glucose from the blood plasmawhere the glucose concentration is maintained at about 5mM.
Sodium-glucose transport proteins – Wikipedia
Glucose enters the erythrocyte by facilitated diffusion via a specific glucose transporter, at a rate about 50, times greater than uncatalyzed transmembrane diffusion. The glucose transporter of erythrocytes glujosa GLUT1 to distinguish it from related glucose transporters in other tissues transportre a type III integral protein with 12 hydrophobic segments, each of which is believed to form a membrane-spanning g,ukosa.
The detailed structure gkukosa GLUT1 is not known yet, but one plausible model suggests that the side-by-side assembly of several helices produces a transmembrane channel lined with hydrophilic residues that can hydrogen-bond with glucose as it moves through the channel.
GLUT1 is responsible for the low level of basal glucose uptake required to sustain respiration in all cells. Expression levels of GLUT1 in cell membranes are increased by reduced glucose levels and decreased by increased glucose levels. GLUT1 is also a major receptor for uptake of Vitamin C as well as glucoseespecially in non vitamin C producing mammals as part of an adaptation to compensate by participating in a Vitamin C recycling process.
GLUT1 expression occurs in almost all tissues, with the degree of expression typically correlating with the rate of cellular glucose metabolism. In the adult it is expressed at highest levels in erythrocytes and also in the endothelial cells of barrier tissues such as the blood—brain barrier.
This disease can be inherited in either an autosomal recessive or autosomal dominant manner. Onset of seizuresusually characterized by apneic episodesstaring spells, and episodic eye movementsoccurs within the first 4 months of life. Other paroxysmal findings include intermittent ataxiaconfusionlethargysleep disturbanceand headache. Varying degrees of cognitive impairment transpirter occur, ranging from learning disabilities to severe mental retardation.
The dyskinesia involves transient abnormal involuntary movementssuch as dystonia and choreoathetosisinduced by exercise or exertion, and affecting the exercised limbs.
The GLUT4 glucose transporter.
Some patients may also have epilepsymost commonly childhood absence epilepsy. Mild mental retardation may also occur. In some patients involuntary exertion-induced dystonic, choreoathetotic, and ballistic movements may be associated with macrocytic hemolytic anemia.
Generalized seizures arise diffusely and simultaneously from both hemispheres of the brain. Seizure types include juvenile myoclonic seizuresabsence seizuresand generalized tonic-clonic seizures. In some EIG12 patients seizures may remit with age.
Another mutation, ARGCYS, has been shown to cause Dystonia 9 DYT9an autosomal dominant neurologic disorder characterized by childhood onset of paroxysmal choreoathetosis and progressive spastic paraplegia. Most patients show some degree of cognitive impairment.
Other variable features may include seizures, migraine headaches, and ataxia. Glut1 has also been demonstrated as a powerful histochemical marker for hemangioma of infancy .
GLUT1 has two significant types in brain 45k and 55k. Fasentin is a small molecule inhibitor of glukpsa intracellular domain of GLUT1 preventing glucose uptake. Click on genes, proteins and metabolites below to link to respective articles. This article incorporates text from the United States National Library of Medicinewhich is in the public domain. From Wikipedia, the free encyclopedia.
Chromosome 1 human . Annual Review of Nutrition.
Glucose 6-phosphatase – Wikipedia
This article incorporates text from this source, which is in the public domain. This article incorporates text available under the CC BY 4. Molecular Aspects of Medicine. Lehninger, Tarnsporter of Biochemistry. Lay summary — ScienceDaily March 21, Molecular Biology of the Cell.
The Journal of Biological Chemistry. Biochimica et Biophysica Acta.
Journal of Child Neurology. Membrane proteinscarrier proteins: Vesicular glutamate transporter 1 SLC32A1. Mitochondria portal Gene Wiki portal. Retrieved from ” https: Genes on human chromosome 1 Membrane biology Integral membrane proteins Solute carrier family. Articles with imported freely licensed text Pages with DOIs inactive since Wikipedia articles needing page number citations from November All articles with unsourced statements Articles with unsourced statements from November Wikipedia articles incorporating text from the United States Transportet Library of Medicine.
By group SLC1—10 1: