a -IGLK (Islet Glucokinase)

 Glucokinase, also termed Hexokinase D, is the characteristic isoenzyme of hexokinase in pancreatic islet ß-cells (IGLK, B-type GK; GKB) and in the liver (L-Type GK; GKL) that phosphorylates glucose at the sixth carbon position, thus committing glucose to the glycolytic pathway (1). The protein localizes to the outer membrane of mitochondria. In contrast with other forms of hexokinase, GK is not inhibited by its product (glucose-6-phosphate) but remains active while glucose is abundant. In B-type GK-containing cells, glucose is the predominant inducer of GK(2). Glucose-driven GK expression is modified by many positive and negative factors: it is augmented by cAMP, biotin, retinoic acid, PL, and insulin, and it is decreased by low cytosolic Ca2+ levels. Even though insulin is not sufficient to induce the enzyme, the hormone may still be required for optimal GK expression in B-type GK-containing cells (reviewed in 3). To date, over 150 GK gene mutations have been found that are manifest in at least three clearly distinguishable syndromes inherited in an autosomal dominant manner: 1) GK-linked persistent hyperinsulinemic hypoglycemia (PHHI-GK) (4); 2) GK-linked permanent neonatal diabetes (PNDM-GK) (5); and 3) GK-linked maturity- onset diabetes of the young (MODY-GK, also called MODY-2) (6). Recently, a novel class of drugs that stimulate the GK molecule directly have been discovered (7), which offer a new principle for drug therapy of diabetes.

Specificity
α-IGLK reacts with the IGLK protein in HeLa nuclear extract by Western Blotting. Recommended dilution range for Western blot analysis: 1:2000-1:5000. Recommended starting dilution: 1:2000.

Storage
Aliquot and store at -20°C.
 
References:
1. Bell GI, et al., 2002 Enc of Mol Med., p.1437 –1442
2. Liang Y, et al., 1992 Diabetes 41, 792 –806
3. Matchinsky, FM 2002, Diabetes 51, S394-S404
4. Glaser B, et al., 1998 N Engl J Med 338, 226 –230
5. Njolstad PR, et al., 2001. N Engl J Med 344, 1588 –1592
6. Froguel P, et al., 1993 N Engl J Med 328, 697 –702
7. Grimsby J, et al., 2001 Diabetes50 (Suppl. 2), A115