Analysis of glucose-6-phosphate translocase and hexose-6-phosphate phosphohydrolase, the two obligatory components of microsomal glucose-6-phosphatase system, in rat liver.
A membrane filter procedure developed by Igarashi et al. (1984) for the measurement of glucose 6-phosphate uptake by the microsomes has been demonstrated to be a good method for assaying glucose-6-phosphate translocase, an obligatory component of the microsomal glucose-6-phosphatase system. When glucose-6-phosphate translocase was assayed in developing and diabetic rat livers independently of hexose-6-phosphate phosphohydrolase, another obligatory component of the glucose-6-phosphatase system, the two activities were found to undergo alterations, whose profiles, however, were quite distinct from each other. The profile of the microsomal glucose-6-phosphatase activity resembles the profile of the phosphohydrolase activity rather than that of the translocase activity, suggesting that the phosphohydrolase may be rate-limiting at least under these conditions. AH-109A, a strain of transplantable rat ascites hepatoma, was found to lack both glucose-6-phosphate translocase and hexose-6-phosphate phosphohydrolase activities.
Hata
K
K
Biochemistry Laboratory, Tohoku University, Sendai.
Kikuchi
K
K
Tada
K
K
Tsuiki
S
S
D000375:Aging; D000818:Animals; D000831:Animals, Newborn; D017920:Antiporters; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology; D005333:Fetus; D005952:Glucose-6-Phosphatase / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000254:growth & development; D008114:Liver Neoplasms, Experimental / Q000201:enzymology; D008862:Microsomes, Liver / Q000201:enzymology*; D009004:Monosaccharide Transport Proteins; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D010770:Phosphotransferases / Q000378:metabolism*; D011732:Pyridoxal Phosphate / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D017920:Antiporters; D009004:Monosaccharide Transport Proteins; C503533:Slc37a4 protein, rat; C111261:glucose 6-phosphate(transporter); D011732:Pyridoxal Phosphate; D010770:Phosphotransferases; D010744:Phosphoric Monoester Hydrolases; C022700:sugar-phosphatase; D005952:Glucose-6-Phosphatase