Synchronous behavior pattern of key glycolytic enzymes: Glucokinase, phosphofructokinase, and pyruvate kinase

Weber, George; Singhal, Radhey L.; Stamm, Nancy B.; Lea, Michael A.; Fisher, Elizabeth

doi:10.1016/0065-2571(66)90007-0

Cited by 183 publications

(50 citation statements)

References 26 publications

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“…From results of studies with alloxan diabetic rats, WEBER et al 1,2) suggested that insulin acts as a suppressor of hepatic gluconeogenic enzymes and as an inducer of hepatic glycolytic enzymes. However, INUI and YOKOTE3) reported that no appreciable changes were observed in liver fructose-1, 6-diphosphatase (FDPase) and phos phofructokinase (PFK) activities in insulin-in jected eel Anguilla japonica.…”

Section: Changes In Activities Of Hepatic Enzymes Related To Carbohydmentioning

confidence: 99%

Changes in activities of hepatic enzymes related to carbohydrate metabolism of fishes in glucose and insulin-glucose tolerance tests.

Furuichi¹,

Yone²

1982

NIPPON SUISAN GAKKAISHI

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In order to investigate the changes in activities of hepatic glycolytic and gluconeogenic en zymes after feeding and the responses of these enzymes to insulin injection , carp Cyprinus carpio, red sea bream Chrysophrys major, and yellowtail Serbia quinqueradiata were subjected to glucose tolerance and insulin-glucose tolerance tests after a 30-day feeding trial with diets containing 0% and 10% dextrin. Activities of glycolytic enzymes (hexokinase and PFK) and gluconeogenic enzymes (G6Pase and FDPase) increased after the administration of glucose in all species . The enzyme activities were intensified or restrained by the insulin injection. No significant differences between the fish species were recognized for hexokinase and G6Pase activities before or after the administration of glucose, nor for the response of the enzymes to the insulin injection. PFK ac tivity before and after the administration of glucose was lowest and its response to the insulin injection was highest in yellowtail, in which the optimum level of dietary dextrin was the lowest of the species tested. PFK of carp showed the highest activity and FDPase of carp showed the lowest activity before and after the administration of glucose.

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Section: Changes In Activities Of Hepatic Enzymes Related To Carbohydmentioning

confidence: 99%

Changes in activities of hepatic enzymes related to carbohydrate metabolism of fishes in glucose and insulin-glucose tolerance tests.

Furuichi¹,

Yone²

1982

NIPPON SUISAN GAKKAISHI

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“…PEP-carboxykinase and PFK are key enzymes of gluconeogenesis and glycolysis that show reciprocal changes in activity levels in fasted animals (3,4). We therefore assayed these enzymes in the livers and kidneys of the fasted and refed rabbits (Fig.…”

Section: Effects Of Fasting and Refeeding On The Activities Of Liver Andmentioning

confidence: 99%

“…Johnson et al (3) have shown that the gluconeogenic enzyme, PEP-carboxykinase, increases dramatically in the livers of fasted rabbits, while Weber et al (4) have reported profound decreases in the level of the key glycolytic enzyme, PFK, in livers of fasted rats. We have confirmed the reciprocal changes in activities of these two enzymes and found that after 36 hr the level of Fru-P2ase begins to rise and thereafter increases in parallel with that of PEP-carboxykinase.…”

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confidence: 99%

Changes in Activity and Molecular Properties of Fructose 1,6-Bisphosphatase During Fasting and Refeeding

Pontremoli¹,

Melloni²,

Salamino³

et al. 1974

Proc. Natl. Acad. Sci. U.S.A.

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During prolonged starvation, fructose 1,6-bisphosphatase (EC 3.1.3.11) activity in rabbit liver and kidney shows a transient decrease during the first 36 hr., before rising at 96 hr to levels severalfold higher than those found in the livers of fed animals. Proteolytic activity appears in the 105,000 X g supernatant fraction within several hours of starvation, and continues to increase during the entire 96-hr period. On refeeding, the activities return to nearly the control levels within 24 hr. The catalytic properties of fructose 1,6-bisphosphatase isolated from the livers of fasted rabbits are similar to those of the enzyme from fed animals, but its structure is modified, since it no longer contains the single tryptophan residue located near the NH2-terminus in the native enzyme. Thus this tryptophan residue is not required for the neutral pH optimum. The structural changes and the transient decrease in activity may be related to the observed increase in "free" proteolytic activity.

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“…In tissues such as liver and fat, insulin has long-term effects on the synthesis of certain enzymes regulating the intracellular metabolism of glucose (7)(8)(9). These effects are-believed to result from an increased production of messenger RNA (7,(10)(11)(12).…”

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Binding of insulin to isolated nuclei.

Goldfine¹,

Smith²

1976

Proc. Natl. Acad. Sci. U.S.A.

135

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(4)(5)(6).In tissues such as liver and fat, insulin has long-term effects on the synthesis of certain enzymes regulating the intracellular metabolism of glucose (7-9). These effects are-believed to result from an increased production of messenger RNA (7,(10)(11)(12) (27). Radioiodinated T3 (200,gCi/,ug) was purchased from Abbott Laboratories, and neutral-pH, carrier-free Na125I (300-500 mCi/ml) was purchased from New England Nuclear.Todination of Insulin and Glucagon. Insulin was radioiodinated by the stoichiometric chloramine-T technique under the conditions described for bovine thyrotropin (27). The initial concentrations of reactants were 15 MAM insulin, 30,gM Na251I, and 30,gM chloramine-T. After the preliminary purification step with Sephadex G-25 (27), the hormone was purified further on Sephadex G-50 (regular). This radioiodinated insulin (80-190 gCi/,gg) was 95-97% precipitable by 10% trichloroacetic acid and greater than 90% precipitable by excess insulin antibodies.Glucagon was radioiodinated as previously described (28). Preparation of Nuclei and Plasma Membranes. Nuclei were prepared by a'combination of the sucrose-density centrifugation (29, 30) and the Triton X-100 techniques (31). Female Sprague-Dawley rats, 80-120 g, fed ad lib, were anesthetized with ether and decapitated. After exsanguination the liver was rapidly removed, freed of connective tissue, placed in a chilled beaker, and minced. The following steps were performed at 4°. Ten grams of liver was added to 100 ml of buffer containing 0.25 M sucrose, 10 mM MgC12, and'20 mM Tris-HCI, pH 7.85 (STM buffer). The tissue was then homogenized with 10 strokes with a Potter-Elvehjem homogenizer (2000 rpm), filtered through four layers of cheesecloth, and centrifuged at 800 X g for 10 min. The pellet was then suspended in 60 ml of 2.2 M sucrose plus 1 mM MgCl2, divided into six portions, and centrifuged at 53,000 X g for 45 min. The combined pellets were then suspended in STM buffer plus 0.5% Triton X-100 (10 ml/g wet weight of liver) and centrifuged at

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Synchronous behavior pattern of key glycolytic enzymes: Glucokinase, phosphofructokinase, and pyruvate kinase

Cited by 183 publications

References 26 publications

Changes in activities of hepatic enzymes related to carbohydrate metabolism of fishes in glucose and insulin-glucose tolerance tests.

Changes in activities of hepatic enzymes related to carbohydrate metabolism of fishes in glucose and insulin-glucose tolerance tests.

Changes in Activity and Molecular Properties of Fructose 1,6-Bisphosphatase During Fasting and Refeeding

Binding of insulin to isolated nuclei.

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