Muniyappa K, Leibach F H, Mendicino J
Life Sci. 1983 Jan 17;32(3):271-8. doi: 10.1016/0024-3205(83)90040-1.
The effect of fructose 2,6-P2, AMP and substrates on the coordinate inhibition of FBPase and activation of PFK in swine kidney has been examined. Fructose 2,6-P2 inhibits the activity of FBPase and stimulates the activity of PFK in the presence of inhibitory concentrations of ATP. Under similar conditions 2.2 microM fructose 2,6-P2 was required for 50% inhibition of FBPase and 0.04 microM fructose 2,6-P2 restored 50% of the activity of PFK. Fructose 2,6-P2 also enhanced the allosteric activation of PFK by AMP and it increased the extent of inhibition of FBPase by AMP. Fructose 2,6-P2, AMP and fructose 6-P act cooperatively to stimulate the activity of PFK whereas the same latter two effectors and fructose 1,6-P2 inhibit the activity of FBPase. Taken collectively, these results suggest that an increase in the intracellular level of fructose 2,6-P2 during gluconeogenesis could effectively overcome the inhibition of PFK by ATP and simultaneously inactivate FBPase. When the level of fructose 2,6-P2 is low, a glycolytic state would be restored, since under these conditions PFK would be inhibited by ATP and FBPase would be active.
研究了果糖2,6 -二磷酸、AMP和底物对猪肾中果糖-1,6-二磷酸酶（FBPase）协同抑制作用及磷酸果糖激酶（PFK）激活作用的影响。在存在抑制浓度ATP的情况下，果糖2,6 -二磷酸抑制FBPase的活性并刺激PFK的活性。在类似条件下，50%抑制FBPase需要2.2微摩尔/升的果糖2,6 -二磷酸，而0.04微摩尔/升的果糖2,6 -二磷酸可恢复50%的PFK活性。果糖2,6 -二磷酸还增强了AMP对PFK的变构激活作用，并增加了AMP对FBPase的抑制程度。果糖2,6 -二磷酸、AMP和果糖6 -磷酸协同作用刺激PFK的活性，而后两者与果糖1,6 -二磷酸则抑制FBPase的活性。综合来看，这些结果表明在糖异生过程中细胞内果糖2,6 -二磷酸水平的升高可有效克服ATP对PFK的抑制作用，并同时使FBPase失活。当果糖2,6 -二磷酸水平较低时，糖酵解状态将恢复，因为在这些条件下PFK会被ATP抑制，而FBPase将具有活性。
