The mechanism of calcium-induced inhibition of muscle fructose 1,6-bisphosphatase and destabilization of glyconeogenic complex.
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ABSTRACT:
SUBMITTER: Rakus D
PROVIDER: S-EPMC3795747 | biostudies-literature | 2013
REPOSITORIES: biostudies-literature
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The mechanism of calcium-induced inhibition of muscle fructose 1,6-bisphosphatase and destabilization of glyconeogenic complex.
Rakus Dariusz D Rakus Dariusz D Gizak Agnieszka A Kasprzak Andrzej A AA Zarzycki Marek M Maciaszczyk-Dziubinska Ewa E Dzugaj Andrzej A
PloS one 20131011 10
The mechanism by which calcium inhibits the activity of muscle fructose 1,6-bisphosphatase (FBPase) and destabilizes its interaction with aldolase, regulating glycogen synthesis from non-carbohydrates in skeletal muscle is poorly understood. In the current paper, we demonstrate evidence that Ca(2+) affects conformation of the catalytic loop 52-72 of muscle FBPase and inhibits its activity by competing with activatory divalent cations, e.g. Mg(2+) and Zn(2+). We also propose the molecular mechani ...[more]
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