Which statement regarding regulation of glycolysis and gluconeogenesis is FALSE?
A) Phosphofructokinase-1 and fructose 1,6-bisphosphatase are prevented from forming a futile cycle by reversible covalent modification.
B) Hexokinase IV and glucose 6-phosphatase are transcriptionally regulated in hepatocytes.
C) Phosphofructokinase-1 and fructose 1,6-bisphosphatase are reciprocally regulated by the allosteric regulator, fructose 2,6-bisphosphate.
D) Binding of fructose 2,6-bisphosphate to phosphofructokinase-1 reduces the affinity of this enzyme for citrate.
E) The cellular concentration of fructose 2,6-bisphosphate is determined by a bifunctional enzyme that is hormonally regulated.

Question

Quizplus · Accepted Answer

Phosphofructokinase-1 and fructose 1,6-bisphosphatase are regulated through allosteric mechanisms and reciprocal control by fructose 2,6-bisphosphate, not by reversible covalent modification. This ensures that glycolysis and gluconeogenesis do not counteract each other inefficiently in a futile cycle.

Which Statement Regarding Regulation of Glycolysis and Gluconeogenesis Is FALSE