You are studying fatty acid synthesis in a cell line isolated from a hepatic cancer patient. You discover that addition of glucose 6-phosphate does not lead to an increase in the rate of palmitic acid synthesis as is the situation for normal hepatic cells. This indicates there is a defect in the allosteric regulation of fatty acid synthase (FAS). Which of the following would most likely also be observed in these cells?
A) decreased cholesterol synthesis
B) decreased ketone synthesis
C) decreased protein synthesis
D) increased amino acid oxidation
E) increased glycogen synthesis

Question

Quizplus · Accepted Answer

Regulation of de novo fatty acid synthesis by phosphorylated sugars takes place via allosteric activation of the activity of FAS. Addition of glucose 6-phosphate (G6P) to cells would also result in changes in the level of allosteric regulation of phosphorylase and glycogen synthase. G6P is an allosteric inhibitor of phosphorylase and an activator of glycogen synthase, the net result therefore, would be an increased ability to store glycogen.

You Are Studying Fatty Acid Synthesis in a Cell Line