What activates PFK-1?

PFK-1, or phosphofructokinase-1, is a key regulatory enzyme in glycolysis. Its activity is significantly influenced by the levels of certain metabolites in the cell. The correct activators of PFK-1 include AMP and fructose 2,6-bisphosphate.

AMP, or adenosine monophosphate, serves as an indicator of low energy status within the cell. When ATP levels are low, indicating energy depletion, AMP levels rise. This shift prompts PFK-1 to increase its activity, promoting glycolysis to generate more ATP.

Fructose 2,6-bisphosphate is a potent allosteric effector that dramatically enhances the activity of PFK-1. Its levels are regulated by insulin and glucagon signaling, linking PFK-1 activity directly to the energy needs of the cell. When fructose 2,6-bisphosphate concentration is high, it strongly promotes PFK-1 activity, further driving glycolysis.

In contrast, ATP acts as an inhibitor of PFK-1, signaling that the energy needs of the cell are met, while citrate also serves as an inhibitor, indicating that there is sufficient biosynthesis occurring. Thus, AMP