Rate-limiting Enzymes Flashcards
What up regulates PFK-1?
AMP
What two factors down regulate PFK-1?
Hint: PFK-1 is the rate limiting step of glycolysis
High levels of ATP and Citrate
This tells us we have high energy molecules, so there is no point in up regulating glycolysis to get extra energy.
What factor up regulates the enzyme isocitrate dehydrogenase?
Hint: This enzyme is the rate limiting step of the Krebs Cycle
High levels of ADP.
This is a lower energy molecule, so it makes sense that high levels of it will jump start the Krebs Cycle to make more energy.
What two factors down regulate isocitrate dehydrogenase?
Hint: This enzyme is the rate limiting step of the Krebs Cycle
High levels of ATP and NADH.
This tells us we have enough energy and “fuel” for the ETC to make energy.
What down regulates fructose-1,6-bisphosphatase?
Hint: This enzyme is the rate limiting step of the Gluconeogenesis
AMP.
What three factors up regulate the activity of glycogen synthase?
Hint: This enzyme is the rate limiting step of Glycogenesis.
G6P, insulin, and cortisol.
What two factors down regulate glycogen synthase?
Hint: This enzyme is the rate limiting step of Glycogenesis.
Epinephrine and glucagon.
What three factors up regulates the enzyme glycogen phosphorylase?
Hint: This enzyme is the rate limiting step of Glycogenolysis.
Epinephrine, glucagon, and AMP.
What three factors down regulates the enzyme glycogen phosphorylase?
Hint: This enzyme is the rate limiting step of Glycogenolysis.
G6P, insulin, and ATP.
What up regulates the enzyme glucose-6P-dehydrogenase?
Hint: This enzyme is the rate limiting step of the Pentose Phosphate Pathway.
NADP+
What down regulates the enzyme glucose-6P-dehydrogenase?
Hint: This enzyme is the rate limiting step of the Pentose Phosphate Pathway.
NADPH.
