system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Malate shuttle is important in ________
assistant
The correct answer is  NADH cannot penetrate the mitochondrial membrane, but it is produced continuously in the cytosol by 3-phosphoglyceraldehyde dehydrogenase, an enzyme in the glycolysis sequence.
The transfer of reducing equivalents is carried out by using the various shuttle systems.
Malate shuttle system is of more universal utility. Used to transport NADH from cytosol to mitochondria.
In glycolysis, the impermeable NADH produced in the cytosol are taken up into mitochondria for oxidation via malate shuttle.
In gluconeogenesis, pyruvate in the mitochondria yields impermeable oxaloacetate, which gets translocated to the cystol via malate shuttle for the sythesis of glucose.

Harper 30th edition  Pg-125,126,173