The reactions that are catalyzed by different enzymes than in glycolysis.
Glucose-6-Phosphate to Glucose
Fructo-1,6-Bisphosphate to Fructose-6-Phosphate, and
Pyruvate into Phosphoenolpyruvate
Because of glycolysis - there is not much NAD+ in the cytosol, therefore the answer is:
The ratio of NADH:NAD+ is greater in mitochondria than in the cytosol, and
Malate carries reducing potential from the mitochondria to the cytosol, thus powering cytosolic reactions that requires NADH.
The reaction pair (Oxaloacetate to Malate in mitochondria and Malate to Oxaloacetate in cytosol essentially exchange a NAD+ in the cytosol for a NADH in the mitochondria). I spent some time thought about what cytosolic reaction needs NADH, and it turns out that it is the reverse reactions. Glycolysis generates NADH from NAD+, so gluconeogenesis need NADH to generate NAD+!
Glucose-6-phosphatase is used to remove the phosphate group from glucose, therefore, its expression support gluconeogenesis.
Therefore the answer is:
Liver and kidney cells express glucose-6-phosphatase to complete gluconeogenesis.
Muscle and brain cells do not express glucose-6-phosphatase, and therefore retain glucose-6-phosphate for glycolysis.
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