G3P is an intermediate in glycolysis, gluconeogenesis, pentose phosphate pathway, and the Calvin cycle.

G3P participates in the reactions below:

1. D-Fructose-1,6-Bisphosphate <=> DHAP + G3P (catalyzed by Fructose-1,6-Bisphosphate Aldolase)

2. DHAP <=> G3P (catalyzed by Triose Phosphate Isomerase)

3. G3P + NAD⁺ + Pi <=> 1,3 Bisphosphoglycerate + NADH + H⁺ (catalyzed by Glyceraldehyde-3-Phosphate Dehydrogenase)

In the pentose phosphate pathway G3P participates in the reactions below:

1. Xylulose-5-Phosphate + Ribose-5-Phosphate <=> G3P + Sedoheptulose-7-Phosphate (catalyzed by Transketolase)

2. G3P + Sedoheptulose-7-Phosphate <=> Erythrose-4-Phosphate + Fructose-6-Phosphate (catalyzed by Transaldolase)