Dihydroxyacetone phosphate (DHAP) is converted to glycerol-3-phosphate (G3P) by glycerol-3-phosphate dehydrogenase (GPD1) or by glycerol-3-phosphate dehydrogenase-like (GPD1L) enzymes (Ou et al. 2006, Valdivia et al. 2009). The active forms of both enzymes are homodimers. This reaction may be found in white adipose tissues where glycerol-3-kinase activity is not observed in sufficient levels. GPD1/GPD1L reduces dihydroxyacetone phosphate with NADH donating electrons to this reduction.
glycerol-3-phosphate dehydrogenase [NAD+] activity of GPD1/GPD1L homodimer [cytosol]