Evidence for lipid synthesis by the dihydroxyacetone phosphate pathway in rabbit lung subcellular fractions.
Lipid synthesis by the lung requires a 3-carbon skeleton that can be provided by sn-glycerol-3-phosphate derived from glycolysis. This study investigated whether acylation of dihydroxyacetone-phosphate can serve as an alternate pathway for lung lipid synthesis. Rabbit lung microsomal and mitochondrial fractions were incubated with radiolabelled sn-glycerol-3-P and/or dihydroxyacetone-P. Palmitoyl CoA was used as acyl donor. The lipid fraction was subsequently isolated and radioactive incorporation was determined. Glycerol-3-P and dihydroxyacetone-P were both incorporated into the lipid fraction when each substrate was present alone. During incubation in the presence of equimolar concentrations of both substrates dihydroxyacetone-P accounted for 41 per cent of the total incorporation. These results show that acylation of dihydroxyacetone phosphate is a potential alternate to the glycerol-3-phosphate pathway for lung lipid synthesis.
D000818:Animals; D004099:Dihydroxyacetone Phosphate / Q000378:metabolism*; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005994:Glycerophosphates / Q000378:metabolism; D008055:Lipids / Q000096:biosynthesis*; D008168:Lung / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D008861:Microsomes / Q000201:enzymology; D008928:Mitochondria / Q000201:enzymology; D011663:Pulmonary Surfactants / Q000096:biosynthesis; D011817:Rabbits; D014306:Trioses / Q000378:metabolism*
D004791:Enzyme Inhibitors; D005994:Glycerophosphates; D008055:Lipids; D011663:Pulmonary Surfactants; D014306:Trioses; D004099:Dihydroxyacetone Phosphate