Abstract
In vivo radiotracer experiments using [1-14C]acetate as the precursor were conducted to investigate the biosynthesis of vernolic acid (12, 13-epoxy-cis-9-octadecenoic acid) in the seeds of Vernonia galamensis. The acetate precursor radioactively labeled vernolate in phosphatidylcholine (PC), diacylglycerol, and triacylglycerol. Time-course kinetics of the incorporation of the radioactive tracer indicated that vernolate is synthesized while the acyl moiety is esterified to PC. Pulsechase experiments provided additional supporting evidence that vernolate is synthesized while esterified to PC. These results are consistent with the hypothesis that linoleoyl PC is the precursor of vernoleoyl-PC. Subsequently, vernolate is quickly moved from the PC pool to the triacylglycerol pool, where it accumulates.
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Abbreviations
- DAF:
-
days after flowering
- DAG:
-
diacylglycerol
- PC:
-
phosphatidylcholine
- PE:
-
phosphatidylethanolamine
- PI:
-
phosphatidylinositol
- TAG:
-
triacylglycerol
- TLC:
-
thin-layer chromatography
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Liu, L., Hammond, E.G. & Nikolau, B.J. In vivo studies of the biosynthesis of vernolic acid in the seed of Vernonia galamensis . Lipids 33, 1217–1221 (1998). https://doi.org/10.1007/s11745-998-0326-3
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DOI: https://doi.org/10.1007/s11745-998-0326-3