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Updated: Jul 11, 2026
09:33
In Vitro Assay to Measure Phosphatidylethanolamine Methyltransferase Activity
Published on: January 5, 2016
Does Litomosoides sigmodontis synthesize dimethylethanolamine from choline?
K M Houston1, S A Babayan, J E Allen
1Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow G4 0NR, UK.
Parasitology
|September 26, 2007
Summary
Juvenile Litomosoides sigmodontis worms modify a protein (Juv-p120) with dimethylethanolamine (DMAE). Research suggests choline, not ethanolamine, may be the precursor for this DMAE modification in these parasitic worms.
Area of Science:
- Biochemistry
- Parasitology
- Molecular Biology
Background:
- Juvenile female Litomosoides sigmodontis secrete a protein, Juv-p120, extensively modified with dimethylethanolamine (DMAE).
- The precise origin and metabolic pathway of the DMAE modification remain unclear.
Purpose of the Study:
- To investigate the source of dimethylethanolamine (DMAE) decoration on the Juv-p120 protein in Litomosoides sigmodontis.
- To elucidate the metabolic pathways involved in DMAE precursor uptake and incorporation in these parasitic worms.
Main Methods:
- Worms were incubated with radio-isotope labeled [3H]-choline and [3H]-ethanolamine.
- Analysis of radio-isotope labeled products in worm tissues and secreted proteins, including phospholipids and Juv-p120.
- Quantification of isotope incorporation into phosphatidylcholine, phosphatidylethanolamine, and Juv-p120.
Main Results:
- Both [3H]-choline and [3H]-ethanolamine were readily incorporated into worm phospholipids, specifically phosphatidylcholine and phosphatidylethanolamine, respectively.
- Worms exhibited a significantly higher uptake of labeled ethanolamine compared to choline (approximately 30-fold).
- Juv-p120 showed faint labeling with [3H]-ethanolamine but was more readily labeled with [3H]-choline, with isotope-labeled phosphatidylcholine also detected when pulsing with [3H]-ethanolamine.
Conclusions:
- The results suggest that while ethanolamine is readily taken up, choline may serve as the precursor for DMAE modification of Juv-p120 in Litomosoides sigmodontis.
- This finding presents a novel metabolic pathway where choline is converted to DMAE for protein decoration in this nematode species.
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