Differential contributions of choline phosphotransferases CPT1 and CEPT1 to the biosynthesis of choline phospholipids
| Autor: | Hiroyuki Sugimoto, Yasuhiro Horibata |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
CHO-K1
Chinese hamster ovary-K1 HEK293 human embryonic kidney 293 Transferases (Other Substituted Phosphate Groups) BFA brefeldin A Biochemistry Choline Phosphotransferase chemistry.chemical_compound CPT1 choline phosphotransferase 1 PC phosphatidylcholine Endocrinology DKO double-KO plasmanyl-PC 1-alkyl-2-acyl-sn-glycerophosphocholine plasmenyl-PE 1-alkenyl-2-acyl-sn-glycerophosphoethanolamine Cells Cultured Phospholipids chemistry.chemical_classification choline phosphotransferase 1 trans-Golgi network food and beverages PL phospholipid CRISPR clustered regularly interspaced short palindromic repeats Kennedy pathway Diacylglycerol Cholinephosphotransferase lipids (amino acids peptides and proteins) choline/ethanolamine phosphotransferase 1 Research Article radiolabeling Phospholipid phospholipid metabolism QD415-436 PE phosphatidylethanolamine DAG 1 2-diacyl-sn-glycerol Biosynthesis Phosphatidylcholine Humans EPT1 ethanolamine phosphotransferase 1 phosphatidylcholine CEPT1 choline/ethanolamine phosphotransferase 1 Phosphatidylethanolamine Endoplasmic reticulum TGN trans-Golgi network Cell Biology plasmenyl-PC 1-alkenyl-2-acyl-sn-glycerophosphocholine Enzyme HEK293 Cells chemistry phospholipid biosynthesis PUFA HA hemagglutinin |
| Zdroj: | Journal of Lipid Research Journal of Lipid Research, Vol 62, Iss, Pp 100100-(2021) |
| ISSN: | 1539-7262 0022-2275 |
| Popis: | Choline phospholipids (PLs) such as phosphatidylcholine (PC) and 1-alkyl-2-acyl-sn-glycerophosphocholine are important components for cell membranes and also serve as a source of several lipid mediators. These lipids are biosynthesized in mammals in the final step of the CDP-choline pathway by the choline phosphotransferases choline phosphotransferase 1 (CPT1) and choline/ethanolamine phosphotransferase 1 (CEPT1). However, the contributions of these enzymes to the de novo biosynthesis of lipids remain unknown. Here, we established and characterized CPT1- and CEPT1-deficient human embryonic kidney 293 cells. Immunohistochemical analyses revealed that CPT1 localizes to the trans-Golgi network and CEPT1 to the endoplasmic reticulum. Enzyme assays and metabolic labeling with radiolabeled choline demonstrated that loss of CEPT1 dramatically decreases choline PL biosynthesis. Quantitative PCR and reintroduction of CPT1 and CEPT1 revealed that the specific activity of CEPT1 was much higher than that of CPT1. LC-MS/MS analysis of newly synthesized lipid molecular species from deuterium-labeled choline also showed that these enzymes have similar preference for the synthesis of PC molecular species, but that CPT1 had higher preference for 1-alkyl-2-acyl-sn-glycerophosphocholine with PUFA than did CEPT1. The endogenous level of PC was not reduced by the loss of these enzymes. However, several 1-alkyl-2-acyl-sn-glycerophosphocholine molecular species were reduced in CPT1-deficient cells and increased in CEPT1-deficient cells when cultured in 0.1% FBS medium. These results suggest that CEPT1 accounts for most choline PL biosynthesis activity, and that both enzymes are responsible for the production of different lipid molecular species in distinct organelles. |
| Databáze: | OpenAIRE |
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