PMID- 10191259
OWN - NLM
STAT- MEDLINE
DCOM- 19990623
LR  - 20181113
IS  - 0264-6021 (Print)
IS  - 0264-6021 (Linking)
VI  - 339 ( Pt 2)
DP  - 1999 Apr 15
TI  - Cloning and expression of a human choline/ethanolaminephosphotransferase:
      synthesis of phosphatidylcholine and phosphatidylethanolamine.
PG  - 291-8
AB  - Cholinephosphotransferase catalyses the final step in the synthesis of
      phosphatidylcholine (PtdCho) via the Kennedy pathway by the transfer of
      phosphocholine from CDP-choline to diacylglycerol. Ethanolaminephosphotransferase
      catalyses an analogous reaction with CDP-ethanolamine as the phosphobase donor
      for the synthesis of phosphatidylethanolamine (PtdEtn). Together these two enzyme
      activities determine both the site of synthesis and the fatty acyl composition of
      PtdCho and PtdEtn synthesized de novo. A human
      choline/ethanolaminephosphotransferase cDNA (hCEPT1) was cloned, expressed and
      characterized. Northern blot analysis revealed one hCEPT1 2.3 kb transcript that 
      was ubiquitous and not enriched, with respect to actin, in any particular cell
      type. The open reading frame predicts a protein (hCEPT1p) of 416 amino acid
      residues with a molecular mass of 46550 Da containing seven membrane-spanning
      domains. A predicted amphipathic helix resides within the active site of the
      enzyme with the final two aspartic residues of the CDP-alcohol phosphotransferase
      motif, DG(X)2AR(X)8G(X)3D(X)3D, positioned within this helix. hCEPT1p was
      successfully expressed in a full-length, active form in Saccharomyces cerevisiae 
      cells devoid of endogenous cholinephosphotransferase or
      ethanolaminephosphotransferase activities (HJ091, cpt1::LEU2 ept1-). In vitro,
      hCEPT1p displayed broad substrate specificity, utilizing both CDP-choline and
      CDP-ethanolamine as phosphobase donors to a broad range of diacylglycerols,
      resulting in the synthesis of both PtdCho and PtdEtn. In vivo, S. cerevisiae
      cells (HJ091, cpt1::LEU2 ept1-) expressing hCEPT1 efficiently incorporated both
      radiolabelled choline and ethanolamine into phospholipids, demonstrating that
      hCEPT1p has the ability to synthesize both choline- and ethanolamine- containing 
      phospholipids in vitro and in vivo.
FAU - Henneberry, A L
AU  - Henneberry AL
AD  - Atlantic Research Centre, Departments of Pediatrics and Biochemistry, Dalhousie
      University, Halifax, Nova Scotia, Canada B3H 4H7.
FAU - McMaster, C R
AU  - McMaster CR
LA  - eng
SI  - GENBANK/AF068302
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Biochem J
JT  - The Biochemical journal
JID - 2984726R
RN  - 0 (DNA, Complementary)
RN  - 0 (Phosphatidylcholines)
RN  - 0 (Phosphatidylethanolamines)
RN  - 0 (RNA, Messenger)
RN  - EC 2.7.8.- (Transferases (Other Substituted Phosphate Groups))
RN  - EC 2.7.8.- (choline-ethanolaminephosphotransferase)
SB  - IM
MH  - Amino Acid Sequence
MH  - Cloning, Molecular
MH  - DNA, Complementary
MH  - Humans
MH  - Kinetics
MH  - Molecular Sequence Data
MH  - Phosphatidylcholines/*biosynthesis
MH  - Phosphatidylethanolamines/*biosynthesis
MH  - Protein Structure, Secondary
MH  - RNA, Messenger/genetics/metabolism
MH  - Saccharomyces cerevisiae/genetics
MH  - Sequence Homology, Amino Acid
MH  - Transferases (Other Substituted Phosphate Groups)/chemistry/*genetics
PMC - PMC1220157
EDAT- 1999/04/07 00:00
MHDA- 1999/04/07 00:01
CRDT- 1999/04/07 00:00
PHST- 1999/04/07 00:00 [pubmed]
PHST- 1999/04/07 00:01 [medline]
PHST- 1999/04/07 00:00 [entrez]
PST - ppublish
SO  - Biochem J. 1999 Apr 15;339 ( Pt 2):291-8.