PMID- 10480912
OWN - NLM
STAT- MEDLINE
DCOM- 19991013
LR  - 20190508
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 274
IP  - 38
DP  - 1999 Sep 17
TI  - Distribution of CTP:phosphocholine cytidylyltransferase (CCT) isoforms.
      Identification of a new CCTbeta splice variant.
PG  - 26992-7001
AB  - CTP:phosphocholine cytidylyltransferase is a major regulator of
      phosphatidylcholine biosynthesis. A single isoform, CCTalpha, has been studied
      extensively and a second isoform, CCTbeta, was recently identified. We identify
      and characterize a third cDNA, CCTbeta2, that differs from CCTbeta1 at the
      carboxyl-terminal end and is predicted to arise as a splice variant of the
      CCTbeta gene. Like CCTalpha, CCTbeta2 is heavily phosphorylated in vivo, in
      contrast to CCTbeta1. CCTbeta1 and CCTbeta2 mRNAs were differentially expressed
      by the human tissues examined, whereas CCTalpha was more uniformly represented.
      Using isoform-specific antibodies, both CCTbeta1 and CCTbeta2 localized to the
      endoplasmic reticulum of cells, in contrast to CCTalpha which resided in the
      nucleus in addition to associating with the endoplasmic reticulum. CCTbeta2
      protein has enzymatic activity in vitro and was able to complement the
      temperature-sensitive cytidylyltransferase defect in CHO58 cells, just as
      CCTalpha and CCTbeta1 supporting proliferation at the nonpermissive conditions.
      Overexpression experiments did not reveal discrete physiological functions for
      the three isoforms that catalyze the same biochemical reaction; however, the
      differential cellular localization and tissue-specific distribution suggest that 
      CCTbeta1 and CCTbeta2 may play a role that is distinct from ubiquitously
      expressed CCTalpha.
FAU - Lykidis, A
AU  - Lykidis A
AD  - Department of Biochemistry, St. Jude Children's Research Hospital, Memphis,
      Tennessee 38105, USA.
FAU - Baburina, I
AU  - Baburina I
FAU - Jackowski, S
AU  - Jackowski S
LA  - eng
GR  - CA 21765/CA/NCI NIH HHS/United States
GR  - GM45737/GM/NIGMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (DNA, Complementary)
RN  - 0 (Isoenzymes)
RN  - EC 2.7.7.15 (Choline-Phosphate Cytidylyltransferase)
SB  - IM
MH  - Alternative Splicing
MH  - Amino Acid Sequence
MH  - Animals
MH  - Base Sequence
MH  - COS Cells
MH  - Choline-Phosphate Cytidylyltransferase/*genetics/*isolation & purification
MH  - DNA, Complementary/chemistry
MH  - HeLa Cells
MH  - Humans
MH  - Isoenzymes/*genetics/*isolation & purification
MH  - Molecular Sequence Data
MH  - Phosphorylation
MH  - Polymerase Chain Reaction
EDAT- 1999/09/10 00:00
MHDA- 1999/09/10 00:01
CRDT- 1999/09/10 00:00
PHST- 1999/09/10 00:00 [pubmed]
PHST- 1999/09/10 00:01 [medline]
PHST- 1999/09/10 00:00 [entrez]
AID - 10.1074/jbc.274.38.26992 [doi]
PST - ppublish
SO  - J Biol Chem. 1999 Sep 17;274(38):26992-7001. doi: 10.1074/jbc.274.38.26992.