Localization of CCTbeta in rat brain and overexpression in insect cells.
OBJECTIVE
To study the localization of CTP: phosphocholine cytidylyltransferase beta isoform (CCTbeta) in rat brain, its expression in insect cells and enzymatic properties.


METHODS
Using digoxigenin-labeled CCTbeta probes, in situ hybridization was carried out in rat brain wax sections. CCTbeta was overexpressed in Trichoplusia Ni (Tn) cells using baculovirus expression system. CTP:phosphocholine cytidylyltransferase assay (CT assay) and [3H] metabolic labeling experiment were used to study its activity, properties, and the effect on phosphatidylcholine (PC) synthesis.


RESULTS
(1) CCbeta was abundant in CA1, CA2, CA4, and dentate gyrus (DG) region of hippocampus. (2) The content of CCTbeta in transfected Tn cells was over 1  104 times of that in rat brain, and CCTbeta increased the PC synthesis of Tn cells. (3) Hexadecylphosphocholine as well as some ions like Zn2+ and PO3-4 could inhibit the activity of CCTbeta, dCTP was another adaptive substrate of CCTbeta besides CTP.


CONCLUSIONS
CCTbeta showed a similar localization in rat brain with the memory enhancing peptide argipressin (4-8).
Xu
Kan-Yan
KY
Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
Xiong
Ying
Y
Xie
Zhi-Qin
ZQ
Bian
Wei
W
Jing
Nai-He
NH
Du
Yu-Cang
YC
D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism; D016367:Baculoviridae / Q000235:genetics / Q000378:metabolism; D001921:Brain / Q000201:enzymology; D019916:Choline-Phosphate Cytidylyltransferase / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D006624:Hippocampus / Q000201:enzymology*; D017403:In Situ Hybridization; D007527:Isoenzymes; D009036:Moths / Q000235:genetics / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D007527:Isoenzymes; D010446:Peptide Fragments; D001127:Arginine Vasopressin; C072508:argipressin (4-8); D019916:Choline-Phosphate Cytidylyltransferase