Compartmentation of dCTP pools. Evidence from deoxyliponucleotide synthesis
1987 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 262, no 34, 16425-16432 p.Article in journal (Refereed) Published
The nucleotide fraction of cultured 3T6 and 3T3 mouse fibroblasts contains deoxy-CDP choline and deoxy-CDP ethanolamine as well as the corresponding riboliponucleotides. In permeabilized cells both deoxyliponucleotides were formed from dCTP. In intact cells they could be labeled from [5-3H] deoxycytidine or cytidine via transformation of the nucleosides to dCTP. Their turnover was slow compared to that of dCTP. When rapidly growing 3T3 cells were labeled during 90 min from deoxycytidine the specific activity of dCDP choline was 2.4 times higher than that of dCTP while after labeling from cytidine both nucleotides (and CTP) reached the same specific activity under steady state conditions. Also dCDP ethanolamine was labeled more rapidly from deoxycytidine than from cytidine. Our results suggest that the deoxyliponucleotides were synthesized from a dCTP pool that was labeled preferentially from deoxycytidine. Earlier work (Nicander, B., and Reichard, P. (1983) Proc. Natl. Acad. Sci. U. S. A. 80, 1347-1351) had demonstrated synthesis of DNA from a dCTP pool labeled preferentially from cytidine. Taken together our results suggest that deoxyliponucleotides and DNA are synthesized from separate dCTP pools.
Place, publisher, year, edition, pages
American Society for Biochemistry and Molecular Biology, 1987. Vol. 262, no 34, 16425-16432 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-98782ISI: A1987L129300026PubMedID: 3680259OAI: oai:DiVA.org:liu-98782DiVA: diva2:655846