PMID: 9621Aug 1, 1976

Properties of DNA ligase from uninfected and virus-infected HeLa cells

Nucleic Acids Research
S Spadari


HeLa cells contain a high M.W. form of DNA ligase which can be completely converted to a low M.W. form. Stokes radius, frictional ratio, sedimentation coefficient, molecular weight, pH dependence, and heat inactivation rate of the two forms have been studied. The major properties of the two forms of DNA ligase in HeLa cells (in particular molecular weights and pH dependence) resemble those of the "dimer" and "monomer" structures described in cultured human cells (Pedrali, G., Spadari, S., Ciarrocchi, G., Pedrini, M., Falaschi, A. (1973) Eur. J. Biochem., 39 343) . In synchronized HeLa cells, the DNA ligase shows a two fold increase during S phase and parallels the increase in the DNA synthesis rate. DNA ligase increases in parallel with viral DNA synthesis after infection of HeLa cells with vaccinia and Herpes virus but its cofactor requirements and physical properties (including the dimer leads to monomer conversion) are unchanged, suggesting that the newly formed ligase is not virus-coded.


Feb 1, 1975·Proceedings of the National Academy of Sciences of the United States of America·S Spadari, A Weissbach
Mar 1, 1976·Proceedings of the National Academy of Sciences of the United States of America·U BertazzoniS Spadari
Nov 15, 1973·European Journal of Biochemistry·G C Pedrali NoyA Falaschi
Dec 22, 1972·Biochimica Et Biophysica Acta·U BertazzoniF Campagnari
Mar 1, 1973·Archives of Biochemistry and Biophysics·P BöhlenS Udenfriend
Feb 15, 1973·Journal of Molecular Biology·L M ChangF J Bollum
Aug 6, 1973·Biochemical and Biophysical Research Communications·S Söderhäll, T Lindahl
Sep 13, 1971·European Journal of Biochemistry·S SpadariA Falaschi
Sep 1, 1969·The Journal of Cell Biology·D M BerkowitzM Sporn


Jan 1, 1979·Pharmacology & Therapeutics. Part B: General & Systematic Pharmacology·S Kit
Sep 1, 1990·Mutation Research·D D LaskoT Lindahl
Nov 25, 1989·Nucleic Acids Research·S M Kerr, G L Smith
Nov 1, 1978·Nucleic Acids Research·M Mezzina, S Nocentini
Jan 15, 1987·European Journal of Biochemistry·M MezzinaA Sarasin
Dec 1, 1977·Virology·M EstebanJ A Holowczak

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