K.A. Richardson et al. / Biochemical Pharmacology 68 (2004) 2337–2346
2345
(dFdCTP) or strong (araCTP) chain termination when pol
Acknowledgement
a elongates exogenously added primentemplates. These
data are consistent with previous studies showing that calf
thymus pol a-primase readily incorporates araATP into
internucleotide linkages during the elongation of primase
synthesized primers but not when elongating exogenously
added primer:templates.
This work was partially supported by National Institutes
of Health Grant GM54194 to R.D.K. T.P.V. was supported
in part by a NIH Predoctoral Training Grant T32
GM08759.
In comparison, T-araC still appeared to cause a signifi-
cant reduction in the elongation by the primase-coupled
pol a complex. Despite this reduction in elongation,
studies in cells and tumors demonstrate that the vast
majority of T-araC present in DNA following treatment
is also located in intranucleotide linkages [31].
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A key question is how large amounts of T-araCTP
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