Baseline sister chromatid exchange in human cell lines with different levels of poly(ADP-ribose) polymerase

T. J. Jorgensen, J. C. Leonard, P. J. Thraves, A. Dritschilo

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


Poly(ADP-ribose) polymerase is a chromatin enzyme which adds long chains of ADP-ribose to various acceptor proteins in response to DNA strand breaks. Its primary function is unknown; however, a role in DNA repair and radiation resistance has been postulated based largely on experiments with enzyme inhibitors. Recent reports of mutant cell lines, deficient in poly(ADP-ribose) polymerase activity, have supported previous studies with inhibitors, which suggests the involvement of poly(ADP-ribose) polymerase in maintaining baseline levels of sister chromatid exchanges. Mutant cells with even slightly depressed enzyme levels show large elevation of baseline sister chromatid exchanges. Since intracellular poly(ADP-ribose) polymerase levels can vary greatly between different nonmutant cell lines, we surveyed levels of baseline sister chromatid exchange in normal and tumor human cell lines and compared them with endogenous levels of poly(ADP-ribose) polymerase. Despite 10-fold differences in poly(ADP-ribose) polymerase, the baseline level of sister chromatid exchanges remained relatively constant in the different cell lines (0.13 ± 0.03 SCE/chromosome), with no indication of a protective effect for cells with high levels of the enzyme.

Original languageEnglish (US)
Pages (from-to)107-110
Number of pages4
JournalRadiation research
Issue number1
StatePublished - 1991
Externally publishedYes

ASJC Scopus subject areas

  • Biophysics
  • Radiation
  • Radiology Nuclear Medicine and imaging


Dive into the research topics of 'Baseline sister chromatid exchange in human cell lines with different levels of poly(ADP-ribose) polymerase'. Together they form a unique fingerprint.

Cite this