Determination of human DNA polymerase utilization for the repair of a model ionizing radiation-induced DNA strand break lesion in a defined vector substrate

Thomas A. Winters, Pamela S. Russell, Manu Kohli, Mubasher E. Dar, Ronald D. Neumann, Timothy J. Jorgensen

Research output: Contribution to journalArticle

Abstract

Human DNA polymerase and DNA ligase utilization for the repair of a major class of ionizing radiation-induced DNA lesion [DNA single-strand breaks containing 3'-phosphoglycolate (3'-PG)] was examined using a novel, chemically defined vector substrate containing a single, site-specific 3'-PG single-strand break lesion. In addition, the major human AP endonuclease, HAP1 (also known as APE1, APEX, Ref-1), was tested to determine if it was involved in initiating repair of 3'-PG-containing single-strand break lesions. DNA polymerase β was found to be the primary polymerase responsible for nucleotide incorporation at the lesion site following excision of the 3'-PG blocking group. However, DNA polymerase δ/ε was also capable of nucleotide incorporation at the lesion site following 3'-PG excision. In addition, repair reactions catalyzed by DNA polymerase β were found to be most effective in the presence of DNA ligase III, while those catalyzed by DNA polymerase δ/ε appeared to be more effective in the presence of DNA ligase I. Also, it was demonstrated that the repair initiating 3'-PG excision reaction was not dependent upon HAP1 activity, as judged by inhibition of HAP1 with neutralizing HAP1-specific polyclonal antibody.

Original languageEnglish (US)
Pages (from-to)2423-2433
Number of pages11
JournalNucleic acids research
Volume27
Issue number11
DOIs
StatePublished - Jun 1 1999

ASJC Scopus subject areas

  • Genetics

Fingerprint Dive into the research topics of 'Determination of human DNA polymerase utilization for the repair of a model ionizing radiation-induced DNA strand break lesion in a defined vector substrate'. Together they form a unique fingerprint.

  • Cite this