Binding of Zinc Finger Protein Transcription Factor IIIA to Its Cognate DNA Sequence with Single UV Photoproducts at Specific Sites and Its Effect on DNA Repair

Young Ho Kwon, Michael J. Smerdon

Research output: Contribution to journalArticle

10 Scopus citations

Abstract

The relationship between DNA repair efficiency at specific locations in the binding site of the nine-zinc finger protein transcription factor IIIA (TFIIIA) and binding of its individual zinc fingers was studied. Homogeneously damaged oligonucleotides, which contained a single cis-syn cyclobutane thymine dimer (CTD) at one of six different sites in the internal control region (ICR) of the 5 S rRNA gene to generate a series of damaged DNA substrates, were prepared by chemical synthesis. Binding of TFIIIA to the substrates was assayed by measurement of dissociation constants (Kd), dissociation rates (koff), and protein-DNA contacts. The results indicated that a single CTD in the ICR does not significantly affect the Kd of TFIIIA. In contrast, CTDs at positions +55 and +72 (from the transcription start site) in the ICR markedly enhanced koff of TFIIIA from the complex. In addition, CTDs in these two sites increased methylation of the N7 of guanines (by dimethyl sulfate) in the zinc finger contacts of the ICR-TFIIIA complex. Furthermore CTDs at +55 and +72 were more efficiently removed from the complex than CTDs at other sites in the ICR by Xenopus oocyte nuclear extracts. This suggests that repair of CTDs closely correlates with changes in the binding of individual zinc fingers of the ICR-TFIIIA complex. These results have implications for the mechanism of DNA damage recognition and repair in protein-DNA complexes.

Original languageEnglish (US)
Pages (from-to)45451-45459
Number of pages9
JournalJournal of Biological Chemistry
Volume278
Issue number46
DOIs
StatePublished - Nov 14 2003
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Binding of Zinc Finger Protein Transcription Factor IIIA to Its Cognate DNA Sequence with Single UV Photoproducts at Specific Sites and Its Effect on DNA Repair'. Together they form a unique fingerprint.

  • Cite this