Format

Send to

Choose Destination
Nucleic Acids Res. 2011 Jan;39(2):e11. doi: 10.1093/nar/gkq1082. Epub 2010 Nov 9.

Complementary non-radioactive assays for investigation of human flap endonuclease 1 activity.

Author information

1
NIH Chemical Genomics Center, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-3370, USA.

Abstract

FEN1, a key participant in DNA replication and repair, is the major human flap endonuclease that recognizes and cleaves flap DNA structures. Deficiencies in FEN1 function or deletion of the fen1 gene have profound biological effects, including the suppression of repair of DNA damage incurred from the action of various genotoxic agents. Given the importance of FEN1 in resolving abnormal DNA structures, inhibitors of the enzyme carry a potential as enhancers of DNA-interactive anticancer drugs. To facilitate the studies of FEN1 activity and the search for novel inhibitors, we developed a pair of complementary-readout homogeneous assays utilizing fluorogenic donor/quencher and AlphaScreen chemiluminescence strategies. A previously reported FEN1 inhibitor 3-hydroxy-5-methyl-1-phenylthieno[2,3-d]pyrimidine-2,4(1H,3H)-dione displayed equal potency in the new assays, in agreement with its published IC(50). The assays were optimized to a low 4 µl volume and used to investigate a set of small molecules, leading to the identification of previously-unreported FEN1 inhibitors, among which aurintricarboxylic acid and NSC-13755 (an arylstibonic derivative) displayed submicromolar potency (average IC(50) of 0.59 and 0.93 µM, respectively). The availability of these simple complementary assays obviates the need for undesirable radiotracer-based assays and should facilitate efforts to develop novel inhibitors for this key biological target.

PMID:
21062821
PMCID:
PMC3025571
DOI:
10.1093/nar/gkq1082
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center