Repair rate maps of cyclopyrimidine dimers along the human PFG-1 gene

Journal Article · Sat Dec 31 04:00:00 EST 1994 · Environmental and Molecular Mutagenesis

OSTI ID:88811

Gao, S; Drouin, R; Holmquist, G P ^[1]

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1. Beckman Research Institute of the City of Hope Medical Center, Duarte, CA (United States)

Repair rates were measured at nucleotide resolution. Human fibroblasts were irradiated with 20 J/m{sup 2}254 nm light, allowed to repair, and the DNA was cleaved at cyclobutane pyrimidine dimers with T4 endonuclease V. The resulting breaks along the PGK-1 promoter and exon 1 were mapped by ligation-mediated polymerase chain reaction. The non-transcribed strand showed no repair rate patterns but position specific repair rates, time to 50% repair, varied greatly, between one and 15 hours. Rapid repair of the transcribed strand began almost immediately downstream of the transcription initiation site but did not attain its full effect, {le}2 hr to 50% completion, until position +140. The promoter contained two very slowly repaired regions that coincide with two transcription factor binding sites but only along the {open_quotes}transcribed strand{close_quotes}. This novel effect, strand specific repair of non-transcribed DNA, renders existing nomenclature confusing.

• OSTI ID: 88811
• Report Number(s): CONF-9405324--
• Journal Information: Environmental and Molecular Mutagenesis, Journal Name: Environmental and Molecular Mutagenesis Journal Issue: Suppl.23 Vol. 23; ISSN 0893-6692; ISSN EMMUEG
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
DNA REPAIR
FIBROBLASTS
MAN
PYRIMIDINE DIMERS
TIME DELAY