DNA repair in a yeast origin of replication: contributions of photolyase and nucleotide excision repair

• Published in: Nucleic acids research Vol. 28; no. 10; pp. 2060 - 2068
• Main Authors: Suter, B, Wellinger, R.E, Thoma, F
• Format: Journal Article
• Language: English
• Published: England Oxford Publishing Limited (England) 15-05-2000; Oxford University Press
• Subjects: Abf1 protein; ars 1 region; autonomously replicating sequence; chromatin; cyclobutane pyrimidine dimers; Deoxyribodipyrimidine Photo-Lyase - metabolism; DNA Damage; DNA photolyase; DNA Repair; DNA, Fungal - genetics; DNA, Fungal - radiation effects; enzymes; Kinetics; microchromosomes; minichromosomes; Pyrimidine Dimers - metabolism; pyrimidines; Replication Origin; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - radiation effects; ultraviolet radiation; Ultraviolet Rays
• ISSN: 0305-1048; 1362-4962; 1362-4962
• DOI: 10.1093/nar/28.10.2060

DNA damage formation and repair are tightly linked to protein-DNA interactions in chromatin. We have used minichromosomes in yeast as chromatin substrates in vivo to investigate how nucleotide excision repair (NER) and repair by DNA-photolyase (photoreactivation) remove pyrimidine dimers from an origin of replication ( ARS1 ). The ARS1 region is nuclease sensitive and flanked by nucleosomes on both sides. Photoreactivation was generally faster than NER at all sites. Site-specific heterogeneity of repair was observed for both pathways. This heterogeneity was different for NER and photoreactivation and it was altered in a minichromosome where ARS1 was transcribed. The results indicate distinct inter-actions of the repair systems with protein complexes bound in the ARS region (ORC, Abf1) and a predominant role of photolyase in CPD repair of an origin of replication.