Dynamic Processing of a Common Oxidative DNA Lesion by the First Two Enzymes of the Base Excision Repair Pathway. Issue 5 (5th March 2021)

• Record Type: Journal Article
• Authors: Raper, Austin T.; Maxwell, Brian A.; Suo, Zucai
• Is Part Of: Journal of molecular biology. Volume 433:Issue 5(2021)
• Publication Date: 2021-03-05
• Subjects: Base excision repair -- Stopped-flow -- Single-molecule Förster resonance energy transfer -- Human 8-oxoguanine glycosylase -- Human AP endonuclease; AP site apurinic or apyrimidinic/abasic site -- BER Base excision repair -- 8-oxoG 8-oxo-7, 8-dihydro-2ʹ-deoxoguanine -- smFRET single-molecule Förster resonance energy transfer -- hOGG1 human 8-oxoguanine glycosylase 1 -- APE1 AP endonuclease 1 -- WT wild-type; Molecular biology -- Periodicals; Biology -- Periodicals; Biochemistry -- Periodicals; Bacteriology -- Periodicals; Molecular Biology -- Periodicals; Biochemistry -- Periodicals; Biologie moléculaire -- Périodiques; Biologie -- Périodiques; Biochimie -- Périodiques; Moleculaire biologie; Biochemistry; Biology; Molecular biology; Periodicals; 572.805
• DOI: 10.1016/j.jmb.2021.166811
• Languages: English
• ISSNs: 0022-2836

Abstract

Graphical abstract: Highlights: DNA binding and damage processing by hOGG1 involves multiple conformational modes. APE1 binds to DNA primarily with a single-state mode and rapidly cleaves abasic sites. hOGG1, the damaged DNA substrate, and APE1 form a ternary complex. APE1 actively displaces hOGG1 from its abasic site product during BER. Abstract: Base excision repair (BER) is the primary pathway by which eukaryotic cells resolve single base damage. One common example of single base damage is 8-oxo-7, 8-dihydro-2ʹ-deoxoguanine (8-oxoG). High incidence and mutagenic potential of 8-oxoG necessitate rapid and efficient DNA repair. How BER enzymes coordinate their activities to resolve 8-oxoG damage while limiting cytotoxic BER intermediates from propagating genomic instability remains unclear. Here we use single-molecule Förster resonance energy transfer (smFRET) and ensemble-level techniques to characterize the activities and interactions of consecutive BER enzymes important for repair of 8-oxoG. In addition to characterizing the damage searching and processing mechanisms of human 8-oxoguanine glycosylase 1 (hOGG1), our data support the existence of a ternary complex between hOGG1, the damaged DNA substrate, and human AP endonuclease 1 (APE1). Our results indicate that hOGG1 is actively displaced from its abasic site containing product by protein–protein interactions with APE1 to ensure timely repair of damaged DNA.