In recent years, our knowledge surrounding mammalian mitochondrial DNA (mtDNA) damage and repair has increased significantly. Greater insights into the factors that govern mtDNA repair are being elucidated, thus contributing to an increase in our understanding year on year. In this short review two enzymes, tyrosyl-DNA-phosphodiesterase 1 (TDP1) and aprataxin (APTX), involved in mitochondrial s...

objective(s): coronary artery disease (cad) is the leading cause of death in both male and female worldwide. the main cause of cad is the atherosclerosis of coronary arteries, which is, mostly caused by genetic alteration. 50% of such cases occur in mitotic cells where single-strand breaks occur spontaneously or due to ionizing radiation. x-ray repair cross-complementing protein 1 (xrcc1) as a ...

More than 15% of cancer deaths worldwide are associated with underlying infections or inflammatory conditions, therefore understanding how inflammation contributes to cancer etiology is important for both cancer prevention and treatment. Inflamed tissues are known to harbor elevated etheno-base (ε-base) DNA lesions induced by the lipid peroxidation that is stimulated by reactive oxygen and nitr...

DNA damage signaling and repair take place in a chromatin context. Consequently, chromatin-modifying enzymes, including adenosine triphosphate-dependent chromatin remodeling enzymes, play an important role in the management of DNA double-strand breaks (DSBs). Here, we show that the p400 ATPase is required for DNA repair by homologous recombination (HR). Indeed, although p400 is not required for...

DNA is constantly exposed to both endogenous and exogenous damages. More than 10,000 DNA modifications are induced every day in each cell's genome. Maintenance of the integrity of the genome is accomplished by several DNA repair systems. The core enzymes for these pathways are the DNA polymerases. Out of 17 DNA polymerases present in a mammalian cell, at least 13 are specifically devoted to DNA...

Nitric oxide (NO) induces deamination of guanine, yielding xanthine and oxanine (Oxa). Furthermore, Oxa reacts with polyamines and DNA binding proteins to form cross-link adducts. Thus, it is of interest how these lesions are processed by DNA repair enzymes in view of the genotoxic mechanism of NO. In the present study, we have examined the repair capacity for Oxa and Oxa-spermine cross-link ad...

The mammalian family X DNA polymerases (DNA polymerases beta, lambda, mu, and TdT) contribute to base excision repair and double-strand break repair by virtue of their ability to fill short gaps in DNA. Structural information now exists for all four of these enzymes, making this the first mammalian polymerase family whose structural portrait is complete. Here we consider how distinctive structu...

The distribution of methyl methanesulfonate induced DNA repair was measured in mouse mammary cell chromatin by digestion of "repair labeled" nuclei with micrococcal nuclease. The results indicate that there is a nonuniform distribution of DNA repair in chromatin. The chromatin fraction digested during the first 5 minutes of incubation with micrococcal nuclease appears to be a primary site of DN...

The nuclear pore complex is a multiprotein comprising approximately 30 different proteins called nucleoporins (Nups). Recent studies in yeast, animals, and plants have shown that the Nups bind to chromatin interact with transcription factors, chromatin-remodeling histone-modifying enzymes, structural proteins, including CCCTC-binding factor cohesin. These findings suggest provide subnuclear pla...