To expand the known spectrum of genes that maintain genome stability, we screened a recently released collection of temperature sensitive (Ts) yeast mutants for a chromosome instability (CIN) phenotype. Proteasome subunit genes represented a major functional group, and subsequent analysis demonstrated an evolutionarily conserved role in CIN. Analysis of individual proteasome core and lid subuni...

The histone-like protein HU is the most-abundant DNA-binding protein in bacteria. The HU protein non-specifically binds and bends DNA as a hetero- or homodimer, and can participate in DNA supercoiling and DNA condensation. It also takes part in DNA functions such as replication, recombination, and repair. HU does not recognize any specific sequences but shows a certain degree of specificity to ...

DNA double-strand break (DSB) repair by nonhomologous end joining (NHEJ) requires the assembly of several proteins on DNA ends. Although biochemical studies have elucidated several aspects of the NHEJ reaction mechanism, much less is known about NHEJ in living cells, mainly because of the inability to visualize NHEJ repair proteins at DNA damage. Here we provide evidence that a pulsed near IR l...

The use of particle ion beams in cancer radiotherapy has a long history. Today, beams of protons or heavy ions, predominantly carbon ions, can be accelerated to precisely calculated energies which can be accurately targeted to tumors. This particle therapy works by damaging the DNA of tissue cells, ultimately causing their death. Among the different types of DNA lesions, the formation of DNA do...

The nucleolus is a unique structural component of interphase nuclei where the ribosomal genes, trans-cribed by RNA polymerase I (RNA pol I), are organized. In the present study, the repair of UV-induced photolesions was investigated in the ribosomal DNA (rDNA) in relation to RNA pol I transcription. We used hamster cells because their repair phenotype permits the separate analysis of the major ...

Protein arginine methyltransferases (PRMTs) are responsible for symmetric and asymmetric methylation of arginine residues of nuclear and cytoplasmic proteins. In the nucleus, PRMTs belong to important chromatin modifying enzymes of immense functional significance that affect gene expression, splicing and DNA repair. By time-lapse microscopy we have studied the sub-cellular localization and kine...

In Deinococcus radiodurans, the extreme resistance to DNA-shattering treatments such as ionizing radiation or desiccation is correlated with its ability to reconstruct a functional genome from hundreds of chromosomal fragments. The rapid reconstitution of an intact genome is thought to occur through an extended synthesis-dependent strand annealing process (ESDSA) followed by DNA recombination. ...

A key modality of non-surgical cancer management is DNA damaging therapy that causes DNA double-strand breaks that are preferentially toxic to rapidly dividing cancer cells. Double-strand break repair capacity is recognized as an important mechanism in drug resistance and is therefore a potential target for adjuvant chemotherapy. Additionally, spontaneous and environmentally induced DSBs are kn...

Background: Nickel is a carcinogenic, heavy metal released through industrial activities and via natural resources. It is able to cause DNA damages by reducing the efficiency of DNA repair mechanisms. However, the exact time point at which it is able to interfere with these mechanisms is not yet clearly understood. Methods: To find the most nickel-vulnerable time of repair mechanisms, human de...

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 ...