Rad50-Mre11-Xrs2 nuclease activities on 5' flap and nicked DNA structures

CAVDAROVA, Melita. Rad50-Mre11-Xrs2 nuclease activities on 5' flap and nicked DNA structures. 2008.

Basic information

• Original name: Rad50-Mre11-Xrs2 nuclease activities on 5' flap and nicked DNA structures
• Name in Czech: Nukleázové aktivity Rad50-Mre11-Xrs2 na 5' flap a struktury DNA s jednořetězovým zlomem
• Authors: CAVDAROVA, Melita.
• Edition: 2008.

Other information

• Original language: English
• Type of outcome: Audiovisual works
• Field of Study: 10600 1.6 Biological sciences
• Country of publisher: Germany
• Confidentiality degree: is not subject to a state or trade secret
• WWW: URL
• Organization unit: Faculty of Science
• Keywords in English: Dna repair; homologous recombination; nuclease
• Tags: DNA repair, HOMOLOGOUS RECOMBINATION, nuclease
• Tags: International impact

Abstract

DNA double-strand breaks (DSBs) are among the most cytotoxic form of DNA damage and can lead to chromosomal aberrations, disruption of genomic integrity and cancer in mammals. This DNA breaks can arise from many sources, including toxic agents, ionizing radiation and enzymatic activities. Predominant cause of DSBs in proliferating cells is errors in DNA replication. Thus cells have evolved various DNA repair pathways that can remove lesions from DNA, but the two major DSB repair pathways are homologous recombination (HR) and non-homologous end joining (NHEJ). Saccharomyces cerevisiae Rad50, Mre11, and Xrs2 proteins are involved in homologous recombination, non-homologous end-joining, DNA damage checkpoint signalling, telomere maintenance and resistance to DNA-damaging agents. These proteins form a stable complex RMX mediated by simultaneous interactions of Mre11 with Rad50 and Xrs2 that has nuclease, DNA binding, and DNA end recognition activities. Mre11 plays a central role in complex assembly by binding Rad50 and Xrs2. Towards defining the biochemical functions of Mre11 and its complexes RMX and RM we have over expressed them in yeast cells and purified to near homogeneity. Furthermore, we tested enzymatic activities (endo and exonuclease) of Mre 11 on different DNA substrates and how those activities were affected by presence of RAD 50 and XRS2. At the moment we are working on expression and purification of Mre11-Xrs2 complex and nuclease deficient mutant Mre11-3.

Abstract (in Czech)

in czech