DNA repair within nucleosomes

DNA lesions are repaired by a cut-and-remove process called nucleotide excision repair. An in vitro biochemically defined system has been developed in which six repair factors are sufficient to excise damage from naked DNA. In the December Molecular and Cellular Biology, Hara et al. use this system to examine the effect of DNA organization into nucleosome structures on the DNA repair process (Mol Cell Biol 2000, 20:9173-9181). A nucleosome structure was assembled by mixing human histone protein

By | December 11, 2000

DNA lesions are repaired by a cut-and-remove process called nucleotide excision repair. An in vitro biochemically defined system has been developed in which six repair factors are sufficient to excise damage from naked DNA. In the December Molecular and Cellular Biology, Hara et al. use this system to examine the effect of DNA organization into nucleosome structures on the DNA repair process (Mol Cell Biol 2000, 20:9173-9181). A nucleosome structure was assembled by mixing human histone proteins with a 136 bp DNA fragment containing a (6-4) photoproduct lesion. The nucleosome was then used as a damaged substrate using the reconstituted human excision assay or human whole-cell extracts. DNA damage within the nucleosome core was repaired at about 10% the rate of naked DNA. Hara et al. also showed that there are no additional accessibility factors that are specific for nucleotide excision repair. Hence, chromatin compaction presents a significant impediment to the human excision nuclease.

Advertisement

Popular Now

  1. NYU Halts Studies, Suspends Investigator
    The Nutshell NYU Halts Studies, Suspends Investigator

    Experiments conducted at the New York University School of Medicine violated several research standards, according to US Food and Drug Administration investigators.

  2. Exercise-Induced Muscle Factor Promotes Memory
  3. The Meaning of Pupil Dilation
    Daily News The Meaning of Pupil Dilation

    Scientists are using pupil measurements to study a wide range of psychological processes and to get a glimpse into the mind.

  4. Brexit’s Effects on Science