DNA end-joining catalyzed by human cell-free extracts.
نویسندگان
چکیده
Mammalian cells defective in DNA end-joining are highly sensitive to ionizing radiation and are immunodeficient because of a failure to complete V(D)J recombination. By using cell-free extracts prepared from human lymphoblastoid cell lines, an in vitro system for end-joining has been developed. Intermolecular ligation was found to be accurate and to depend on DNA ligase IV/Xrcc4 and requires Ku70, Ku86, and DNA-PKcs, the three subunits of the DNA-activated protein kinase DNA-PK. Because these activities are involved in the cellular resistance to x-irradiation and V(D)J recombination, the development of this in vitro system provides an important advance in the study of the mechanism of DNA end-joining in human cells.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 95 24 شماره
صفحات -
تاریخ انتشار 1998