| First Author | He DM | Year | 1996 |
| Journal | Mutat Res | Volume | 363 |
| Issue | 1 | Pages | 43-56 |
| PubMed ID | 8632777 | Mgi Jnum | J:32919 |
| Mgi Id | MGI:80406 | Doi | 10.1016/0921-8777(95)00060-7 |
| Citation | He DM, et al. (1996) Restoration of X-ray and etoposide resistance, Ku-end binding activity and V(D) J recombination to the Chinese hamster sxi-3 mutant by a hamster Ku86 cDNA. Mutat Res 363(1):43-56 |
| abstractText | Ku is a heterodimeric protein composed of 86 and 70 kDa subunits that binds preferentially to the double-stranded ends of DNA. Recent molecular characterization of ionizing-radiation sensitive (IRs) mutants belonging to the XRCC5 complementation group demonstrated the involvement of Ku in DNA double-strand break (DSB) repair and lymphoid V(D)J recombination. Here, we describe the isolation of a full-length hamster cDNA encoding the large subunit of the Ku heterodimer and demonstrate that the stable expression of this cDNA can functionally restore IR, Ku DNA end-binding activity and V(D)J recombination proficiency in the Chinese hamster IRs sxi-3 mutant. Moreover, we also demonstrate that sxi-3 cells are hypersensitive to etoposide, a DNA topoisomerase II inhibitor, and that resistance to this drug was restored by the Ku86 cDNA. These experiments suggest that a defect in the large subunit of the heterodimeric Ku protein is the sole factor responsible for the known defects of sxi-3 cells and our data of further support the role of Ku in DNA DSB repair and V(D)J recombination. |
