English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Etoposides block cell division by interfering with the action of topoisomerase II, leaving enzyme-DNA double-strand breaks. We found that certain components of the trimeric DNA-dependent protein kinase influence cell survival following etoposide damage. Interestingly, either Ku70- or Ku80-deficient cell lines, but not mutant cell lines of the DNA-PK catalytic sub-unit (DNA-PKcs), were found to be hypersensitive to the effects of etoposide VP16. Ku70- and Ku80-deficient cells can be complemented to an etoposide resistant phenotype by introducing wildtype Ku70 or Ku80 cDNAs. Mutational analysis of introduced Ku70 cDNAs into murine embryonic stem cells deleted for Ku70 (-/-) showed that mutants where heterodimerization and DNA binding functions of Ku were disrupted, also blocked the restoration of etoposide resistance. In contrast with the differential etoposide sensitivity of DNA-PK mutants, both Ku- and DNA-PKcs-deficient cell lines showed G2 ionizing radiation-induced delays, a cell cycle phase where topoisomerase II function is critical. Thus, the topoisomerase II cleaved complexes may be an example of DNA lesions requiring the Ku heterodimer, but not DNA-PK for DNA repair.

Differential etoposide sensitivity of cells deficient in the Ku and DNA- PKcs components of the DNA-dependent protein kinase