The requirement of Artemis in double-strand break repair depends on the type of DNA damage.
Artemis is a recently identified factor involved in V(D)J recombination and nonhomologous end joining (NHEJ) of DNA double-strand break (DSB) repair. Here, we performed targeted disruption of the Artemis gene (ARTEMIS) in the human pre-B cell line Nalm-6. Unexpectedly, we found that cells lacking Artemis exhibit increased sensitivity to low doses, but not high doses, of ionizing radiation. We also show that ARTEMIS-deficient cells are hypersensitive to the topoisomerase II inhibitor etoposide, but to a much lesser extent than cells lacking DNA ligase IV, a critical component of NHEJ. Unlike DNA ligase IV-deficient cells, ARTEMIS-deficient cells were not hypersensitive to ICRF-193, a topoisomerase II inhibitor that does not stabilize topoisomerase II-DNA cleavable complexes. Collectively, our results suggest that Artemis only partially participates in the NHEJ pathway to repair DSBs in human somatic cells.
Kurosawa
Aya
A
Graduate School of Integrated Science, Yokohama City University, Yokohama, Japan.
Koyama
Hideki
H
Takayama
Shinichi
S
Miki
Kensuke
K
Ayusawa
Dai
D
Fujii
Michihiko
M
Iiizumi
Susumu
S
Adachi
Noritaka
N
D015139:Blotting, Southern; D015153:Blotting, Western; D002478:Cells, Cultured / Q000187:drug effects / Q000528:radiation effects; D003114:Colony-Forming Units Assay; D053903:DNA Breaks, Double-Stranded / Q000187:drug effects* / Q000528:radiation effects*; D017931:DNA Primers / Q000737:chemistry; D004260:DNA Repair / Q000187:drug effects* / Q000528:radiation effects*; D004250:DNA Topoisomerases, Type II / Q000378:metabolism; D004268:DNA-Binding Proteins; D054659:Diketopiperazines; D004307:Dose-Response Relationship, Radiation; D004720:Endonucleases; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005047:Etoposide / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D009687:Nuclear Proteins / Q000502:physiology*; D010879:Piperazines / Q000494:pharmacology; D054448:Precursor Cells, B-Lymphoid / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011836:Radiation Tolerance; D011839:Radiation, Ionizing; D011995:Recombination, Genetic / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D059005:Topoisomerase II Inhibitors
D017931:DNA Primers; D004268:DNA-Binding Proteins; D054659:Diketopiperazines; D004791:Enzyme Inhibitors; D009687:Nuclear Proteins; D010879:Piperazines; D012333:RNA, Messenger; D059005:Topoisomerase II Inhibitors; C070899:4,4'-(1,2-dimethyl-1,2-ethanediyl)bis-2,6-piperazinedione; D005047:Etoposide; C426344:DCLRE1C protein, human; D004720:Endonucleases; D004250:DNA Topoisomerases, Type II