{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T20:37:41Z","timestamp":1787603861738,"version":"build-2736575974"},"reference-count":30,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2020,12,29]],"date-time":"2020-12-29T00:00:00Z","timestamp":1609200000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["20H04334"],"award-info":[{"award-number":["20H04334"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["15H02817"],"award-info":[{"award-number":["15H02817"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,3,10]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>The biological effects of ionizing radiation, especially those of sparsely ionizing radiations like X-ray and \u03b3-ray, are generally reduced as the dose rate is reduced. This phenomenon is known as \u2018the dose-rate effect\u2019. The dose-rate effect is considered to be due to the repair of DNA damage during irradiation but the precise mechanisms for the dose-rate effect remain to be clarified. Ku70, Ku86 and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) are thought to comprise the sensor for DNA double-strand break (DSB) repair through non-homologous end joining (NHEJ). In this study, we measured the clonogenic ability of Ku70-, Ku86- or DNA-PKcs-deficient rodent cells, in parallel with respective control cells, in response to high dose-rate (HDR) and low dose-rate (LDR) \u03b3-ray radiation (~0.9 and ~1\u00a0mGy\/min, respectively). Control cells and murine embryonic fibroblasts (MEF) from a severe combined immunodeficiency (scid) mouse, which is DNA-PKcs-deficient, showed higher cell survival after LDR irradiation than after HDR irradiation at the same dose. On the other hand, MEF from Ku70\u2212\/\u2212 mice exhibited lower clonogenic cell survival after LDR irradiation than after HDR irradiation. XR-V15B and xrs-5 cells, which are Ku86-deficient, exhibited mostly identical clonogenic cell survival after LDR and HDR irradiation. Thus, the dose-rate effect in terms of clonogenic cell survival is diminished or even inversed in Ku-deficient rodent cells. These observations indicate the involvement of Ku in the dose-rate effect.<\/jats:p>","DOI":"10.1093\/jrr\/rraa128","type":"journal-article","created":{"date-parts":[[2020,12,10]],"date-time":"2020-12-10T15:51:08Z","timestamp":1607615468000},"page":"198-205","source":"Crossref","is-referenced-by-count":8,"title":["Diminished or inversed dose-rate effect on clonogenic ability in Ku-deficient rodent cells"],"prefix":"10.1093","volume":"62","author":[{"given":"Hisayo","family":"Tsuchiya","sequence":"first","affiliation":[{"name":"Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mikio","family":"Shimada","sequence":"additional","affiliation":[{"name":"Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaima","family":"Tsukada","sequence":"additional","affiliation":[{"name":"Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qingmei","family":"Meng","sequence":"additional","affiliation":[{"name":"Department of Interdisciplinary Environment, Graduate School of Human and Environmental Sciences, Kyoto University, Yoshidanihonmatsucho, Sakyo-ku, Kyoto 606-8501 Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junya","family":"Kobayashi","sequence":"additional","affiliation":[{"name":"Radiation Biology Center, Graduate School of Biostudies, Kyoto University, Yoshida-Konoecho, Sakyo-ku, Kyoto 606-8501 Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshihisa","family":"Matsumoto","sequence":"additional","affiliation":[{"name":"Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2020,12,29]]},"reference":[{"key":"2021032416080191500_ref1","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1177\/0146645316629336","article-title":"Dose-rate effects in radiation biology and radiation protection","volume":"45","author":"R\u00fchm","year":"2016","journal-title":"Ann ICRP"},{"key":"2021032416080191500_ref2","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1007\/s00411-015-0613-6","article-title":"Dose and dose-rate effects of ionizing radiation: A discussion in the light of radiological 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