Nonhomologous end-joining repair plays a more important role than homologous recombination repair in defining radiosensitivity after exposure to high-LET radiation

Takahashi, Akihisa*; Kubo, Makoto*; Ma, H.*; Nakagawa, Akiko*; Yoshida, Yukari*; Isono, Mayu*; Kanai, Tatsuaki*; Ono, Tatsuya*; Furusawa, Yoshiya*; Funayama, Tomoo; et al.

Radiation Research, 182(3), p.338 - 344, 2014/09

https://doi.org/10.1667/RR13782.1

To clarify whether high-LET radiation inhibits all repair pathways or specifically one repair pathway, studies were designed to examine the effects of radiation with different LET values on DNA DSB repair and radiosensitivity. Embryonic fibroblasts bearing repair gene KO were exposed to X rays, carbon-, iron-, neon- and argon-ion beams. Cell survival was measured with colony-forming assays. The sensitization enhancement ratio (SER) values were calculated using the 10% survival dose of wild-type cells and repair-deficient cells. Cellular radiosensitivity was listed in descending order: double-KO cells NHEJ-KO cells HR-KO cells wild-type cells. Although HR-KO cells had an almost constant SER value, NHEJ-KO cells showed a high-SER value when compared to HR-KO cells, even with increasing LET values. These results suggest that with carbon-ion therapy, targeting NHEJ repair yields higher radiosensitivity than targeting homologous recombination repair.

Double loss-of-function mutation in and genes delays flowering under continuous light but accelerates it under long days and short days; An Important role for CRY2 to accelerate flowering time in continuous light

Nefissi, R.*; Natsui, Yu*; Miyata, Kana*; Oda, Atsushi*; Hase, Yoshihiro; Nakagawa, Mayu*; Ghorbel, A.*; Mizoguchi, Tsuyoshi*

Journal of Experimental Botany, 62(8), p.2731 - 2744, 2011/02

https://doi.org/10.1093/jxb/erq450

no abstracts in English

Isolation and characterization of suppressors of the in

Natsui, Yu*; Nefissi, R.*; Miyata, Kana*; Oda, Atsushi*; Hase, Yoshihiro; Nakagawa, Mayu*; Mizoguchi, Tsuyoshi*

Plant Biotechnology, 27(5), p.463 - 468, 2010/12

https://doi.org/10.5511/plantbiotechnology.10.0722a

EARLY FLOWERING 3 (ELF3) is a circadian clock protein with a major role in maintaining circadian rhythms in plants. In this work, was mutagenized by EMS in plants of the Lansberg background to isolate suppressors of and to understand the molecular mechanisms of flowering time controlled by ELF3. Two suppressors, obtained from this screen and from a precious study, were chosen for further analysis. Genetic mapping, gene expression analysis, and sequencing identified and as new alleles of and , respectively. Genetic interactions between and and between and in the control of the floral activator were also investigated. Six suppressor of were classified at least into four subgroups based on the expression of such floral regulators as GI, CO, FT, SVP, and FLC, and on their flowering times under LL, LD, and SD. This classification scheme is useful for the characterization of unidentified suppressor mutations.

Functional analysis of the low-fidelity DNA polymerase AtREV1

Takahashi, Shinya*; Nakagawa, Mayu; Tanaka, Atsushi; Narumi, Issei; Shimizu, Kikuo*; Sakamoto, Ayako

JAEA-Review 2008-055, JAEA Takasaki Annual Report 2007, P. 58, 2008/11

https://jopss.jaea.go.jp/pdfdata/JAEA-Review-2008-055.pdf

no abstracts in English

Y-family DNA polymerase catalyses translesion synthesis and interacts functionally with PCNA2

Anderson, H.*; Vonarx, E.*; Pastushok, L.*; Nakagawa, Mayu; Katafuchi, Atsushi*; Gruz, P.*; Rubbo, A.*; Grice, D.*; Osmond, M.*; Sakamoto, Ayako; et al.

Plant Journal, 55(6), p.895 - 908, 2008/09

https://doi.org/10.1111/j.1365-313X.2008.03562.x

Natural variation of polyglutamine repeats of a circadian clock gene in

Tajima, Takeomi*; Oda, Atsushi*; Nakagawa, Mayu; Kamada, Hiroshi*; Mizoguchi, Tsuyoshi*

Plant Biotechnology, 24(2), p.237 - 240, 2007/03

https://doi.org/10.5511/plantbiotechnology.24.237

no abstracts in English

Analysis of TLS related factors in Arabidopsis

Nakagawa, Mayu; Sakamoto, Ayako; Takahashi, Shinya*; Tanaka, Atsushi; Narumi, Issei

no journal, , 

no abstracts in English

Effect of translesion synthesis deficiency on mutation frequency in Arabidopsis

Nakagawa, Mayu; Takahashi, Shinya*; Sakamoto, Ayako; Tanaka, Atsushi; Narumi, Issei

no journal, , 

no abstracts in English

Suppression of phenotypes of the clock mutant early flowering 3 (elf3) by a deletion allele of fha/cry2 mutation in Arabidopsis

Natsui, Yu*; Nefissi, R.*; Miyata, Kana*; Oda, Atsushi*; Hase, Yoshihiro; Nakagawa, Mayu; Mizoguchi, Tsuyoshi*

no journal, , 

EARLY FLOWERING 3 (ELF3) plays key roles in the control of light response, organ elongation, flowering time and circadian rhythms in Arabidopsis. ELF3 does not show significant homology to any other proteins in the public databases. Therefore biochemical function of the ELF3 has not been well understood. To understand molecular mechanisms underlying the a variety of phenotypes in the elf3 mutants, suppressors of elf3-1 were screened for, using the elf3-1 seeds mutagenized with heavy ion beams. Here we demonstrate that in one of the suppressor lines, S#20, early flowering, small cotyledon and pale green phenotypes of elf3-1 were suppressed, whereas long hypocotyl phenotype was enhanced. The recessive suppressor mutation was named suppressor of elf3 20 (sel20) and mapped to the upper side of Ch1. We have found 21-bp deletion in the FHA/CRY2 gene in the sel20. We will discuss possible roles of CRY2 in the multiple functions of ELF3.

is involved in the damage checkpoint in Arabidopsis

Sakamoto, Ayako; Nakagawa, Mayu; Sato, Katsuya; Narumi, Issei

no journal, , 

no abstracts in English