TY - JOUR
T1 - Unraveling low-level gamma radiation-responsive changes in expression of early and late genes in leaves of rice seedlings at litate Village, Fukushima
AU - Hayashi, Gohei
AU - Shibato, Junko
AU - Imanaka, Tetsuji
AU - Cho, Kyoungwon
AU - Kubo, Akihiro
AU - Kikuchi, Shoshi
AU - Satoh, Kouji
AU - Kimura, Shinzo
AU - Ozawa, Shoji
AU - Fukutani, Satoshi
AU - Endo, Satoru
AU - Ichikawa, Katsuki
AU - Agrawal, Ganesh Kumar
AU - Shioda, Seiji
AU - Fukumoto, Manabu
AU - Rakwal, Randeep
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 2014
Y1 - 2014
N2 - In the summer of 2012, 1 year after the nuclear accident in March 2011 at the Fukushima Daiichi nuclear power plant, we examined the effects of gamma radiation on rice at a highly contaminated field of Iitate village in Fukushima, Japan. We investigated the morphological and molecular changes on healthy rice seedlings exposed to continuous low-dose gamma radiation up to 4 μSv h -1, about 80 times higher than natural background level. After exposure to gamma rays, expression profiles of selected genes involved in DNA replication/repair, oxidative stress, photosynthesis, and defense/stress functions were examined by RT-PCR, which revealed their differential expression in leaves in a time-dependent manner over 3 days (6, 12, 24, 48, and 72 h). For example, OsPCNA mRNA rapidly increased at 6, 12, and 24 h, suggesting that rice cells responded to radiation stress by activating a gene involved in DNA repair mechanisms. At 72 h, genes related to the phenylpropanoid pathway (OsPAL2) and cell death (OsPR1oa) were strongly induced, indicating activation of defense/stress responses. We next profiled the transcriptome using a customized rice whole-genome 4 × 44K DNA microarray at early (6 h) and late (72 h) time periods. Low-level gamma radiation differentially regulated rice leaf gene expression (induced 4481 and suppressed 3740 at 6 h and induced 2291 and suppressed 1474 genes at 72 h) by at least 2-fold. Using the highly upregulated and downregulated gene list, MapMan bioinformatics tool generated diagrams of early and late pathways operating in cells responding to gamma ray exposure. An inventory of a large number of gamma radiation-responsive genes provides new information on novel regulatory processes in rice.
AB - In the summer of 2012, 1 year after the nuclear accident in March 2011 at the Fukushima Daiichi nuclear power plant, we examined the effects of gamma radiation on rice at a highly contaminated field of Iitate village in Fukushima, Japan. We investigated the morphological and molecular changes on healthy rice seedlings exposed to continuous low-dose gamma radiation up to 4 μSv h -1, about 80 times higher than natural background level. After exposure to gamma rays, expression profiles of selected genes involved in DNA replication/repair, oxidative stress, photosynthesis, and defense/stress functions were examined by RT-PCR, which revealed their differential expression in leaves in a time-dependent manner over 3 days (6, 12, 24, 48, and 72 h). For example, OsPCNA mRNA rapidly increased at 6, 12, and 24 h, suggesting that rice cells responded to radiation stress by activating a gene involved in DNA repair mechanisms. At 72 h, genes related to the phenylpropanoid pathway (OsPAL2) and cell death (OsPR1oa) were strongly induced, indicating activation of defense/stress responses. We next profiled the transcriptome using a customized rice whole-genome 4 × 44K DNA microarray at early (6 h) and late (72 h) time periods. Low-level gamma radiation differentially regulated rice leaf gene expression (induced 4481 and suppressed 3740 at 6 h and induced 2291 and suppressed 1474 genes at 72 h) by at least 2-fold. Using the highly upregulated and downregulated gene list, MapMan bioinformatics tool generated diagrams of early and late pathways operating in cells responding to gamma ray exposure. An inventory of a large number of gamma radiation-responsive genes provides new information on novel regulatory processes in rice.
KW - DNA repair
KW - Gamma radiation
KW - Oryza sativa
KW - OsPCNA
KW - Seedling leaf
KW - Stress response
UR - http://www.scopus.com/inward/record.url?scp=84906812279&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84906812279&partnerID=8YFLogxK
U2 - 10.1093/jhered/esu025
DO - 10.1093/jhered/esu025
M3 - Article
C2 - 25124817
AN - SCOPUS:84906812279
VL - 105
SP - 723
EP - 738
JO - Journal of Heredity
JF - Journal of Heredity
SN - 0022-1503
IS - 5
ER -