解析福岛县饭馆村水稻幼苗叶片中早期和晚期基因表达对低水平伽马辐射的响应变化

Unraveling low-level gamma radiation--responsive changes in expression of early and late genes in leaves of rice seedlings at Iitate Village, Fukushima.

作者信息

Hayashi Gohei, Shibato Junko, Imanaka Tetsuji, Cho Kyoungwon, Kubo Akihiro, Kikuchi Shoshi, Satoh Kouji, Kimura Shinzo, Ozawa Shoji, Fukutani Satoshi, Endo Satoru, Ichikawa Katsuki, Agrawal Ganesh Kumar, Shioda Seiji, Fukumoto Manabu, Rakwal Randeep

机构信息

From the Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan (Hayashi and Fukumoto); Research Reactor Institute, Kyoto University, Osaka, Japan (Hayashi, Imanaka, and Fukutani); the Department of Anatomy I, School of Medicine, Showa University, Shinagawa, Tokyo, Japan (Shibato, Shioda, and Rakwal); the Laboratory of Exercise Biochemistry & Neuroendocrinology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan (Shibato); the Seoul Center, Korea Basic Science Institute (KBSI), Seoul, South Korea (Cho); the Environmental Stress Mechanisms Section, Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan (Kubo); the Plant Genome Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences (NIAS), Tsukuba, Ibaraki, Japan (Kikuchi and Satoh); the Laboratory of International Epidemiology, Center for International Cooperation, Dokkyo Medical University , Tochigi, Japan (Kimura); 91372-7 Kusabana, Akiruno, Tokyo, Japan (Ozawa); the Quantam Energy Applications, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima, Japan (Endo); the Office Brain, Tama Tsurumaki, Tokyo, Japan (Ichikawa); the Research Laboratory for Biotechnology and Biochemistry (RLABB), Kathmandu, Nepal (Agrawal and Rakwal); the GRADE Academy Private Limited, Birgunj, Nepal (Agrawal and Rakwal); and the Organization for Educational Initiatives, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8577, Japan (Rakwal).

出版信息

J Hered. 2014 Sep-Oct;105(5):723-38. doi: 10.1093/jhered/esu025.

DOI:10.1093/jhered/esu025

PMID:25124817

Abstract

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 (6h) 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.

摘要

2012年夏天，即2011年3月福岛第一核电站发生核事故一年后，我们在日本福岛相马村一个高污染区域研究了伽马辐射对水稻的影响。我们调查了暴露于高达4微希沃特每小时的连续低剂量伽马辐射下的健康水稻幼苗的形态和分子变化，该剂量约为自然本底水平的80倍。伽马射线照射后，通过逆转录聚合酶链反应（RT-PCR）检测了参与DNA复制/修复、氧化应激、光合作用以及防御/应激功能的特定基因的表达谱，结果显示这些基因在3天（6、12、24、48和72小时）内的叶片中呈现出随时间变化的差异表达。例如，水稻增殖细胞核抗原（OsPCNA）信使核糖核酸（mRNA）在6、12和24小时迅速增加，这表明水稻细胞通过激活参与DNA修复机制的基因来应对辐射应激。在72小时时，与苯丙烷类途径相关的基因（OsPAL2）和细胞死亡相关基因（OsPR1oa）被强烈诱导，表明防御/应激反应被激活。接下来，我们在早期（6小时）和晚期（72小时）使用定制的水稻全基因组4×44K DNA微阵列对转录组进行了分析。低水平伽马辐射对水稻叶片基因表达产生了差异调节（6小时时诱导44,81个基因，抑制3,740个基因；72小时时诱导2,291个基因，抑制1,474个基因），差异倍数至少为2倍。利用上调和下调程度高的基因列表，MapMan生物信息学工具生成了细胞对伽马射线照射反应中早期和晚期途径的示意图。大量伽马辐射响应基因的清单为水稻新的调控过程提供了新信息。