Molecular Biology and Genomics Laboratory, Department of Botany, Berhampur University Berhampur, India.
Front Plant Sci. 2014 Jun 5;5:256. doi: 10.3389/fpls.2014.00256. eCollection 2014.
In the current study, we studied the role of signal transduction in aluminum (Al(3+))-induced DNA damage and adaptive response in root cells of Allium cepa L. The root cells in planta were treated with Al(3+) (800 μM) for 3 h without or with 2 h pre-treatment of inhibitors of mitogen-activated protein kinase (MAPK), and protein phosphatase. Also, root cells in planta were conditioned with Al(3+) (10 μM) for 2 h and then subjected to genotoxic challenge of ethyl methane sulfonate (EMS; 5 mM) for 3 h without or with the pre-treatment of the aforementioned inhibitors as well as the inhibitors of translation, transcription, DNA replication and repair. At the end of treatments, roots cells were assayed for cell death and/or DNA damage. The results revealed that Al(3+) (800 μM)-induced significant DNA damage and cell death. On the other hand, conditioning with low dose of Al(3+) induced adaptive response conferring protection of root cells from genotoxic stress caused by EMS-challenge. Pre-treatment of roots cells with the chosen inhibitors prior to Al(3+)-conditioning prevented or reduced the adaptive response to EMS genotoxicity. The results of this study suggested the involvement of MAPK and DNA repair network underlying Al-induced DNA damage and adaptive response to genotoxic stress in root cells of A. cepa.
在当前的研究中，我们研究了信号转导在铝（Al(3+））诱导的 DNA 损伤和洋葱根细胞适应反应中的作用。在没有或有丝裂原活化蛋白激酶（MAPK）和蛋白磷酸酶抑制剂预处理的情况下，将植物中的根细胞用 Al(3+）（800 μM）处理 3 小时。此外，将植物中的根细胞用 Al(3+）（10 μM）预处理 2 小时，然后用乙基甲磺酸（EMS；5 mM）进行遗传毒性挑战 3 小时，没有或有上述抑制剂以及翻译、转录、DNA 复制和修复抑制剂的预处理。在处理结束时，检测根细胞的细胞死亡和/或 DNA 损伤。结果表明，Al(3+）（800 μM）诱导显著的 DNA 损伤和细胞死亡。另一方面，用低剂量的 Al(3+）预处理诱导适应性反应，使根细胞免受 EMS 挑战引起的遗传毒性应激的保护。在用 Al(3+）预处理之前，用选定的抑制剂预处理根细胞可防止或减少对 EMS 遗传毒性的适应性反应。这项研究的结果表明，MAPK 和 DNA 修复网络参与了 Al 诱导的 DNA 损伤和洋葱根细胞对遗传毒性应激的适应反应。
