Department of Molecular Genetics, Centre for Research in Agricultural Genomics, Campus UAB, Edifici CRAG, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain.
BMC Plant Biol. 2011 May 19;11(1):91. doi: 10.1186/1471-2229-11-91.
Camptothecin is a plant alkaloid that specifically binds topoisomerase I, inhibiting its activity and inducing double stranded breaks in DNA, activating the cell responses to DNA damage and, in response to severe treatments, triggering cell death.
Comparative transcriptomic and proteomic analyses of maize embryos that had been exposed to camptothecin were conducted. Under the conditions used in this study, camptothecin did not induce extensive degradation in the genomic DNA but induced the transcription of genes involved in DNA repair and repressed genes involved in cell division. Camptothecin also affected the accumulation of several proteins involved in the stress response and induced the activity of certain calcium-dependent nucleases. We also detected changes in the expression and accumulation of different genes and proteins involved in post-translational regulatory processes.
This study identified several genes and proteins that participate in DNA damage responses in plants. Some of them may be involved in general responses to stress, but others are candidate genes for specific involvement in DNA repair. Our results open a number of new avenues for researching and improving plant resistance to DNA injury.
喜树碱是一种植物生物碱,它特异性地与拓扑异构酶 I 结合,抑制其活性并诱导 DNA 双链断裂,激活细胞对 DNA 损伤的反应,并且在严重处理的情况下,触发细胞死亡。
对暴露于喜树碱的玉米胚胎进行了比较转录组学和蛋白质组学分析。在本研究中使用的条件下,喜树碱不会诱导基因组 DNA 的广泛降解,但会诱导参与 DNA 修复的基因的转录,并抑制参与细胞分裂的基因。喜树碱还会影响几种参与应激反应的蛋白质的积累,并诱导某些依赖钙的核酸酶的活性。我们还检测到与翻译后调控过程相关的不同基因和蛋白质的表达和积累的变化。
本研究鉴定了参与植物 DNA 损伤反应的几个基因和蛋白质。其中一些可能参与一般的应激反应,但其他则是特定参与 DNA 修复的候选基因。我们的结果为研究和提高植物对 DNA 损伤的抗性开辟了许多新途径。