Department of Plant Biology, University of California Davis, 1 Shields Avenue, Davis, California 95616.
Department of Plant Biology, University of California Davis, 1 Shields Avenue, Davis, California 95616
Plant Physiol. 2018 Feb;176(2):1665-1675. doi: 10.1104/pp.17.01274. Epub 2017 Dec 8.
In Arabidopsis, DNA damage-induced programmed cell death is limited to the meristematic stem cell niche and its early descendants. The significance of this cell-type-specific programmed cell death is unclear. Here, we demonstrate in roots that it is the programmed destruction of the mitotically compromised stem cell niche that triggers its regeneration, enabling growth recovery. In contrast to wild-type plants, plants, which are defective in damage-induced programmed cell death, maintain the cell identities and stereotypical structure of the stem cell niche after irradiation, but these cells fail to undergo cell division, terminating root growth. We propose DNA damage-induced programmed cell death is employed by plants as a developmental response, contrasting with its role as an anticarcinogenic response in animals. This role in plants may have evolved to restore the growth of embryos after the accumulation of DNA damage in seeds.
在拟南芥中，DNA 损伤诱导的程序性细胞死亡仅限于分生组织干细胞龛及其早期后代。这种细胞类型特异性程序性细胞死亡的意义尚不清楚。在这里，我们在根中证明，正是有丝分裂受损的干细胞龛的程序性破坏触发了它的再生，从而实现了生长的恢复。与野生型植物相比，在辐射后，损伤诱导的程序性细胞死亡有缺陷的 植物仍然保持干细胞龛的细胞特征和典型结构，但这些细胞不能进行细胞分裂，从而终止根的生长。我们提出，植物中的 DNA 损伤诱导的程序性细胞死亡被用作一种发育反应，与动物中的作为抗癌反应的作用形成对比。在植物中，这种作用可能是为了在种子中积累 DNA 损伤后恢复胚胎的生长而进化而来的。
