Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium.
Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium.
Nat Plants. 2016 Oct 31;2(11):16165. doi: 10.1038/nplants.2016.165.
Regeneration of a tissue damaged by injury represents a physiological response for organ recovery. Although this regeneration process is conserved across multicellular taxa, plants appear to display extremely high regenerative capacities, a feature widely used in tissue culture for clonal propagation and grafting. Regenerated cells arise predominantly from pre-existing populations of division-competent cells; however, the mechanisms by which these cells are triggered to divide in response to injury remain largely elusive. Here, we demonstrate that the heterodimeric transcription factor complex ETHYLENE RESPONSE FACTOR115 (ERF115)-PHYTOCHROME A SIGNAL TRANSDUCTION1 (PAT1) sustains meristem function by promoting cell renewal after stem cell loss. High-resolution time-lapse imaging revealed that cell death promotes ERF115 activity in cells that are in direct contact with damaged cells, triggering divisions that replenish the collapsed stem cells. Correspondingly, the ERF115-PAT1 complex plays an important role in full stem cell niche recovery upon root tip excision, whereas its ectopic expression triggers neoplastic growth, correlated with activation of the putative target gene WOUND INDUCED DEDIFFERENTIATION1 (WIND1). We conclude that the ERF115-PAT1 complex accounts for the high regenerative potential of plants, granting them the ability to efficiently replace damaged cells with new ones.
组织损伤后的再生代表了器官恢复的生理反应。尽管这种再生过程在多细胞生物中是保守的，但植物似乎表现出极高的再生能力，这一特性广泛应用于组织培养中的无性繁殖和嫁接。再生细胞主要来自于具有分裂能力的预先存在的细胞群体；然而，这些细胞在受到损伤时被触发分裂的机制在很大程度上仍然难以捉摸。在这里，我们证明了二聚体转录因子复合物 ETHYLENE RESPONSE FACTOR115（ERF115）-PHYTOCHROME A SIGNAL TRANSDUCTION1（PAT1）通过促进干细胞丢失后的细胞更新来维持分生组织的功能。高分辨率延时成像显示，细胞死亡会促进与受损细胞直接接触的细胞中 ERF115 的活性，触发分裂以补充塌陷的干细胞。相应地，ERF115-PAT1 复合物在根尖切除后对整个干细胞生态位的完全恢复起着重要作用，而其异位表达会触发肿瘤生长，这与假定的靶基因 WOUND INDUCED DEDIFFERENTIATION1（WIND1）的激活有关。我们的结论是，ERF115-PAT1 复合物解释了植物的高再生潜力，使它们能够有效地用新的细胞替代受损的细胞。
