School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala 695551, India.
Plant Developmental Biology, Wageningen University and Research Centre, Wageningen 6708PB, the Netherlands.
Cell Rep. 2019 Oct 8;29(2):453-463.e3. doi: 10.1016/j.celrep.2019.08.099.
A wide variety of multicellular organisms across the kingdoms display remarkable ability to restore their tissues or organs when they suffer damage. However, the ability to repair damage is not uniformly distributed throughout body parts. Here, we unravel the elusive mechanistic basis of boundaries on organ regeneration potential using root tip resection as a model and show that the dosage of gradient-expressed PLT2 transcription factor is the underlying cause. While transient downregulation of PLT2 in distinct set of plt mutant backgrounds renders meristematic cells incapable of regeneration, forced expression of PLT2 acts through auto-activation to confer regeneration potential to the cells undergoing differentiation. Surprisingly, sustained exposure to nuclear PLT2, beyond a threshold, leads to reduction of regeneration potential despite giving rise to longer meristem. Our studies reveal dosage-dependent role of gradient-expressed PLT2 in root tip regeneration and uncouple the size of an organ from its regeneration potential.
多种生物在不同的生物界中表现出非凡的组织或器官损伤修复能力。然而，损伤修复能力在身体各部位的分布并不均匀。在这里，我们以根尖切除作为模型，揭示了器官再生潜力的限制的难以捉摸的机制基础，并表明梯度表达的 PLT2 转录因子的剂量是其潜在原因。虽然在不同的 plt 突变背景下瞬时下调 PLT2 会使分生细胞无法再生，但强制表达 PLT2 通过自动激活作用赋予正在分化的细胞再生潜力。令人惊讶的是，尽管核 PLT2 的持续暴露超过了阈值会导致再生潜力降低，但会导致分生组织变长。我们的研究揭示了梯度表达的 PLT2 在根尖再生中的剂量依赖性作用，并将器官的大小与其再生潜力分离开来。
