Wound healing in plant tissues, consisting of rigid cell wall-encapsulated cells, represents a considerable challenge and occurs through largely unknown mechanisms distinct from those in animals. Owing to their inability to migrate, plant cells rely on targeted cell division and expansion to regenerate wounds. Strict coordination of these wound-induced responses is essential to ensure efficient, spatially restricted wound healing. Single-cell tracking by live imaging allowed us to gain mechanistic insight into the wound perception and coordination of wound responses after laser-based wounding in Arabidopsis root. We revealed a crucial contribution of the collapse of damaged cells in wound perception and detected an auxin increase specific to cells immediately adjacent to the wound. This localized auxin increase balances wound-induced cell expansion and restorative division rates in a dose-dependent manner, leading to tumorous overproliferation when the canonical TIR1 auxin signaling is disrupted. Auxin and wound-induced turgor pressure changes together also spatially define the activation of key components of regeneration, such as the transcription regulator ERF115. Our observations suggest that the wound signaling involves the sensing of collapse of damaged cells and a local auxin signaling activation to coordinate the downstream transcriptional responses in the immediate wound vicinity.

植物组织中的伤口愈合，由刚性细胞壁包裹的细胞组成，是一个相当大的挑战，并且通过与动物不同的很大程度上未知的机制发生。由于它们无法迁移，植物细胞依靠有针对性的细胞分裂和扩张来再生伤口。这些伤口诱导反应的严格协调对于确保有效的、空间受限的伤口愈合至关重要。通过实时成像进行单细胞跟踪使我们能够深入了解拟南芥激光损伤后伤口感知和伤口反应的协调根。我们揭示了受损细胞在伤口感知中崩溃的关键贡献，并检测到与伤口紧邻的细胞特有的生长素增加。这种局部生长素增加以剂量依赖的方式平衡了伤口诱导的细胞扩增和恢复性分裂率，当典型的 TIR1 生长素信号被破坏时，会导致肿瘤过度增殖。生长素和伤口诱导的膨胀压力变化一起也在空间上定义了再生关键成分的激活，例如转录调节因子 ERF115。我们的观察表明，伤口信号涉及感知受损细胞的崩溃和局部生长素信号激活以协调紧邻伤口附近的下游转录反应。