Cohen, I.; Hak, H.; Perez-Sancho, J.; Spiegelman, Z.; Efroni, I.

The excision of the root tip, including the stem cell niche, triggers rapid regeneration from remnant cells in the stump. In plants, cell identity relies on positional information transported through cytoplasmatic bridges known as plasmodesmata. However, how such information is reset to allow the regeneration of lost identities is unknown. Here, we show that the movement of mobile signals is temporarily restricted near the incision site and that regeneration-induced members of the LATERAL ORGAN DOMAIN (LBD) plant-specific developmental regulators are necessary and sufficient for this restriction. Regeneration was disrupted in high-order lbd mutants but was restored by transient localized plasmodesmata closure. We propose that LBD-mediated modulation of intercellular connectivity is crucial for plant regeneration and may have widespread roles in de novo pattern formation.