A jasmonate signaling network activates root stem cells and promotes regeneration ($) (Cell)

Plants possess plasticity for regeneration of organs after damage by physical, biotic or abiotic stress. The mitotically less-active organizer cells, quiescent center (QC) and surrounding initials form the stem cell niche, which is known to play a very important role in activation of the regeneration process in animals as well as in plants. In the Arabidopsis regeneration activation pathway, the RETINOBLASTOMA RELATED (RBR)-SCARECROW (SCR)-SHORT ROOT (SHR) protein network regulates cell division in root stem cells. Stress hormones such as JA, abscisic acid and ethylene can regulate cell division and may take part in the regeneration process. Here, Zhou et al. show that the stress hormone JA has a conspicuous role in activation of regeneration by taking part in the established RBR-SCR pathway. The authors studied the JA response after wounding created by laser ablation or resection, and after biotic damage by nematode herbivory. The signaling pathway induced by JA includes AP2/ERF family transcription factors ERF115 and ERF109, which control the cell division. In summary, this study shows the important role of JA in cell regeneration pathway for roots.  (Summary by Mugdha Sabale) Cell 10.1016/j.cell.2019.03.006