A sacrifice-for-survival mechanism protects root stem cell niche from chilling stress

Chilling to 4° induces cell death in a subset of cells at the Arabidopsis root tip, the CSCDs (columella stem cell daughters, located just distal to the quiescent center). Hong et al. show that this cell death is dependent on cell division and that it is an active, programmed response. Blocking this cell death renders the root more sensitive to chilling; therefore these cells are sacrificed for the root’s survival. This response is auxin-mediated, and affects auxin transporters and auxin distribution. The authors show that CSCD death leads to the re-establishment of the auxin maximum in the quiescent center and protects the stem cells.  Cell  10.1016/j.cell.2017.06.002