Practice question

WOX5 WUSCHEL-related homeobox 5 transcription factor is exclusively expressed in quiescent center cells of root apical meristem functioning analogously to shoot WUS. It moves non-cell-autonomously to surrounding cortex/endodermis and columella initials repressing differentiation-promoting transcription factor CYCLING DOF FACTOR 4 and maintaining stem cell identity. WOX5 sustains PLT gradient, auxin homeostasis, and represses differentiation via local chromatin modifications. Its expression maintained by SHR/SCR and PLT feedback as well as auxin, illustrating conserved WOX-based organizing center mechanism preserving root stem cell reservoir enabling continuous indeterminate growth.