Practice question

CLAVATA family comprising CLV1, CLV2, CLV3, and CORYNE/CRN forms conserved receptor-ligand module regulating stem cell homeostasis in shoot and floral meristems across flowering plants. CLV3 peptide secreted from apical stem cells activates CLV1/CLV2-CRN receptor complexes in deeper layers to restrict WUS expression to small organizer domain. WUS in turn sustains stem cells and stimulates CLV3 expression completing circular feedback. Balanced negative regulation ensures appropriate meristem dimensions by controlling number of pluripotent cells versus cells recruited into leaf or floral organ primordia, integrating peptide signaling with cytokinin, auxin, and HAM factors.