The Arabidopsis homeobox gene SHOOT MERISTEMLESS has cellular and meristem‐organisational roles with differential requirements for cytokinin and CYCD3 activity

• DOI: 10.1111/tpj.12198
• Publication Date: 2013-04-10T09:35:48Z
• Authors: Simon Scofield; Walter Dewitte; Jeroen Nieuwland; James A.H. Murray
• Keywords: Ectopic expression

Summary The A rabidopsis class‐1 KNOX gene SHOOT MERISTEMLESS ( STM ) encodes a homeodomain transcription factor essential for shoot apical meristem SAM formation and sustained activity. activates cytokinin CK biosynthesis in the , but extent to which function is mediated through unclear. Here we show that inhibits cellular differentiation endoreduplication, acting ‐inducible CYCD 3 cell cycle regulators, establishing mechanistic link control provides mitotic activity maintain pool of undifferentiated cells . Equivalent functions are revealed related genes KNAT 1/ BP 2 ectopic expression. also required proper organisation can induce de novo when expressed ectopically, even levels reduced or signaling impaired. This establishment be replaced by not despite its activation responses, suggesting promotion responses alone insufficient organisation. We propose has dual meristem‐organisational differentially represented family have differing requirements 3.