A Molecular Framework for Auxin-Controlled Homeostasis of Shoot Stem Cells in Plant Zhong Zhaoa a School of Life Sciences, University of Science and Technology of China Abstract The classic phytohormone auxin plays essential roles in priming meristematic cell differentiation in the shoot apical meristem to promote lateral organ initiation. Recently, several lines of evidence have suggested that auxin not only is transported to new primordia but also descends in stem cells in the central zone. However, the function of auxin in stem cell regulation has remained elusive. Here, we show that auxin signaling in stem cells is least in part, by / (MP), which AUXIN RESPONSE FACTOR5 MONOPTEROS directly represses the transcription of DORNROSCHEN/ENHANCER OF SHOOT (DRN/ESR1). expressed in stem cells positively regulates REGENERATION 1 DRN CLV3 expression and has important meristematic functions. Our results provide a mechanistic framework for auxin control of shoot stem cell homeostasis and demonstrate how auxin differs in the control of plant stem cell maintenance and differentiation.
A Molecular Framework for Auxin-Controlled Homeostasis of Shoot Stem Cells in Plant Zhong Zhaoa a School of Life Sciences, University of Science and Technology of China Abstract The classic phytohormone auxin plays essential roles in priming meristematic cell differentiation in the shoot apical meristem to promote lateral organ initiation. Recently, several lines of evidence have suggested that auxin not only is transported to new primordia but also descends in stem cells in the central zone. However, the function of auxin in stem cell regulation has remained elusive. Here, we show that auxin signaling in stem cells is least in part, by AUXIN RESPONSE FACTOR5 / MONOPTEROS (MP), which directly represses the transcription of DORNROSCHEN/ENHANCER OF SHOOT REGENERATION 1 (DRN/ESR1). DRN expressed in stem cells positively regulates CLV3 expression and has important meristematic functions. Our results provide a mechanistic framework for auxin control of shoot stem cell homeostasis and demonstrate how auxin differs in the control of plant stem cell maintenance and differentiation.