PT  - JOURNAL ARTICLE
AU  - Klaus Brackmann
AU  - Virginie Jouannet
AU  - Jiyan Qi
AU  - Theresa Schlamp
AU  - Karin Grünwald
AU  - Pablo Sanchez
AU  - Thomas Greb
TI  - Spatial specificity of auxin responses coordinates wood formation
AID  - 10.1101/142885
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 142885
4099  - http://biorxiv.org/content/early/2017/05/27/142885.short
4100  - http://biorxiv.org/content/early/2017/05/27/142885.full
AB  - Spatial organization of signaling events of the phytohormone auxin is fundamental for maintaining a dynamic transition from plant stem cells to differentiated descendants. The cambium, the stem cell niche mediating wood formation, fundamentally depends on auxin signaling but its exact role and spatial organization is obscure. Here, we show that, while auxin signaling levels increase in differentiating cambium descendants, a moderate level of signaling in cambial stem cells is essential for cambium activity. We identify the auxin-dependent transcription factor ARF5/MONOPTEROS to cell-autonomously restrict the number of stem cells by attenuating the activity of the stem cell promoting WOX4 gene. In contrast, ARF3 and ARF4 function as cambium activators in a redundant fashion from outside of WOX4-expressing cells. Our results reveal an influence of auxin signaling on distinct cambium features by specific signaling components and allow the conceptual integration of plant stem cell systems with distinct anatomies.