Integration of light and metabolic signals for stem cell activation at the shoot apical meristem
- Heidelberg University, Germany
- University of Tsukuba, Japan
- Max Planck Institute for Developmental Biology, Germany
- Umeå University, Sweden
Abstract
A major feature of embryogenesis is the specification of stem cell systems, but in contrast to the situation in most animals, plant stem cells remain quiescent until the postembryonic phase of development. Here, we dissect how light and metabolic signals are integrated to overcome stem cell dormancy at the shoot apical meristem. We show on the one hand that light is able to activate expression of the stem cell inducer WUSCHEL independently of photosynthesis and that this likely involves inter-regional cytokinin signaling. Metabolic signals, on the other hand, are transduced to the meristem through activation of the TARGET OF RAPAMYCIN (TOR) kinase. Surprisingly, TOR is also required for light signal dependent stem cell activation. Thus, the TOR kinase acts as a central integrator of light and metabolic signals and a key regulator of stem cell activation at the shoot apex.
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© 2016, Pfeiffer et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Integration of light and metabolic signals for stem cell activation at the shoot apical meristem
eLife 5:e17023.
https://doi.org/10.7554/eLife.17023
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