An evolutionary young defense metabolite influences the root growth of plants via the ancient TOR signaling pathway
Abstract
To optimize fitness a plant should monitor its metabolism to appropriately control growth and defense. Primary metabolism can be measured by the universally conserved TOR (Target of Rapamycin) pathway to balance growth and development with the available energy and nutrients. Recent work suggests that plants may measure defense metabolites to potentially provide a strategy ensuring fast reallocation of resources to coordinate plant growth and defense. There is little understanding of mechanisms enabling defense metabolite signaling. To identify mechanisms of defense metabolite signaling, we used glucosinolates, an important class of plant defense metabolites. We report novel signaling properties specific to one distinct glucosinolate, 3-hydroxypropylglucosinolate across plants and fungi. This defense metabolite, or derived compounds, reversibly inhibits root growth and development. 3-hydroxypropylglucosinolate signaling functions via genes in the ancient TOR pathway. If this event is not unique, this raises the possibility that other evolutionarily new plant metabolites may link to ancient signaling pathways.
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Funding
Danmarks Grundforskningsfond (DNRF99)
- Frederikke Gro Malinovsky
- Marie-Louise F Thomsen
- Sebastian J Nintemann
- Baptiste Bourgine
- Meike Burow
- Daniel J Kliebenstein
National Science Foundation (IOS 13391205)
- Daniel J Kliebenstein
National Science Foundation (MCB 1330337)
- Daniel J Kliebenstein
U.S. Department of Agriculture (CA-D-PLS-7033-H)
- Daniel J Kliebenstein
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Malinovsky 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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