PT  - JOURNAL ARTICLE
AU  - Durrant, Matthew
AU  - Boyer, Justin
AU  - Baldwin, Ian T.
AU  - Xu, Shuqing
TI  - An evolutionary hourglass of herbivore-induced transcriptomic responses in <em>Nicotiana attenuata</em>
AID  - 10.1101/034603
DP  - 2016 Jan 01
TA  - bioRxiv
PG  - 034603
4099  - http://biorxiv.org/content/early/2016/03/07/034603.short
4100  - http://biorxiv.org/content/early/2016/03/07/034603.full
AB  - Herbivore induced defences are robust, evolve rapidly and activated in plants when specific elicitors, frequently found in the herbivores’ oral secretions (OS) are introduced into wounds during attack. How these complex induced defences evolve remains unclear. Here, we show that herbivore-induced transcriptomic responses in a wild tobacco, Nicotiana attenuata, display an evolutionary hourglass: the pattern that characterises the transcriptomic evolution of embryogenesis in animals, plants, and fungi. While relatively young and rapidly evolving genes involved in signal perception and processing to regulate defence metabolite biosynthesis are recruited both early (1 h) and late (9-21 h) in the defence elicitation process, a group of highly conserved and older genes involved in transcriptomic regulation are activated in the middle stage (5 h). The appearance of the evolutionary hourglass architecture in both developmental and defence elicitation processes may reflect the importance of robustness and evolvability in the signalling of these important biological processes.