title: Circadian control of jasmonates and salicylates: the clock role in plant defense.
abstract: Plants have evolved robust mechanisms to perceive and respond to diverse environmental stimuli.  The plant phytohormones jasmonates and salicylates play key roles in activating biotic stress response pathways. Recent findings demonstrate that basal levels of both jasmonates and salicylates in Arabidopsis are under the control of the circadian clock and that clock-controlled jasmonate accumulation may underlie clock- and jasmonate-dependent enhanced resistance of Arabidopsis to Trichoplusia ni (cabbage looper), a generalist herbivore. Here we summarize these findings and provide further evidence that a functional plant circadian clock is required for optimal herbivore defense in Arabidopsis.  When given a choice to feed on wild-type plants or arrhythmic transgenics, T. ni prefer plants lacking robust circadian rhythms. Altogether these data provide strong evidence for circadian clock enabling anticipation of herbivore attack and thus contributing to overall plant fitness.
authors.affiliation: Biochemistry and Cell Biology; Rice University; Houston, TX USA.
authors.forename: Danielle
authors.initials: D
authors.lastname: Goodspeed
authors.affiliation: Biochemistry and Cell Biology; Rice University; Houston, TX USA.
authors.forename: E Wassim
authors.initials: EW
authors.lastname: Chehab
authors.affiliation: Biochemistry and Cell Biology; Rice University; Houston, TX USA.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Covington
authors.affiliation: Biochemistry and Cell Biology; Rice University; Houston, TX USA.
authors.forename: Janet
authors.initials: J
authors.lastname: Braam
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000378:metabolism* / Q000502:physiology*; D057906:Circadian Clocks / Q000235:genetics / Q000502:physiology*; D003517:Cyclopentanes / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D060434:Herbivory / Q000502:physiology; D006790:Host-Parasite Interactions; D054883:Oxylipins / Q000378:metabolism*; D012459:Salicylates / Q000378:metabolism*
chemical_list: D003517:Cyclopentanes; D054883:Oxylipins; D012459:Salicylates; C011006:jasmonic acid
keywords: Arabidopsis thaliana; Trichoplusia ni; biotic stress; circadian rhythm; herbivory; jasmonic acid; plant resistance; plant-insect interaction; salicylic acid