title: A laboratory simulation of Arabidopsis seed dormancy cycling provides new insight into its regulation by clock genes and the dormancy-related genes DOG1, MFT, CIPK23 and PHYA.
abstract: Environmental signals drive seed dormancy cycling in the soil to synchronize germination with the optimal time of year, a process essential for species' fitness and survival. Previous correlation of transcription profiles in exhumed seeds with annual environmental signals revealed the coordination of dormancy-regulating mechanisms with the soil environment. Here, we developed a rapid and robust laboratory dormancy cycling simulation. The utility of this simulation was tested in two ways: firstly, using mutants in known dormancy-related genes [DELAY OF GERMINATION 1 (DOG1), MOTHER OF FLOWERING TIME (MFT), CBL-INTERACTING PROTEIN KINASE 23 (CIPK23) and PHYTOCHROME A (PHYA)] and secondly, using further mutants, we test the hypothesis that components of the circadian clock are involved in coordination of the annual seed dormancy cycle. The rate of dormancy induction and relief differed in all lines tested. In the mutants, dog1-2 and mft2, dormancy induction was reduced but not absent. DOG1 is not absolutely required for dormancy. In cipk23 and phyA dormancy, induction was accelerated. Involvement of the clock in dormancy cycling was clear when mutants in the morning and evening loops of the clock were compared. Dormancy induction was faster when the morning loop was compromised and delayed when the evening loop was compromised.
authors.affiliation: School of Life Sciences, Wellesbourne Campus, University of Warwick, Warwick, Warwickshire, CV35 9EF, UK.
authors.forename: Steven
authors.identifier: http://orcid.org/0000-0003-2056-3858
authors.initials: S
authors.lastname: Footitt
authors.affiliation: Department of Biology, Faculty of Arts and Sciences, Evliya Celebi Campus, Dumlupınar University, TR-43100, Kütahya, Turkey.
authors.forename: Hülya
authors.initials: H
authors.lastname: Ölçer-Footitt
authors.affiliation: School of Life Sciences, Wellesbourne Campus, University of Warwick, Warwick, Warwickshire, CV35 9EF, UK.
authors.forename: Angela J
authors.initials: AJ
authors.lastname: Hambidge
authors.affiliation: School of Life Sciences, Wellesbourne Campus, University of Warwick, Warwick, Warwickshire, CV35 9EF, UK.
authors.forename: William E
authors.initials: WE
authors.lastname: Finch-Savage
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001683:Biological Clocks / Q000187:drug effects / Q000235:genetics*; D003198:Computer Simulation; D003624:Darkness; D060146:Ecotype; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D018525:Germination / Q000187:drug effects / Q000235:genetics; D062312:Islands; D009154:Mutation / Q000235:genetics; D057445:Plant Dormancy / Q000187:drug effects / Q000235:genetics*; D012621:Seasons; D013696:Temperature; D013997:Time Factors; D014158:Transcription, Genetic
chemical_list: D029681:Arabidopsis Proteins; D000040:Abscisic Acid
keywords: circadian clock; circannual rhythm; germination; thermal time