title: Integration of light and metabolic signals for stem cell activation at the shoot apical meristem.
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.
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Pfeiffer
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Denis
authors.initials: D
authors.lastname: Janocha
authors.affiliation: Department of Molecular Plant Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Yihan
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Medzihradszky
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Schöne
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Gabor
authors.initials: G
authors.lastname: Daum
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Takuya
authors.initials: T
authors.lastname: Suzaki
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Forner
authors.affiliation: Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Langenecker
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Eugen
authors.initials: E
authors.lastname: Rempel
authors.affiliation: Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Schmid
authors.affiliation: Department of Molecular Plant Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Wirtz
authors.affiliation: Department of Molecular Plant Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Rüdiger
authors.identifier: 0000-0002-6238-4818
authors.initials: R
authors.lastname: Hell
authors.affiliation: Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany.
authors.forename: Jan U
authors.identifier: 0000-0003-3667-187X
authors.initials: JU
authors.lastname: Lohmann
mesh_terms: D018506:Gene Expression Regulation, Plant / Q000528:radiation effects*; D008027:Light; D018519:Meristem / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects; D013234:Stem Cells / Q000378:metabolism* / Q000528:radiation effects*
keywords: <i>a. thaliana</i>; TOR kinase; WUSCHEL; developmental biology; light signaling; metabolic signaling; plant biology; stem cell activation; stem cells