Welz, Patrick-SimonZinna, Valentina M.Symeonidi, AikateriniKoronowski, Kevin B.Kinouchi, KenichiroSmith, Jacob G.Marín Guillén, InésCastellanos, AndrésFurrow, StephenAragón, FerránCrainiciuc, GeorgianaPrats, NeusMartín Caballero, JuanHidalgo, AndrésSassone-Corsi, PaoloAznar Benitah, Salvador2019-09-302020-05-302019-05-30https://hdl.handle.net/2445/141217Circadian rhythms control organismal physiology throughout the day. At the cellular level, clock regulation is established by a self-sustained Bmal1-dependent transcriptional oscillator network. However, it is still unclear how different tissues achieve a synchronized rhythmic physiology. That is, do they respond independently to environmental signals, or require interactions with each other to do so? We show that unexpectedly, light synchronizes the Bmal1-dependent circadian machinery in single tissues in the absence of Bmal1 in all other tissues. Strikingly, light-driven tissue autonomous clocks occur without rhythmic feeding behavior and are lost in constant darkness. Importantly, tissue-autonomous Bmal1 partially sustains homeostasis in otherwise arrhythmic and prematurely aging animals. Our results therefore support a two-branched model for the daily synchronization of tissues: an autonomous response branch, whereby light entrains circadian clocks without any commitment of other Bmal1-dependent clocks, and a memory branch using other Bmal1-dependent clocks to “remember” time in the absence of external cues.26 p.application/pdfengcc by-nc-nd (c) Welz et al., 2019http://creativecommons.org/licenses/by-nc-nd/3.0/es/Ritmes circadiarisFisiologiaCircadian rhythmsPhysiologyinfo:eu-repo/semantics/article2019-09-16info:eu-repo/semantics/openAccess3115062031398328