TY - JOUR TI - Robust, coherent, and synchronized circadian clock-controlled oscillations along Anabaena filaments AU - Arbel-Goren, Rinat AU - Buonfiglio, Valentina AU - Di Patti, Francesca AU - Camargo, Sergio AU - Zhitnitsky, Anna AU - Valladares, Ana AU - Flores, Enrique AU - Herrero, Antonia AU - Fanelli, Duccio AU - Stavans, Joel A2 - Walczak, Aleksandra M A2 - Krishna, Sandeep A2 - Jensen, Mogens H VL - 10 PY - 2021 DA - 2021/03/22 SP - e64348 C1 - eLife 2021;10:e64348 DO - 10.7554/eLife.64348 UR - https://doi.org/10.7554/eLife.64348 AB - Circadian clocks display remarkable reliability despite significant stochasticity in biomolecular reactions. We study the dynamics of a circadian clock-controlled gene at the individual cell level in Anabaena sp. PCC 7120, a multicellular filamentous cyanobacterium. We found significant synchronization and spatial coherence along filaments, clock coupling due to cell-cell communication, and gating of the cell cycle. Furthermore, we observed low-amplitude circadian oscillatory transcription of kai genes encoding the post-transcriptional core oscillatory circuit and high-amplitude oscillations of rpaA coding for the master regulator transducing the core clock output. Transcriptional oscillations of rpaA suggest an additional level of regulation. A stochastic one-dimensional toy model of coupled clock cores and their phosphorylation states shows that demographic noise can seed stochastic oscillations outside the region where deterministic limit cycles with circadian periods occur. The model reproduces the observed spatio-temporal coherence along filaments and provides a robust description of coupled circadian clocks in a multicellular organism. KW - Circadian clock KW - Anabaena KW - cell-cell communication KW - demographic noise KW - stochastic oscillations KW - clock arrays JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -