Autotrophic cyanobacteria use circadian clock systems to rhythmically regulate photosynthetic efficiency to adapt to the light-dark cycle on Earth. Here, the authors show that the oldest cyanobacterial clock-protein oscillator appears at approximately 2.2 Ga ago, and has been inherited by extant cyanobacteria.
- Atsushi Mukaiyama
- Yoshihiko Furuike
- Shuji Akiyama
