Molecular Cogs: Interplay between Circadian Clock and Cell Cycle

The transcriptional core clock machinery controls the expression of numerous cell cycle regulators and many cell cycle proteins display time-of-the-day abundance. Circadian orchestration of the cell cycle may have conferred a selective advantage during evolution to capitalize environmental resources for cell division or to separate two incompatible processes in time when spatial segregation was impossible. Cell cycle proteins/steps could affect the phase and amplitude of circadian rhythms, indicating bidirectional control between these two oscillators. The core clock and cell cycle machineries are regulated at the post-translational level by a common set of enzymes. Therefore, post-translational integration of metabolic and environmental cues may affect both oscillators. The cell cycle and the circadian clock operate as biological oscillators whose timed functions are tightly regulated. Accumulating evidence illustrates the presence of molecular links between these two oscillators. This mutual interplay utilizes various coupling mechanisms, such as the use of common regulators. The connection between these two cyclic systems has unique interest in the context of aberrant cell proliferation since both of these oscillators are frequently misregulated in cancer cells. Further studies will provide deeper understanding of the detailed molecular connections between the cell cycle and the circadian clock and may also serve as a basis for the design of innovative therapeutic strategies. The cell cycle and the circadian clock operate as biological oscillators whose timed functions are tightly regulated. Accumulating evidence illustrates the presence of molecular links between these two oscillators. This mutual interplay utilizes various coupling mechanisms, such as the use of common regulators. The connection between these two cyclic systems has unique interest in the context of aberrant cell proliferation since both of these oscillators are frequently misregulated in cancer cells. Further studies will provide deeper understanding of the detailed molecular connections between the cell cycle and the circadian clock and may also serve as a basis for the design of innovative therapeutic strategies.