 Other components have been found to be expressed throughout the day and either directly or indirectly inhibit or activate a consequent element in the circadian circuit, thereby creating a complex, robust and flexible network of feedback loops.The morning-phase expression loop refers to the genes and proteins that regulate rhythms during the day in "A. thaliana".The two main genes are LHY and CCA1, which encode LHY and CCA1 transcription factors.