Spike-in heavy labeled protein lysate was generated by culturing SCN slices for 6 week in the precense of heavy arginine and lysine. SCN slices where harvested at 5 diffrent time points during one circadian cycle. The SCN slices where lysed and spiked with heavy SCN lysate. The samples were processed with the FASP protocol and and proteins quantified by LC-MS/MS using the MaxQuant software. To identify proteins with a circadian change in abundance with use JTK-cycle.