Daily cycling of genome-wide histone methylation

Daily (circadian) clocks are essential for regulating and coordinating physiology in mammals. Modulation of local chromatin structure has been shown for only a small number of genes, principally thought to be directly modulated by Clock-mediated histone acetylation. Here we show that genome-wide changes of active and suppressive histone marks control global chromatin architecture over the day and night. Overall design: Examination of mouse liver tissue at 4 time-points around the clock in "free-running", continuous conditions (constant darkness, temperature and food available ad libitum).