Mitotic transcription and waves of gene reactivation during mitotic exit

Gene expression during mitosis During mitosis, long-range interactions within chromosomes are lost, and many enhancers become inactive. It is generally thought that gene expression is silent at this time. However, transcription must be reactivated when cells reenter the cell cycle in order to maintain cell identity. Palozola et al. used a sensitive nascent RNA labeling and sequencing method to reveal low-level transcription of many genes in mitosis. Upon mitotic exit, the amplitude of gene expression was reestablished with basic cell functions prioritized over cell-specific genes. Thus, transcription itself may retain gene expression patterns through mitosis. Science , this issue p. 119