CSL ChIP-seq

The expression of a large proportion of the fission yeast genome changes periodically with the cell cycle. Several key transcription factors have been identified that regulate these oscillating and interdependent waves of gene expression. However, for a significant number of cell cycle-regulated genes the regulator(s) driving these oscillations remain unknown. Cbf11 and Cbf12, the fission yeast CSL transcription factors, have been implicated in the regulation of cell cycle progression, yet the details of their functioning are poorly understood. Using a combination of transcriptome profiling and genome-wide mapping of CSL-DNA interactions we have identified a comprehensive set of CSL-regulated genes. Our data indicate that Cbf11 and Cbf12 contribute directly and indirectly to the regulation of periodically expressed genes in fission yeast. We show that during S phase/cytokinesis Cbf11 directly activates the transcription of several periodic genes required in the cell to prevent catastrophic mitosis. In agreement with these findings, multiple aspects of cell cycle progression are perturbed when CSL cellular levels are genetically manipulated. We have identified Cbf11 as a novel cell cycle phase-specific activator of genes required for proper coordination of cell and nuclear division, and prevention of catastrophic mitosis in fission yeast.