Epigenetic gene regulation
Eukaryotic transcription is dynamically regulated by post-translational modifications of histones, including phosphorylation, acetylation, ubiquitination and methylation. Histone methylations occur on tails and globular domains of histones and play important roles in regulation of transcription by RNA polymerase II (RNA PolII). Histone methylations have been implicated in diverse cellular processes, including X-chromosome inactivation, heterochromatin formation, and gene silencing. Importantly, histone methylations are directly linked to cancer development in humans.
Cells undergo rapid environmental changes in their natural conditions and must correspondingly change their gene expression patterns to adapt. This gene regulation is mainly carried out at the transcriptional level. Although transcriptional change in a steady state condition provides information of how a factor regulates transcription of a specific gene, it is important to consider how the kinetics of transcriptional responses can affect fitness. Regulation of gene expression dynamics is also critical during cell differentiation and development. Interestingly, many chromatin factors are dispensable for stem cell maintenance but they seem to be important during stem cell differentiation suggesting that a proper regulation of target genes during this period is critical for fate decisions of stem cells. We investigate how chromatin modifications and lincRNA transcription affect dynamics of RNA polymerase II(RNApII) transcription to coordinate cellular processes upon environmental changes.