Project description:Alternative splicing of pre-mRNA is a prominent mechanism to generate protein diversity, yet its regulation is poorly understood. Here, we demonstrate a direct role for histone modifications in alternative splicing. We find distinctive histone modification signatures which correlate with splicing outcome in a set of human genes. Modulation of histone modifications causes splice site switching. The mechanism for histone-mediated splice site selection involves a histone mark which is read by a chromatin protein, which in turn recruits a splicing regulator. These results outline an adaptor system for reading of histone marks by the pre-mRNA splicing machinery.
Project description:Alternative splicing of pre-mRNA is a prominent mechanism to generate protein diversity, yet its regulation is poorly understood. Here, we demonstrate a direct role for histone modifications in alternative splicing. We find distinctive histone modification signatures which correlate with splicing outcome in a set of human genes. Modulation of histone modifications causes splice site switching. The mechanism for histone-mediated splice site selection involves a histone mark which is read by a chromatin protein, which in turn recruits a splicing regulator. These results outline an adaptor system for reading of histone marks by the pre-mRNA splicing machinery. To obtain an estimate of how many PTB-dependent alternative splicing events are regulated by SET2/MRG15-mediated recruitment of PTB, we carried out a genomewide comparative analysis of alternative splicing in hMSC cells depleted of either SETD2, MRG15 or PTB using specific siRNAs, or mock-depleted using a control siRNA.
Project description:There are three major epigenetic mechanisms, DNA methylation, histone modifications, and ncRNAs. The histone is a key player in epigenetics, and the acetylation and methylation are their most common post-translational modifications (PTMs). These histone modifications have important roles in transcriptional regulation, DNA repair, DNA replication, alternative splicing and chromosome condensation. For example, we previously found that H3.3 lysine 36 trimethylation (H3.3K36me3) histone and its reader protein BS69 could work together to regulate pre-mRNA process. Therefore, in this study, we established in vitro histone acetylation, demethylation and methylation models, respectively, by using human lung, liver and colorectal cancer cells.