Project description:Dynamic post-translational modification of RNA polymerase II (RNAPII) coordinates the co-transcriptional recruitment of enzymatic complexes that regulate chromatin states and co-transcriptional processing of nascent RNA. Extensive phosphorylation of serine residues occurs at the structurally-disordered C-terminal domain (CTD) of the largest RNAPII subunit, which is composed of multiple heptapeptide repeats with consensus sequence Y1-S2-P3-T4-S5-P6-S7. Serine-5 and Serine-7 phosphorylation mark transcription initiation, whereas Serine-2 phosphorylation coincides with productive elongation. In vertebrates, the CTD has eight non-canonical substitutions of Serine-7 into Lysine-7, which can be acetylated (K7ac). Here, we describe for the first time mono- and di-methylation of CTD Lysine-7 residues (K7me1 and K7me2). K7me1 and K7me2 are observed during the earliest transcription stages and precede or accompany Serine-5 and Serine-7 phosphorylation. Genome wide mapping of 2 novel RNAPII post-translational modifications (CTD-K7me1 and CTD-K7me2) in mouse ES cells.
Project description:As Integrator is tightly associated with RNAPII-CTD, it is critical to understand how the RNAPII engaged and conducted within the active gene promoter for divergent transcription. We thus employed RNAPII ChIP-seq (Chromatin Immuno-precipitation with RNAPII antibody) to determine the distribution of the total RNAPII and its phosphorylation isoforms. Total RNA polymerase II and its carbon terminal phosphorylation(RNA polymerase II-ctd-Tyr-1，RNA polymerase II-ctd-ser-2) before and after INTS11 knockdown in HCT116-INTS11-AID cells changes chromatin immunoprecipitation DNA sequencing (ChIP-seq).
Project description:DYRK1A is a dosage-sensitive protein kinase that fulfills key roles during development and in tissue homeostasis, and its dysregulation results in human pathologies. DYRK1A is present in both the nucleus and cytoplasm of mammalian cells, although its nuclear function remains unclear. Genome-wide analysis of DYRK1A-associated loci reveals that the kinase is recruited preferentially to promoters of genes actively transcribed by RNA polymerase II (RNAPII), which are functionally associated with translation, RNA processing and cell cycle. DYRK1A-bound promoter sequences are highly enriched in a conserved palindromic motif, which is necessary to drive DYRK1A-dependent transcriptional activation. DYRK1A phosphorylates the carboxy-terminal domain (CTD) of RNAPII at Ser2 and Ser5. Depletion of DYRK1A results in reduced association of RNAPII at the target promoters as well as hypophosphorylation of the CTD of RNAPII along the target gene bodies. Accordingly, we propose that DYRK1A acts as a transcriptional regulator by acting as a novel CTD kinase. Occupancy of the kinase DYRK1A in two different cell lines and in two different growing conditions.
