title: Gene-specific requirement of RNA polymerase II CTD phosphorylation.
abstract: The largest subunit of RNA polymerase II, Rpb1, contains an unusual C-terminal domain (CTD) composed of numerous repeats of the YSPTSPS consensus sequence. This sequence is the target of post-translational modifications such as phosphorylation, glycosylation, methylation and transitions between stereoisomeric states, resulting in a vast combinatorial potential referred to as the CTD code. In order to gain insight into the biological significance of this code, several studies recently reported the genome-wide distribution of some of these modified polymerases and associated factors in either fission yeast (Schizosaccharomyces pombe) or budding yeast (Saccharomyces cerevisiae). The resulting occupancy maps reveal that a general RNA polymerase II transcription complex exists and undergoes uniform transitions from initiation to elongation to termination. Nevertheless, CTD phosphorylation dynamics result in a gene-specific effect on mRNA expression. In this review, we focus on the gene-specific requirement of CTD phosphorylation and discuss in more detail the case of serine 2 phosphorylation (S2P) within the CTD, a modification that is dispensable for general transcription in fission yeast but strongly affects transcription reprogramming and cell differentiation in response to environmental cues. The recent discovery of Cdk12 as a genuine CTD S2 kinase and its requirement for gene-specific expression are discussed in the wider context of metazoa.
authors.affiliation: Namur Research College-NARC, Rue de Bruxelles 61, 5000 Namur, Belgium.
authors.forename: Julie
authors.initials: J
authors.lastname: Drogat
authors.forename: Damien
authors.initials: D
authors.lastname: Hermand
mesh_terms: D015966:Gene Expression Regulation, Fungal; D008954:Models, Biological; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D012319:RNA Polymerase II / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D012568:Schizosaccharomyces / Q000201:enzymology* / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D012319:RNA Polymerase II