R-loop coupled chromatin regulation (360G-Wellcome-210654_Z_18_Z)

Non-canonical chromatin structures are emerging as important components of gene regulation. One example, RNA-DNA hybrid structures known as R-loops, occur frequently in many genomes. Initially studied with respect to genome instability, they have now been linked to transcriptional regulation, heterochromatin formation and recombination. But exactly what regulates R-loop dynamics, and how R-loops influence local chromatin states to affect a wide range of chromatin processes is still poorly understood. Deriving mechanistic understanding of R-loops from genome wide analyses is difficult. We will therefore focus on one functionally important R-loop and exploit a genetically tractable system and a wealth of information to develop deep mechanistic understanding into the regulation and role of an R-loop. We will identify novel factors that stabilize and resolve the R-loop, and establish how their functions are integrated. We will investigate whether the R-loop sets up a transcription-replication conflict that propagates heterochromatinization of the locus, thus setting the expression state. We will also dissect if R-loop dynamics and a gene loop influence promoter dominance to co-ordinate sense and antisense transcription. Active collaborations will enable a broad set of approaches to be used and concepts to be compared between organisms.