Prof. Dr. Robert Grosse (CIBSS-PI), Institute of Experimental and Clinical Pharmacology and Toxicology (Faculty of Medicine), University of Freiburg
It has only recently emerged that nuclear actin filaments can promote transcriptional reprogrammingi, immunological synapse signalling for immediate early gene regulation, DNA and heterochromatin repair as well as chromatin reorganization at mitotic exit. We had previously provided the first evidence that external signals and ligands promote rapid and transient assembly of nuclear actin networks in intact mammalian cells. We had further uncovered the principle that nuclear F-actin can reorganize chromatin in living, dividing cells. However, how precisely physiological ligands relay rapid nuclear actin assembly into direct chromatin dynamics is unknown. Further, whether and how such signal-regulated nuclear actin polymerization may interact with chromatin has not been investigated. Herein, by combining optogenetics with high-resolution live cell imaging of the nucleoskeleton, we will aim to unravel the mechanisms of rapid signal-regulated nuclear actin assembly and their functional impact on chromatin dynamics.