Stefanie
ROSA

My group investigates how chromatin dynamics within the plant nucleus shape gene expression and preserve genome integrity. Because nuclear processes are often heterogeneous across cells, we are moving beyond population-averaged measurements toward quantitative, single-cell and single-molecule approaches. A key part of our work is therefore to develop and apply tools that improve the spatial and temporal resolution with which molecular processes can be dissected in living plants. In genome stability, we combine quantitative live-cell fluorescence imaging, single-molecule RNA labeling, and molecular genetics to uncover how chromatin mobility changes during DNA damage, identify factors that regulate these dynamics, and determine how altered mobility affects repair and long-term genome stability. In gene regulation, we examine how 3D nuclear organization complements epigenetic mechanisms to enforce stable gene silencing. Polycomb Group (PcG) proteins reshape local chromatin and promote long-range interactions that contribute to nuclear architecture, yet how these layers of regulation mechanistically reinforce each other remains unclear. We address the cause-consequence relationship between Polycomb-mediated repression and subnuclear chromatin organization, linking chromatin structure to transcriptional states.