FUNFACTs · Fundamental Understanding of shelteriN Function and Architecture on Chromatinized Telomeres

Telomeres protect chromosome ends from being mistaken for DNA damage. This task is orchestrated by the shelterin complex. Dysfunction of shelterin leads to genome instability and is implicated in cancer, premature ageing syndromes, and other telomere biology disorders. However, the structural organization of shelterin on its native chromatin substrate remains poorly understood. This limits our ability to link molecular architecture to biological function and disease. The FUNFACTs project addresses this gap by integrating advanced structural biology, chromatin biochemistry, and cell biology to reveal how shelterin binds, organizes, and protects telomeric chromatin.First, I will generate high-quality native and recombinant shelterin-chromatin assemblies and establish scalable protocols for their production (WP1). Second, I will obtain high-resolution structures using cryo-electron microscopy (cryo-EM) and cryo-electron tomography (cryo-ET), complemented by single-molecule fluorescence assays to determine whether shelterin remodels telomeric chromatin and how such changes contribute to protection (WP2). Finally, I will perform targeted mutagenesis, quantitative cellular assays, and detailed biochemical analyses to functionally validate structural models and clarify the mechanistic role of shelterin (WP3).This interdisciplinary strategy will deliver conceptual breakthroughs in chromosome end protection as well as broadly applicable methodologies. It will include protocols for multicomponent chromatin assembly, which is relevant to various genome processes. In line with the MSCA PF Work Programme, the project is expected to have a significant impact on my career, as it will provide top-level scientific training, foster international collaboration, and develop transferable skills. This will prepare me for a future research group leader position while generating knowledge with clear potential for impact in biomedical research and innovation.