Unlocking the structure, mechanism and cellular assembly of key multiprotein complexes in human gene transcription. (360G-Wellcome-106115_Z_14_Z)

Human DNA contains ~20,000 genes, giving rise to ~100,000 proteins including isoforms andvariants. This enormous complexity is exploited by the cell to intricately assemble transient andstable multiprotein complexes, critical for cell homeostasis and development, in both health anddisease.Understanding structure is vital to explaining protein function and fundamental to drugdiscovery. Knowledge has improved dramatically over the past decades due to an enormousincrease in the number of structural analyses of individual proteins. Much less is known aboutmultiprotein complexes, often due to technical challenges in their provision and analysis, whichhave yet to be fully resolved.An essential first step in biogenesis is gene transcription. In humans, this process isregulated by complexes comprising often ten or more subunits, which arrange insuperstructures that cooperate at the interface of chromatin, fine-tuned by activating andrepressing modalities.How does the cell manage such complexity? How does it decide when to express whichgenes, and what are the functional architectures involved? How are proteins assembled intomultiprotein complexes, and what are the factors that assist in this process? The same proteinsmay exist in distinct complexes; are there specific mechanisms controlling their commitment?How do errors occur and how can we correct them?These questions are central to biology, which I plan to address in this proposal. We willstudy the archetypical general transcription factor complex TFIID, a multiprotein co-activator,SAGA (Spt-Ada-GCN5-acetyl-transferase) and a multiprotein co-repressor, NuRD (NucleosomeRemodeling and Deacetylation complex) in a comprehensive, integrated approach. As we havedone in the past, we expect to develop innovative tools in the process.My vision is to understand the cellular mechanisms of these protein machines, theirassembly process from gene to functional complex, their interdependence in gene regulationand the factors that control them. I aim to provide and roll-out tools and technologies requiredfor addressing questions of such complexity on a (more) routine basis. Understanding thesemechanisms will clarify how malfunctions can lead to pathologies. This in turn will help developstrategies for the design of new therapeutic interventions.