Download MendeleyStructural basis of DNA-dependent coactivator recruitment by the tuft cell master regulator POU2F3.
Alpsoy, A., Ipsaro, J.J., Skopelitis, D., Pal, S., Chung, F.S., Carpenter, S., Desmarais, J.J., Wu, X.S., Chang, K., DiMare, M.T., Harten, E., Bergman, S., Kinney, J.B., Engelman, J.A., Bhang, H.C., Joshua-Tor, L., Vakoc, C.R.(2025) Cell Rep 44: 116572-116572
- PubMed: 41260223
- DOI: https://doi.org/10.1016/j.celrep.2025.116572
- Primary Citation of Related Structures:
9PFN, 9PFO, 9PFP - PubMed Abstract:
The transcription factor POU2F3 defines the identity of tuft cells and underlies a distinct molecular subtype of small cell lung cancer (SCLC). Although POU2F3 is considered undruggable, its activity critically depends on the coactivators OCA-T1 and OCA-T2. Here, we demonstrate that acute suppression of either POU2F3 or OCA-T1 induces regression of tuft cell-like SCLC xenografts in vivo. To explore the structural basis and druggability of this dependency, we determine crystal structures of POU2F3 bound to OCA-T1 or OCA-T2 in complex with DNA, revealing a tripartite, DNA-dependent interface. We further employ deep mutational scanning to assess the functional impact of 4,218 missense variants in POU2F3 and OCA-T1, uncovering both mutation-sensitive hotspots and structurally constrained regions critical for tumor cell fitness. These findings define a transcriptional complex that integrates DNA recognition with coactivator recruitment and nominate POU2F3-OCA-T as a structurally tractable vulnerability in tuft cell-like carcinomas.
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
Organizational Affiliation:
