1. Transcriptional reprogramming by mutated IRF4 in lymphoma.
- Author
-
Schleussner, Nikolai, Cauchy, Pierre, Franke, Vedran, Giefing, Maciej, Fornes, Oriol, Vankadari, Naveen, Assi, Salam A., Costanza, Mariantonia, Weniger, Marc A., Akalin, Altuna, Anagnostopoulos, Ioannis, Bukur, Thomas, Casarotto, Marco G., Damm, Frederik, Daumke, Oliver, Edginton-White, Benjamin, Gebhardt, J. Christof M., Grau, Michael, Grunwald, Stephan, and Hansmann, Martin-Leo
- Subjects
INTERFERON regulatory factors ,HODGKIN'S disease ,MISSENSE mutation ,GENETIC regulation ,TRANSCRIPTION factors - Abstract
Disease-causing mutations in genes encoding transcription factors (TFs) can affect TF interactions with their cognate DNA-binding motifs. Whether and how TF mutations impact upon the binding to TF composite elements (CE) and the interaction with other TFs is unclear. Here, we report a distinct mechanism of TF alteration in human lymphomas with perturbed B cell identity, in particular classic Hodgkin lymphoma. It is caused by a recurrent somatic missense mutation c.295 T > C (p.Cys99Arg; p.C99R) targeting the center of the DNA-binding domain of Interferon Regulatory Factor 4 (IRF4), a key TF in immune cells. IRF4-C99R fundamentally alters IRF4 DNA-binding, with loss-of-binding to canonical IRF motifs and neomorphic gain-of-binding to canonical and non-canonical IRF CEs. IRF4-C99R thoroughly modifies IRF4 function by blocking IRF4-dependent plasma cell induction, and up-regulates disease-specific genes in a non-canonical Activator Protein-1 (AP-1)-IRF-CE (AICE)-dependent manner. Our data explain how a single mutation causes a complex switch of TF specificity and gene regulation and open the perspective to specifically block the neomorphic DNA-binding activities of a mutant TF. Cancer is often associated with mutant transcription factors (TFs) but their functional characterization is challenging. Here, the authors describe a recurrent mutation within TF IRF4 in human lymphomas and they show how it causes a complex switch in TF specificity and functionality. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF