Kinetics of cytokine receptor trafficking determine signaling and functional selectivity

Autor: Jonathan Martinez-Fabregas, Stephan Wilmes, Luopin Wang, Maximillian Hafer, Elizabeth Pohler, Juliane Lokau, Christoph Garbers, Adeline Cozzani, Paul K Fyfe, Jacob Piehler, Majid Kazemian, Suman Mitra, Ignacio Moraga
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: eLife, Vol 8 (2019)
Druh dokumentu: article
ISSN: 2050-084X
DOI: 10.7554/eLife.49314
Popis: Cytokines activate signaling via assembly of cell surface receptors, but it is unclear whether modulation of cytokine-receptor binding parameters can modify biological outcomes. We have engineered IL-6 variants with different affinities to gp130 to investigate how cytokine receptor binding dwell-times influence functional selectivity. Engineered IL-6 variants showed a range of signaling amplitudes and induced biased signaling, with changes in receptor binding dwell-times affecting more profoundly STAT1 than STAT3 phosphorylation. We show that this differential signaling arises from defective translocation of ligand-gp130 complexes to the endosomal compartment and competitive STAT1/STAT3 binding to phospho-tyrosines in gp130, and results in unique patterns of STAT3 binding to chromatin. This leads to a graded gene expression response and differences in ex vivo differentiation of Th17, Th1 and Treg cells. These results provide a molecular understanding of signaling biased by cytokine receptors, and demonstrate that manipulation of signaling thresholds is a useful strategy to decouple cytokine functional pleiotropy.
Databáze: Directory of Open Access Journals