NLRP3 tyrosine phosphorylation is controlled by protein tyrosine phosphatase PTPN22
Marianne R. Spalinger, … , Gerhard Rogler, Michael Scharl
Marianne R. Spalinger, … , Gerhard Rogler, Michael Scharl
Published May 2, 2016; First published April 4, 2016
Citation Information: J Clin Invest. 2016;126(5):1783-1800. https://doi.org/10.1172/JCI83669.
View: Text | PDF | Corrigendum
Research Article Gastroenterology Immunology

NLRP3 tyrosine phosphorylation is controlled by protein tyrosine phosphatase PTPN22

Abstract

Inflammasomes form as the result of the intracellular presence of danger-associated molecular patterns and mediate the release of active IL-1β, which influences a variety of inflammatory responses. Excessive inflammasome activation results in severe inflammatory conditions, but physiological IL-1β secretion is necessary for intestinal homeostasis. Here, we have described a mechanism of NLRP3 inflammasome regulation by tyrosine phosphorylation of NLRP3 at Tyr861. We demonstrated that protein tyrosine phosphatase non-receptor 22 (PTPN22), variants in which are associated with chronic inflammatory disorders, dephosphorylates NLRP3 upon inflammasome induction, allowing efficient NLRP3 activation and subsequent IL-1β release. In murine models, PTPN22 deficiency resulted in pronounced colitis, increased NLRP3 phosphorylation, but reduced levels of mature IL-1β. Conversely, patients with inflammatory bowel disease (IBD) that carried an autoimmunity-associated PTPN22 variant had increased IL-1β levels. Together, our results identify tyrosine phosphorylation as an important regulatory mechanism for NLRP3 that prevents aberrant inflammasome activation.

Authors

Marianne R. Spalinger, Stephanie Kasper, Claudia Gottier, Silvia Lang, Kirstin Atrott, Stephan R. Vavricka, Sylvie Scharl, Petrus M. Gutte, Markus G. Grütter, Hans-Dietmar Beer, Emmanuel Contassot, Andrew C. Chan, Xuezhi Dai, David J. Rawlings, Florian Mair, Burkhard Becher, Werner Falk, Michael Fried, Gerhard Rogler, Michael Scharl

×

Figure 5

NLRP3 is tyrosine phosphorylated.

Options: View larger image (or click on image) Download as PowerPoint
NLRP3 is tyrosine phosphorylated. THP-1 and MM6 cells (A and C), BMDCs (...
THP-1 and MM6 cells (A and C), BMDCs (B), and PBMCs (D) were treated with upLPS for 12 hours prior to activation with MDP (100 ng/ml, 24 hours), MSU (100 ng/ml, 6 hours), TiO2 (150 ng/ml, 24 hours), SiO2 (150 ng/ml, 24 hours), ATP (2 mM, 30 minutes), dsDNA, or flagellin, as indicated. NLRP3 was precipitated from cell lysates, and precipitates were analyzed for tyrosine phosphorylation, coprecipitated PTPN22, or coprecipitated PTPN2. (D) PTPN22 was precipitated in addition to NLRP3 and analyzed for coprecipitated NLRP3. (E) Amounts of NLRP3 and pTyr in NLRP3 precipitates were quantified using standard curves for NLRP3 and a pTyr peptide. The graph below the representative Western blots shows statistical analysis of densitometry. ND, not detected. Left and right blots in E were run on the same gel, but were discontinuous. Numbers below the blots in D show the amount of loaded NLRP3 or pTyr peptide (left) and measured amounts (right), respectively. The pound symbol (#) marks blots where the 130-kDa and 120-kDa forms of NLRP3 are not completely separated and appear as single bands. Data shown are from 1 of 3–5 independent experiments. *P < 0.05, **P < 0.01, Student’s t test with Bonferroni correction.