Pyrin binds the PSTPIP1/CD2BP1 protein, defining familial Mediterranean fever and PAPA syndrome as disorders in the same pathway.
Pyrin, the familial Mediterranean fever protein, is found in association with the cytoskeleton in myeloid/monocytic cells and modulates IL-1beta processing, NF-kappaB activation, and apoptosis. These effects are mediated in part through cognate interactions with the adaptor protein ASC, which shares an N-terminal motif with pyrin. We sought additional upstream regulators of inflammation by using pyrin as the bait in yeast two-hybrid assays. We now show that proline serine threonine phosphatase-interacting protein [PSTPIP1, or CD2-binding protein 1 (CD2BP1)], a tyrosine-phosphorylated protein involved in cytoskeletal organization, also interacts with pyrin. Recently, PSTPIP1/CD2BP1 mutations were shown to cause the syndrome of pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA), a dominantly inherited autoinflammatory disorder mediated predominantly by granulocytes. Endogenous PSTPIP1/CD2BP1 and pyrin are coexpressed in monocytes and granulocytes and can be coimmunoprecipitated from THP-1 cells. The B box segment of pyrin was necessary and the B box/coiled-coil segment sufficient for this interaction, whereas the SH3 and coiled-coil domains of PSTPIP1/CD2BP1 were both necessary, but neither was sufficient, for pyrin binding. The Y344F PSTPIP1/CD2BP1 mutation, which blocks tyrosine phosphorylation, was associated with a marked reduction in pyrin binding in pervanadate-treated cells. PAPA-associated A230T and E250Q PSTPIP1/CD2BP1 mutations markedly increased pyrin binding as assayed by immunoprecipitation and, relative to WT, these mutants were hyperphosphorylated when coexpressed with c-Abl kinase. Consistent with the hypothesis that these mutations exert a dominant-negative effect on the previously reported activity of pyrin, we found increased IL-1beta production by peripheral blood leukocytes from a clinically active PAPA patient with the A230T PSTPIP1/CD2BP1 mutation and in cell lines transfected with both PAPA-associated mutants.
Genetics and Genomics Branch and Office of the Clinical Director, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, MD 20892, USA.
Nitza G
NG
Shoham
Michael
M
Centola
Elizabeth
E
Mansfield
Keith M
KM
Hull
Geryl
G
Wood
Carol A
CA
Wise
Daniel L
DL
Kastner
D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D002460:Cell Line; D003598:Cytoskeletal Proteins; D010505:Familial Mediterranean Fever / Q000235:genetics*; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D005982:Glutathione Transferase / Q000378:metabolism; D006098:Granulocytes / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D007249:Inflammation; D007375:Interleukin-1 / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008856:Microscopy, Fluorescence; D009000:Monocytes / Q000378:metabolism; D009154:Mutation; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D016315:Proto-Oncogene Proteins c-abl / Q000378:metabolism; D000071198:Pyrin; D013577:Syndrome; D014162:Transfection; D020798:Two-Hybrid System Techniques; D014443:Tyrosine / Q000378:metabolism; D018909:src Homology Domains
C082279:CDC15 protein; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D007375:Interleukin-1; C000604192:MEFV protein, human; D011506:Proteins; D000071198:Pyrin; D014443:Tyrosine; D005982:Glutathione Transferase; D016315:Proto-Oncogene Proteins c-abl; D019204:GTP-Binding Proteins