Fig 2: CMTM4 is specifically associated with IL-17RC.a, b, Flow cytometry analysis of ST2 cells incubated with the indicated concentration of SF-IL-17A. Ligand binding was detected by Flag-APC antibody (a). Relative SF-IL-17A binding to ST2 cells was calculated from three independent experiments, mean ± s.e.m. (b). c, Immunoblotting analysis of lysates of wild-type ST2 cells that were stimulated with indicated concentrations of SF-IL-17A or commercial IL-17A (R&D Systems) for 15 min. d, Immunoblotting analysis of samples isolated through Flag immunoprecipitation from lysates of ST2 cells expressing SF-IL-17RB, SF-IL-17RD, or SF-IL-17RE. e, Comparison between murine and human IL-17RA and IL-17RC transmembrane domains. f, Flow cytometry analysis of surface expression of SF-IL-17RCWT and SF-IL-17RCTmRA ectopically expressed in ST2 cells. Mean + s.e.m. from six independent experiments. Two-tailed Mann–Whitney test. n.s. not significant. MFI, median fluorescence intensity. Data are representative of three (a–d) independent experiments. Source data

Fig 3: CMTM4 regulates IL-17RC plasma membrane localization.a, b, Immunoblotting analysis of CMTM4 and actin and flow cytometry analysis of IL-17RC surface expression in wild-type or several Cmtm4-/- ST2 cell lines (a) or Cmtm4-/- ST2 cell line #4 transduced with the expression vector coding for Myc-CMTM4 or EV (b). c, Real-time quantitative PCR analysis of the relative level of Cmtm4 transcript in wild-type and four Cmtm4-/- ST2 cell lines. Mean + s.e.m. from five independent experiments. Two-tailed Mann–Whitney test. d, Flow cytometry analysis of IL-17RA, IL-17RD, or TNFR1 surface expression in wild-type and Cmtm4-/- ST2 cells. e, Immunoblotting of IL-17RC, CMTM4, and actin, and flow cytometry analysis of IL-17RC surface expression in wild-type and Cmtm4-/- ST2 cells expressing IL-17RCTmRA. f-h, Immunoblotting analysis of CMTM4 and actin and flow cytometry analysis of IL-17RC and IL-17RA surface expression in wild-type or CMTM4-/- HeLa cells (f), CMTM4-/- HeLa transduced with the expression vector coding for Myc-CMTM4 or EV (g), and A549 wild-type, CMTM4-/- or control cell lines where CRISPR/Cas9 transfection did not cause CMTM4 deficiency (h). *, unspecific band. Flow cytometry data are based on five (e, f), four (d) or three (a, b, d, g, h) independent experiments. Mean + s.e.m., two-tailed unpaired t-test. n.s. not significant. MFI, median fluorescence intensity. Source data

Fig 4: CMTM4 mediates IL-17RC glycosylation.a, Immunoblotting analysis of samples isolated via immunoprecipitation with IL-17RC antibody or control isotype antibody from lysates of wild-type or Cmtm4-/- ST2 cells. b,c, Immunoblotting analysis of samples isolated via immunoprecipitation with IL-17RC antibody from lysates of wild-type or several Cmtm4-/- ST2 cell lines (b) or Cmtm4-/- ST2 cells expressing Myc-CMTM4 or EV (c). d, Immunoblotting analysis of samples isolated via immunoprecipitation with IL-17RC antibody from lysates of wild-type or Cmtm4-/- ST2 cells treated or not with proteasome inhibitor bortezomib (10 nM) for 24 h. e, Immunoblotting analysis of samples isolated by Flag immunoprecipitation from lysates of Cmtm4-/- ST2 cells transduced with expression vectors coding for indicated Myc-tagged members of CMTM family together with the expression vector coding for SF-IL-17RC. f-j, Immunoblotting analysis of samples isolated by Flag immunoprecipitation from lysates of wild-type or Cmtm4-/- ST2 cells expressing SF-IL-17RA (f), SF-IL-17RB (g), SF-IL-17RD (h), SF-IL-17RE (i), or SF-TNFR1 (j) and treated or not with PNGase F. *, unspecific band. Data are representative of four (a), three (b–d), or two (e–j) independent experiments. Source data