Characterization of the alpha subunit of the IFN-alpha receptor. Evidence of N- and O-linked glycosylation and association with other surface proteins.

摘要: We studied the association of alpha subunit (IFN-alpha-receptor) to other receptor components in human H-929 and U-266 myeloma cell lines. Immunoprecipitation performed with IFNaR3 mAb showed that two proteins molecular masses 205 145 kDa are co-precipitated subunit. These complexes may not bind IFN-alpha as shown by studies using heterobifunctional cross-linking reagent Denny-Jaffe partial cleavage homobifunctional cross-linker dithio succinimidyl propionate. also provided evidence at least subunits mass 130 (alpha subunit) 110 (including 20 corresponding IFN-alpha) contribute formation IFN-alpha-receptor complex. To further characterize IFN-alpha-receptor, immunoprecipitates were sequentially treated N-glycanase, neuraminidase O-glycanase. is heavily glycosylated has a protein precursor 68 kDa. Binding for high low affinity binding sites 2. Affinity experiments under conditions suggest site formed complex containing subunit, whereas 110-kDa 2 conditions.