Disorder and T cell epitope for U1 snRNPA. (a) PONDR® plot of the U1 snRNPA protein (Swiss-Prot: P09012). The location of the strongly immunogenic peptide A3 (residues 44–56), which induces spreading and systemic autoimmune disease, is indicated by XXX. The weakly immunogenic peptide A6 (residues 103–115), which does not induce spreading or autoimmune disease , is indicated by xxx. (b) ProPred analysis of the U1 snRNPA protein in the context of MHC II. Only the results for alleles HLA-DRB_01, HLA-DRB_0102, HLA-DRB1_0301, and HLA-DRB_0305 are shown. The remaining 47 alleles show a very similar picture. The threshold is set at 3%. The black bar delimits the long disordered region of (a).