Fig. 1.

Model depicting the maturation pathway of Hp 2-1 oligomers. At the transcription level, the two Hp alleles lead to two distinctive mRNAs and thus two protein backbones. Initial glycosylation and oligomer formation occur in the ER, generating disulfide-bound oligomers. Furthermore, the glycans are maturing in the Golgi. Posttranslational elimination of Arg102/161 occurs in plasma. Eventually, the final mixture of mature oligomeric Hp assemblies is ready to capture Hb. See also SI Appendix, Fig. S1 for annotated amino acid sequences originating from the distinct allotypes Hp1 and Hp2.