Thyroglobulin type‐I‐like domains in invariant chain fusion proteins mediate resistance to cathepsin L digestion

FEBS Letters

Herzog, Volker²  Hitzel, Christoph¹  Koch, Norbert¹  Kummer, Markus P.²  Brix, Klaudia²  Kanzler, Holger¹  König, Angelika¹ 

[1] Division of Immunobiology, University of Bonn, Römerstraʕe 164, D-53117 Bonn, Germany;Institute of Cell Biology, University of Bonn, Bonn, Germany

关键词: MHC;    Invariant chain;    Cathepsin inhibitor;    Thyroglobulin;    MHCII;    major histocompatibility complex class II molecules;    Ii;    MHCII associated invariant chain;    Tg;    thyroglobulin;    TgR;    thyroglobulin repeat;    FCS;    fetal calf serum;    EGP;    epithelial glycoprotein;   

DOI  :  10.1016/S0014-5793(00)02189-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The MHCII associated invariant chain isoform Ii41 shows homology to a repeat in thyroglobulin (TgR). We show that the Ii31 isoform, which lacks the TgR-like domain, is sensitive to cathepsin L treatment whereas Ii41 displays substantial resistance. The TgR-like sequence of Ii41 was exchanged for thyroglobulin type-IA and -IB repeats, that contain six or four cysteine residues. Resistance to cathepsin L digestion was maintained upon substitution of the Ii41 TgR for homologous sequences from TgR type-IA. Mutation of a conserved cysteine in the TgR domain of an Ii fusion protein strongly reduced resistance to cathepsin L digestion.

【 授权许可】

Unknown