Open AccessDirect observation of disordered regions in the major histocompatibility complex class II-associated invariant chain.
Author(s) -
Alan Jasanoff,
SeongJoon Park,
Don C. Wiley
Publication year - 1995
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.92.21.9900
Subject(s) - cd74 , major histocompatibility complex , peptide , mhc class i , ectodomain , mhc class ii , endoplasmic reticulum , antigen presentation , chemistry , microbiology and biotechnology , human leukocyte antigen , antigen , biology , biochemistry , cytotoxic t cell , genetics , in vitro , receptor
Invariant chain (Ii) is a trimeric membrane protein which binds and stabilizes major histocompatibility complex class II heterodimers in the endoplasmic reticulum and lysosomal compartments of antigen-presenting cells. In concert with an intracellular class II-like molecule, HLA-DM, Ii seems to facilitate loading of conventional class II molecules with peptides before transport of the class II-peptide complex to the cell surface for recognition by T cells. The interaction of Ii with class II molecules is thought to be mediated in large part through a region of 24 amino acids (the class II-associated Ii peptide, CLIP) which binds as a cleaved moiety in the antigenic peptide-binding groove of class II molecules in HLA-DM-deficient cell lines. Here we use nuclear magnetic resonance techniques to demonstrate that a soluble recombinant Ii ectodomain contains significant disordered regions which probably include CLIP.