| Type: | Domain | Name: | MHC class II-associated invariant chain, trimerisation |
| Description: | This entry represents the trimerisation domain of the MHC class II-associated invariant chain (Ii). Ii plays a critical role in the assembly of the MHC, as well as in MHC II antigen processing by stabilising peptide-free class II alpha/beta heterodimers in a complex soon after their synthesis and directing transport of the complex from the endoplasmic reticulum to compartments where peptide loading of class II takes place []. In antigen-presenting cells (APCs), loading of MHC II molecules with peptides is regulated by Ii, which blocks MHC II antigen-binding sites in pre-endosomal compartments []. Several molecules then act upon MHC II molecules in endosomes to facilitate peptide loading: Ii-degrading proteases, the peptide exchange factor, human leukocyte antigen-DM (HLA-DM), and its modulator, HLA-DO (DO).The Invariant chain contains a single transmembrane domain. Ii first assembles into a trimer and then associates with three class II alpha/beta MHC heterodimers. Although the membrane-proximal region of the Ii luminal domain is structurally disordered, the C-terminal segment of the luminal domain is largely alpha-helical and contains a major interaction site for the Ii trimer []. | Short Name: | MHC_II-assoc_invariant_trimer |
| GO Term | Gene Name |
|---|---|
| GO:0042289 | IPR011988 |
| GO:0006886 | IPR011988 |
| GO:0006955 | IPR011988 |
| GO:0019882 | IPR011988 |
| GO:0016020 | IPR011988 |
| GO Term | Gene Name |
|---|---|
| GO:0042289 | IPR011988 |
| GO:0006886 | IPR011988 |
| GO:0006955 | IPR011988 |
| GO:0019882 | IPR011988 |
| GO:0016020 | IPR011988 |
