Intramembrane proteolysis of signal peptides: an essential step in the generation of HLA-E epitopes. |
| |
| Authors: | M K Lemberg F A Bland A Weihofen V M Braud B Martoglio |
| |
| Affiliation: | Institute of Biochemistry, Swiss Federal Institute of Technology (Eidgen?ssiche Technische Hochschule), Zurich, Switzerland. |
| |
| Abstract: | Signal sequences of human MHC class I molecules are a unique source of epitopes for newly synthesized nonclassical HLA-E molecules. Binding of such conserved peptides to HLA-E induces its cell surface expression and protects cells from NK cell attack. After cleavage from the pre-protein, we show that the liberated MHC class I signal peptide is further processed by signal peptide peptidase in the hydrophobic, membrane-spanning region. This cut is essential for the release of the HLA-E epitope-containing fragment from the lipid bilayer and its subsequent transport into the lumen of the endoplasmic reticulum via the TAP. |
| |
| Keywords: | |
|
|
