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Assaying peptide translocation by the peptide transporter TAP

Marlieke L M Jongsma1, Jacques Neefjes2

  • 1Department of Cell Biology II, The Netherlands Cancer Institute, Amsterdam, The Netherlands.

Methods in Molecular Biology (Clifton, N.J.)
|January 19, 2013
PubMed

MHC class I molecules display peptides at the cell surface that are mostly derived from cytosolic or nuclear proteins. Since peptide loading of MHC class I molecules occurs in the ER lumen, cytosolic peptides have to pass the ER membrane. The peptide transporter TAP translocates peptides over this ER membrane which is critical for successful MHC class I antigen presentation. How peptide translocation by TAP can be assayed and inhibitors of chemical or viral origin can be identified, will be described here.

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