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Biotinylated Cell-penetrating Peptides to Study Intracellular Protein-protein Interactions
Published on: December 20, 2017
Peptide length and sequence specificity of the mouse TAP1/TAP2 translocator
T N Schumacher1, D V Kantesaria, M T Heemels
1Center for Cancer Research, Massachusetts Institute of Technology, Cambridge 02139.
The Journal of Experimental Medicine
|February 1, 1994
Summary
The transporter associated with antigen processing (TAP) selects peptides for the endoplasmic reticulum based on size and a hydrophobic C-terminal amino acid. This transporter also exhibits ATP-dependent peptide efflux, potentially ensuring high-affinity peptide loading onto MHC class I molecules.
Area of Science:
- Immunology
- Molecular Biology
- Protein Transport
Background:
- The transporter associated with antigen processing (TAP) is crucial for presenting peptides to major histocompatibility complex (MHC) class I molecules.
- TAP facilitates peptide transport into the endoplasmic reticulum lumen in an ATP-dependent manner.
Purpose of the Study:
- To investigate the peptide selection specificity of the mouse TAP translocator (H-2b haplotype).
- To characterize the ATP- and temperature-dependent peptide efflux mechanism of TAP.
Main Methods:
- Analysis of peptide binding and transport by the mouse TAP translocator.
- Investigating peptide efflux in the cytosolic direction.
Main Results:
- Mouse TAP selects peptides with a minimum size of nine residues.
- Hydrophobic C-terminal amino acids are a key specificity determinant for TAP peptide selection.
- TAP mediates ATP- and temperature-dependent peptide efflux from the lumen.
Conclusions:
- The specificity of TAP for peptide size and C-terminal hydrophobicity aligns with the requirements for MHC class I binding.
- TAP-mediated peptide efflux may regulate peptide supply to MHC class I, favoring high-affinity peptides.
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