Evidence that transporters associated with antigen processing translocate a major histocompatibility complex class I-binding peptide into the endoplasmic reticulum in an ATP-dependent manner

M. J. Androlewicz, K. S. Anderson, P. Cresswell

Research output: Contribution to journalArticle

221 Scopus citations

Abstract

We have investigated the role of the putative peptide transporters associated with antigen processing (TAP) by using a permeabilized-cell system. The main objective was to determine whether these molecules, which bear homology to the ATP-binding cassette family of transporters, translocate antigenic peptides across the endoplasmic reticulum membrane for assembly with major histocompatibility complex (MHC) class I molecules and β2- microglobulin light chain. The pore-forming toxin streptolysin O was used to generate permeabilized cells, and peptide translocation was determined by measuring the amount of added radiolabeled peptide bound to endogenous class I molecules. No radiolabeled peptide was associated with MHC class I glycoproteins from unpermeabilized cells. We found that efficient peptide binding to MHC class I molecules in permeabilized cells is both transporter dependent and ATP dependent. In antigen-processing mutant cells lacking a functional transporter, uptake occurs only through a less-efficient transporter and ATP-independent pathway. In addition, short peptides (8-10 amino acids) known to bind MHC class I molecules compete efficiently with a radiolabeled peptide for TAP-dependent translocation, whereas longer peptides and a peptide derived from an endoplasmic reticulum signal sequence do not compete efficiently. This result indicates that the optimal substrates for TAP possess the characteristics of MHC-binding peptides.

Original languageEnglish (US)
Pages (from-to)9130-9134
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume90
Issue number19
DOIs
StatePublished - Oct 29 1993
Externally publishedYes

Keywords

  • peptide transport

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Evidence that transporters associated with antigen processing translocate a major histocompatibility complex class I-binding peptide into the endoplasmic reticulum in an ATP-dependent manner'. Together they form a unique fingerprint.

  • Cite this