Thermal stability of MHC class I-β2-microglobulin peptide complexes in the endoplasmic reticulum is determined by the peptide occupancy of the transporter associated with antigen processing complex

B. A.L. Owen, L. R. Pease

Research output: Contribution to journalArticle

4 Scopus citations

Abstract

Once MHC class I heavy chain binds β2-microglobulin (β2m) within the endoplasmic reticulum, an assembly complex comprising the class I heterodimer, TAP, TAPasin, calreticulin, and possibly Erp57 is formed before the binding of high affinity peptide. TAP-dependent delivery of high affinity peptide to in vitro translated Kbβ2m complexes within microsomes (TAP+/TAPasin+) was studied to determine at which point peptide binding becomes resistant to thermal denaturation. It was determined that the thermal stability of Kb2m-peptide complexes depends on the timing of peptide binding to Kbβ2m relative to TAP binding high affinity peptide. Premature exposure of the TAP complex to high affinity peptide before its association with class I heavy chain results in Kbβ2m-peptide-TAP complexes that lose peptide upon exposure to elevated temperature after solubilization away from microsome-associated proteins. These findings suggest that the order in which class I heavy chain associates with endoplasmic reticulum-resident chaperones and peptide determines the stability of Kbβ2m-peptide complexes.

Original languageEnglish (US)
Pages (from-to)1740-1747
Number of pages8
JournalJournal of Immunology
Volume166
Issue number3
DOIs
StatePublished - Feb 1 2001

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Fingerprint Dive into the research topics of 'Thermal stability of MHC class I-β<sub>2</sub>-microglobulin peptide complexes in the endoplasmic reticulum is determined by the peptide occupancy of the transporter associated with antigen processing complex'. Together they form a unique fingerprint.

  • Cite this