Stability of empty and peptide-loaded class II major histocompatibility complex molecules at neutral and endosomal pH: comparison to class I proteins.

The structure and thermal stability of empty and peptide-filled forms of the murine class II major histocompatibility complex (MHC) molecule I-E(k) were studied at neutral and mildly acidic pH. The two forms have distinct circular dichroic spectra, suggesting that a conformational change may accompa...

Бүрэн тодорхойлолт

Номзүйн дэлгэрэнгүй
Үндсэн зохиолчид: Reich, Z, Altman, J, Boniface, J, Lyons, D, Kozono, H, Ogg, G, Morgan, C, Davis, M
Формат: Journal article
Хэл сонгох:English
Хэвлэсэн: 1997
_version_ 1826272275995820032
author Reich, Z
Altman, J
Boniface, J
Lyons, D
Kozono, H
Ogg, G
Morgan, C
Davis, M
author_facet Reich, Z
Altman, J
Boniface, J
Lyons, D
Kozono, H
Ogg, G
Morgan, C
Davis, M
author_sort Reich, Z
collection OXFORD
description The structure and thermal stability of empty and peptide-filled forms of the murine class II major histocompatibility complex (MHC) molecule I-E(k) were studied at neutral and mildly acidic pH. The two forms have distinct circular dichroic spectra, suggesting that a conformational change may accompany peptide binding. Thermal stability profiles indicate that binding of peptide significantly increases the thermal stability of the empty heterodimers at both neutral and mildly acidic pH. Free energies calculated from these data provide a direct measure of this stabilization and show that the empty form of I-E(k) is significantly more stable than that of class I MHC proteins. Furthermore, for the two MHC class II proteins that were analyzed (I-E(k) and I-A(d)), thermal stability was not significantly altered by acidification. In contrast, of four class I MHC molecules studied, three have shown a significant loss in complex stability at low pH. The marked stability exhibited by their empty form, as well as their resistance to low pH, as observed in this study, correlate well with the ability of class II MHC molecules to traverse and bind peptides in acidic endosomal vesicles.
first_indexed 2024-03-06T22:09:59Z
format Journal article
id oxford-uuid:5179fc15-f78f-4d45-8da9-db17684e7ec7
institution University of Oxford
language English
last_indexed 2024-03-06T22:09:59Z
publishDate 1997
record_format dspace
spelling oxford-uuid:5179fc15-f78f-4d45-8da9-db17684e7ec72022-03-26T16:19:46ZStability of empty and peptide-loaded class II major histocompatibility complex molecules at neutral and endosomal pH: comparison to class I proteins.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:5179fc15-f78f-4d45-8da9-db17684e7ec7EnglishSymplectic Elements at Oxford1997Reich, ZAltman, JBoniface, JLyons, DKozono, HOgg, GMorgan, CDavis, MThe structure and thermal stability of empty and peptide-filled forms of the murine class II major histocompatibility complex (MHC) molecule I-E(k) were studied at neutral and mildly acidic pH. The two forms have distinct circular dichroic spectra, suggesting that a conformational change may accompany peptide binding. Thermal stability profiles indicate that binding of peptide significantly increases the thermal stability of the empty heterodimers at both neutral and mildly acidic pH. Free energies calculated from these data provide a direct measure of this stabilization and show that the empty form of I-E(k) is significantly more stable than that of class I MHC proteins. Furthermore, for the two MHC class II proteins that were analyzed (I-E(k) and I-A(d)), thermal stability was not significantly altered by acidification. In contrast, of four class I MHC molecules studied, three have shown a significant loss in complex stability at low pH. The marked stability exhibited by their empty form, as well as their resistance to low pH, as observed in this study, correlate well with the ability of class II MHC molecules to traverse and bind peptides in acidic endosomal vesicles.
spellingShingle Reich, Z
Altman, J
Boniface, J
Lyons, D
Kozono, H
Ogg, G
Morgan, C
Davis, M
Stability of empty and peptide-loaded class II major histocompatibility complex molecules at neutral and endosomal pH: comparison to class I proteins.
title Stability of empty and peptide-loaded class II major histocompatibility complex molecules at neutral and endosomal pH: comparison to class I proteins.
title_full Stability of empty and peptide-loaded class II major histocompatibility complex molecules at neutral and endosomal pH: comparison to class I proteins.
title_fullStr Stability of empty and peptide-loaded class II major histocompatibility complex molecules at neutral and endosomal pH: comparison to class I proteins.
title_full_unstemmed Stability of empty and peptide-loaded class II major histocompatibility complex molecules at neutral and endosomal pH: comparison to class I proteins.
title_short Stability of empty and peptide-loaded class II major histocompatibility complex molecules at neutral and endosomal pH: comparison to class I proteins.
title_sort stability of empty and peptide loaded class ii major histocompatibility complex molecules at neutral and endosomal ph comparison to class i proteins
work_keys_str_mv AT reichz stabilityofemptyandpeptideloadedclassiimajorhistocompatibilitycomplexmoleculesatneutralandendosomalphcomparisontoclassiproteins
AT altmanj stabilityofemptyandpeptideloadedclassiimajorhistocompatibilitycomplexmoleculesatneutralandendosomalphcomparisontoclassiproteins
AT bonifacej stabilityofemptyandpeptideloadedclassiimajorhistocompatibilitycomplexmoleculesatneutralandendosomalphcomparisontoclassiproteins
AT lyonsd stabilityofemptyandpeptideloadedclassiimajorhistocompatibilitycomplexmoleculesatneutralandendosomalphcomparisontoclassiproteins
AT kozonoh stabilityofemptyandpeptideloadedclassiimajorhistocompatibilitycomplexmoleculesatneutralandendosomalphcomparisontoclassiproteins
AT oggg stabilityofemptyandpeptideloadedclassiimajorhistocompatibilitycomplexmoleculesatneutralandendosomalphcomparisontoclassiproteins
AT morganc stabilityofemptyandpeptideloadedclassiimajorhistocompatibilitycomplexmoleculesatneutralandendosomalphcomparisontoclassiproteins
AT davism stabilityofemptyandpeptideloadedclassiimajorhistocompatibilitycomplexmoleculesatneutralandendosomalphcomparisontoclassiproteins