A peptide from heat shock protein 60 is the dominant peptide bound to Qa-1 in the absence of the MHC class Ia leader sequence peptide Qdm.
The MHC class Ib molecule Qa-1 binds specifically and predominantly to a single 9-aa peptide (AMAPRTLLL) derived from the leader sequence of many MHC class Ia proteins. This peptide is referred to as Qdm. In this study, we report the isolation and sequencing of a heat shock protein 60-derived peptide (GMKFDRGYI) from Qa-1. This peptide is the dominant peptide bound to Qa-1 in the absence of Qdm. A Qa-1-restricted CTL clone recognizes this heat shock protein 60 peptide, further verifying that it binds to Qa-1 and a peptide from the homologous Salmonella typhimurium protein GroEL (GMQFDRGYL). These observations have implications for how Qa-1 can influence NK cell and T cell effector function via the TCR and CD94/NKG2 family members, and how this effect can change under conditions that cause the peptides bound to Qa-1 to change.
Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Adrian
A
Davies
Suzanne
S
Kalb
Bitao
B
Liang
Carla J
CJ
Aldrich
François A
FA
Lemonnier
Hong
H
Jiang
Robert
R
Cotter
Mark J
MJ
Soloski
D000818:Animals; D017951:Antigen Presentation; D002460:Cell Line; D018834:Chaperonin 60 / Q000276:immunology / Q000378:metabolism*; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D018984:Epitopes, T-Lymphocyte / Q000378:metabolism; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D016056:Immunodominant Epitopes / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009842:Oligopeptides / Q000276:immunology / Q000378:metabolism*; D010446:Peptide Fragments / Q000276:immunology / Q000378:metabolism*; D010455:Peptides / Q000276:immunology / Q000378:metabolism; D011485:Protein Binding / Q000276:immunology; D021382:Protein Sorting Signals; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000378:metabolism
D018834:Chaperonin 60; D018984:Epitopes, T-Lymphocyte; D015395:Histocompatibility Antigens Class I; D016056:Immunodominant Epitopes; D009842:Oligopeptides; D010446:Peptide Fragments; D010455:Peptides; D021382:Protein Sorting Signals; C032907:Q surface antigens; C090580:Qdm protein, mouse