|
|
||||||||
The Journal of Immunology, Vol 157, Issue 12 5487-5495, Copyright © 1996 by American Association of Immunologists
ARTICLES |
PH Schafer, JM Green, S Malapati, L Gu and SK Pierce
Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, IL 60208, USA.
HLA-DM has been shown in vitro to catalyze the release of invariant chain (Ii) derived peptides from the peptide-binding groove of class II molecules, thereby facilitating the binding of antigenic peptides. Previous studies showed that at steady state, the majority of DM resides in the class II peptide-loading compartment (IIPLC) where Ii dissociates from class II molecules and antigenic peptides are bound. Here we characterize the expression of DM in vivo in subcellular fractions containing the IIPLC. Using quantitative immunoblotting, we show that in the cell as a whole, class II molecules are expressed in 23-fold molar excess of DM. However, DM is concentrated in the IIPLC, where it is present in a considerably higher concentration relative to the class II molecules, in a molar ratio of 5DR:1 DM. This molar ratio of DM to DR in the IIPLC in vivo is consistent with the catalytic function proposed for DM from studies in vitro. We also provide both biochemical and genetic evidence that DM associates with complexes which contain Ii fragments and class II molecules in the IIPLC. Such complexes are only observed in leupeptin-treated cells in which Ii fails to be completely degraded and complexes containing the leupeptin- induced fragment of Ii (LIP) and class II molecules accumulate in the IIPLC. This observation is consistent with LIP-class II complexes being a substrate for DM in vivo and suggests that interactions of DM and LIP- class II are extremely transient under normal conditions.
This article has been cited by other articles:
![]() |
L.-E. Fallang, S. Roh, A. Holm, E. Bergseng, T. Yoon, B. Fleckenstein, A. Bandyopadhyay, E. D. Mellins, and L. M. Sollid Complexes of Two Cohorts of CLIP Peptides and HLA-DQ2 of the Autoimmune DR3-DQ2 Haplotype Are Poor Substrates for HLA-DM J. Immunol., October 15, 2008; 181(8): 5451 - 5461. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Neumann, A. Konig, and N. Koch Detection of aberrant association of DM with MHC class II subunits in the absence of invariant chain Int. Immunol., January 1, 2007; 19(1): 31 - 39. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. C. Doebele, A. Pashine, W. Liu, D. M. Zaller, M. Belmares, R. Busch, and E. D. Mellins Point Mutations in or Near the Antigen-Binding Groove of HLA-DR3 Implicate Class II-Associated Invariant Chain Peptide Affinity as a Constraint on MHC Class II Polymorphism J. Immunol., May 1, 2003; 170(9): 4683 - 4692. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Li, K. Siemasko, M. R. Clark, and W. Song Cooperative interaction of Ig{alpha} and Ig{beta} of the BCR regulates the kinetics and specificity of antigen targeting Int. Immunol., October 1, 2002; 14(10): 1179 - 1191. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A. Weber, C. T. Dao, J. Jun, J. L. Wigal, and P. E. Jensen Transmembrane Domain-Mediated Colocalization of HLA-DM and HLA-DR Is Required for Optimal HLA-DM Catalytic Activity J. Immunol., November 1, 2001; 167(9): 5167 - 5174. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. van Lith, M. van Ham, A. Griekspoor, E. Tjin, D. Verwoerd, J. Calafat, H. Janssen, E. Reits, L. Pastoors, and J. Neefjes Regulation of MHC Class II Antigen Presentation by Sorting of Recycling HLA-DM/DO and Class II within the Multivesicular Body J. Immunol., July 15, 2001; 167(2): 884 - 892. [Abstract] [Full Text] [PDF] |
||||
![]() |
C.-L. Chou and S. Sadegh-Nasseri Hla-Dm Recognizes the Flexible Conformation of Major Histocompatibility Complex Class II J. Exp. Med., December 18, 2000; 192(12): 1697 - 1706. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Louis-Plence, S. Kerlan-Candon, J. Morel, B. Combe, J. Clot, V. Pinet, and J.-F. Eliaou The Down-Regulation of HLA-DM Gene Expression in Rheumatoid Arthritis Is Not Related to Their Promoter Polymorphism J. Immunol., November 1, 2000; 165(9): 4861 - 4869. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. C. Cheng, M. L. Dykstra, R. N. Mitchell, and S. K. Pierce A Role for Lipid Rafts in B Cell Antigen Receptor Signaling and Antigen Targeting J. Exp. Med., December 6, 1999; 190(11): 1549 - 1560. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. K. Brown, C. Li, P. C. Cheng, and W. Song Trafficking of the Igalpha /Igbeta Heterodimer with Membrane Ig and Bound Antigen to the Major Histocompatibility Complex Class II Peptide-loading Compartment J. Biol. Chem., April 16, 1999; 274(16): 11439 - 11446. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Antoine, T Lang, E Prina, N Courret, and R Hellio H-2M molecules, like MHC class II molecules, are targeted to parasitophorous vacuoles of Leishmania-infected macrophages and internalized by amastigotes of L. amazonensis and L. mexicana J. Cell Sci., January 8, 1999; 112(15): 2559 - 2570. [Abstract] [PDF] |
||||
![]() |
C. Hammond, L. K. Denzin, M. Pan, J. M. Griffith, H. J. Geuze, and P. Cresswell The Tetraspan Protein CD82 Is a Resident of MHC Class II Compartments Where It Associates with HLA-DR, -DM, and -DO Molecules J. Immunol., October 1, 1998; 161(7): 3282 - 3291. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. H. Schafer, S. Malapati, K. K. Hanfelt, and S. K. Pierce The Assembly and Stability of MHC Class II-({alpha}{beta})2 Superdimers J. Immunol., September 1, 1998; 161(5): 2307 - 2316. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. A. Chianese-Bullock, H. I. Russell, C. Moller, W. Gerhard, J. J. Monaco, and L. C. Eisenlohr Antigen Processing of Two H2-IEd-Restricted Epitopes Is Differentially Influenced by the Structural Changes in a Viral Glycoprotein J. Immunol., August 15, 1998; 161(4): 1599 - 1607. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. B. Guerra, R. Busch, R. C. Doebele, W. Liu, T. Sawada, W. W. Kwok, M.-d. Y. Chang, and E. D. Mellins Novel Glycosylation of HLA-DR{alpha} Disrupts Antigen Presentation Without Altering Endosomal Localization J. Immunol., May 1, 1998; 160(9): 4289 - 4297. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Busch, R. C. Doebele, E. von Scheven, J. Fahrni, and E. D. Mellins Aberrant Intermolecular Disulfide Bonding in a Mutant HLA-DM Molecule: Implications for Assembly, Maturation, and Function J. Immunol., January 15, 1998; 160(2): 734 - 743. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |