Soluble tapasin restores MHC class I expression and function in the tapasin-negative cell line .220.

@article{Lehner1998SolubleTR,
  title={Soluble tapasin restores MHC class I expression and function in the tapasin-negative cell line .220.},
  author={P. Lehner and M. Surman and P. Cresswell},
  journal={Immunity},
  year={1998},
  volume={8 2},
  pages={
          221-31
        }
}
Tapasin forms a bridge between TAP (transporters associated with antigen processing) and MHC class I molecules and plays a critical role in class I assembly. In its absence, TAP and class I do not associate, and class I cell surface expression is reduced. We now identify two independent functions for tapasin. Tapasin increases TAP levels and allows more peptide to be translocated to the endoplasmic reticulum. Furthermore, when expressed in the tapasin-negative .220 cell line, recombinant… Expand
Distinct Functions of Tapasin Revealed by Polymorphism in MHC Class I Peptide Loading1
TLDR
It is shown that, although constitutive levels of endogenous murine tapasin apparently are sufficient to form stable and long-lived complexes between the human HLA-B*4402 and mouse TAP proteins, this does not result in normal peptide loading and surface expression of B* 4402 molecules on mouse APC. Expand
A transmembrane tail: interaction of tapasin with TAP and the MHC class I molecule.
TLDR
Current understanding of functions involving the Tapasin TMD are summarized and it is proposed that, beyond stabilizing TAP, the tapasin T MD may also interact with the MHC class I heavy chain. Expand
The role of tapasin in MHC class I antigen assembly
TLDR
The discovery of tapasin has shed new light on the mechanisms of major histocompatibility complex class I assembly in the endoplasmic reticulum (ER), and it is suggested that tapasin may serve a peptide editing function. Expand
Tapasin Is Required for Efficient Peptide Binding to Transporter Associated with Antigen Processing*
  • Suling Li, K. Paulsson, Shangwu Chen, H. Sjögren, Ping Wang
  • Chemistry, Medicine
  • The Journal of Biological Chemistry
  • 2000
TLDR
It is concluded that tapasin is required for efficient peptide-TAP interaction and peptide transport across the membrane of the ER, and association of peptides with MHC class I molecules in the microsomes derived from tapasin mutant cell line 721.220 cells. Expand
Retention of empty MHC class I molecules by tapasin is essential to reconstitute antigen presentation in invertebrate cells
TLDR
Upon co‐expression of TAP, this retention/release function of tapasin was sufficient to reconstitute MHC class I antigen presentation in insect cells, thus defining the minimal non‐housekeeping functions required for MHCclass I antigen Presentation. Expand
The N‐terminal region of tapasin is required to stabilize the MHC class I loading complex
TLDR
Michaelis‐Menten analysis of peptide transport shows that this interaction between tapasin and TAP is sufficient to increase TAP levels without significantly affecting the intrinsic translocation rate. Expand
Tapasin Increases Efficiency of MHC I Assembly in the Endoplasmic Reticulum but Does Not Affect MHC I Stability at the Cell Surface1
TLDR
It is proposed that tapasin acts primarily to increase efficiency of assembly of MHC I within the ER, although stability of ER resident M HC I is decreased in tapasin-negative cells. Expand
Tapasin-related protein TAPBPR is an additional component of the MHC class I presentation pathway
TLDR
The identification of TAPBPR as an additional component of the M HC class I antigen-presentation pathway demonstrates that mechanisms controlling MHC class I expression remain incompletely understood. Expand
Assembly of tapasin-associated MHC class I in the absence of the transporter associated with antigen processing (TAP).
TLDR
Results demonstrate that regulation of the assembly of tapasin-associated MHC class I is independent of the interaction of Tapasin with TAP, but is dependent upon the peptides transported by TAP. Expand
Interaction of murine MHC class I molecules with tapasin and TAP enhances peptide loading and involves the heavy chain alpha3 domain.
TLDR
It is shown that tapasin is present in murine TAP-class I complexes as well and it is demonstrated that a mutant H-2Dd molecule that does not interact with TAP due to a Glu to Lys mutation at residue 222 of the H chain (Dd(E222K)) also fails to bind to tapasin, supporting the view that Tapasin bridges the association between class I and TAP. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 47 REFERENCES
A critical role for tapasin in the assembly and function of multimeric MHC class I-TAP complexes.
TLDR
The molecular cloning of tapasin revealed it to be a transmembrane glycoprotein encoded by an MHC-linked gene, a member of the immunoglobulin superfamily with a probable cytoplasmic endoplasmic reticulum retention signal. Expand
Regulation of MHC class I heterodimer stability and interaction with TAP by tapasin
TLDR
Evidence is obtained co-localizing the genetic defect of mutant 220 cells and the structural or a regulatory gene controlling the expression of tapasin on the short arm of chromosome 6, which includes the MHC, which implicate tapasin in a mechanism that promotes peptide binding by class I heterodimers through their interaction with TAP. Expand
Roles for calreticulin and a novel glycoprotein, tapasin, in the interaction of MHC class I molecules with TAP.
TLDR
It is shown that the related chaperone, calreticulin, binds human class I-beta 2m dimers prior to peptide loading, suggesting that calretiulin remains associated with at least a subset of class I molecules when they, in turn, bind to TAP. Expand
Allele-specific differences in the interaction of MHC class I molecules with transporters associated with antigen processing.
TLDR
Binding of peptides to two different pools of class I heterodimers may ensure efficient peptide association in an environment where peptides have a short life span. Expand
MHC class l/β2-microglobulin complexes associate with TAP transporters before peptide binding
TLDR
The results suggest that calnexin mediates class I/β2m dimerization, and subsequent binding of the dimers to TAP molecules facilitates their association with TAP-transported peptides. Expand
A viral ER-resident glycoprotein inactivates the MHC-encoded peptide transporter.
TLDR
A new mechanism for viral immune escape and a novel role for ER-resident proteins to regulate TAP via its luminal face are established. Expand
Interaction of MHC class I molecules with the transporter associated with antigen processing.
TLDR
The transporter associated with antigen processing (TAP) delivers cytosolic peptides into the endoplasmic reticulum (ER) where they bind to nascent class 1 histocompatibility molecules, and an association between the transporter and diverse class 1 products is revealed. Expand
Dependence of Peptide Binding by MHC Class I Molecules on Their Interaction with TAP
TLDR
A genetic defect in a human mutant cell line causes the complete failure of diverse class I heterodimers to associate with TAP and results from loss of function of an unidentified gene or genes linked to the MHC. Expand
Supply and transport of peptides presented by class I MHC molecules.
  • J. Howard
  • Biology, Medicine
  • Current opinion in immunology
  • 1995
TLDR
This conclusion puts in question the significance for class I loading of proteolytic processing and peptide generation in the endoplasmic reticulum. Expand
TAP associates with a unique class I conformation, whereas calnexin associates with multiple class I forms in mouse and man.
TLDR
Open forms of Ld are uniquely and specifically associated with TAP and that the conformational change in the class I H chain coincident with peptide binding induces TAP release, and a model for the sequential assembly of class I heterotrimers and their respective interactions with T AP and calnexin is proposed. Expand
...
1
2
3
4
5
...