Selective degradation of T cell antigen receptor chains retained in a pre-Golgi compartment.

Chen, C; Bonifacino, Juan S.; Yuan, Lydia C.; Klausner, Richard D.

doi:10.1083/jcb.107.6.2149

Cited by 139 publications

(106 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, properly associated wild-type V ␣ V ␤ protein was not displayed at the cell surface. The eukaryotic secretory pathway retains and degrades misfolded proteins, as shown for the assembly of the TCR-CD3 complex (21). In yeast, secretion efficiency has been found to correlate with thermodynamic stability of a series of mutants of bovine pancreatic trypsin inhibitor (22).…”

Section: Resultsmentioning

confidence: 99%

Selection of functional T cell receptor mutants from a yeast surface-display library

Kieke

Shusta

Boder

et al. 1999

Proc. Natl. Acad. Sci. U.S.A.

160

128

View full text Add to dashboard Cite

The heterodimeric ␣␤ T cell receptor (TCR) for antigen is the key determinant of T cell specificity. The structure of the TCR is very similar to that of antibodies, but the engineering of TCRs by directed evolution with combinatorial display libraries has not been accomplished to date. Here, we report that yeast surface display of a TCR was achieved only after the mutation of specific variable region residues. These residues are located in two regions of the TCR, at the interface of the ␣-and ␤-chains and in the ␤-chain framework region that is thought to be in proximity to the CD3 signal-transduction complex. The mutations are encoded naturally in many antibody variable regions, indicating specific functional differences that have not been appreciated between TCRs and antibodies. The identification of these residues provides an explanation for the inherent difficulties in the display of wild-type TCRs compared with antibodies. Yeastdisplayed mutant TCRs bind specifically to the peptide͞MHC antigen, enabling engineering of soluble T cell receptors as specific T cell antagonists. This strategy of random mutagenesis followed by selection for surface expression may be of general use in the directed evolution of other eukaryotic proteins that are refractory to display.T cell receptors (TCRs) and antibodies have evolved to recognize different classes of ligands. Antibodies function as membrane-bound and soluble proteins that bind to soluble antigens, whereas TCRs function only as membrane-bound molecules that bind to cell-associated peptide͞MHC antigens. All of the energy of the antibody:antigen interaction focuses on the foreign antigen, whereas a substantial fraction of the energy of the TCR:peptide͞MHC interaction seems to be directed at the self-MHC molecule (1). In addition, antibodies can have ligand-binding affinities that are orders of magnitude higher than those of TCRs, largely because of the processes of somatic mutation and affinity maturation. In their normal cellular context, TCRs do not undergo somatic mutation and the processes of thymic selection seem to operate by maintaining a narrow window of affinities (2). The association of TCRs at the cell surface with the accessory molecules CD4 or CD8 also may influence the functional affinity of TCRs (3). Despite these differences, the three-dimensional structures of the two proteins are remarkably similar, with the hypervariable regions forming loops on a single face of the molecule that contacts the antigen (4-7).Based on their structural similarities, it is somewhat surprising that there have been significant differences in the success of producing soluble and surface-displayed forms of the extracellular domains of TCRs and antibodies in heterologous expression systems. Many antibodies have now been expressed at high yield and solubility as either intact or Fab-fragment forms or as single-chain (sc) fragment-variable (Fv) proteins. In addition, there are numerous antigen-binding Fv fragments that have been isolated de novo and͞or improved through...

show abstract

Section: Resultsmentioning

confidence: 99%

Selection of functional T cell receptor mutants from a yeast surface-display library

Kieke

Shusta

Boder

et al. 1999

Proc. Natl. Acad. Sci. U.S.A.

160

128

View full text Add to dashboard Cite

show abstract

“…Interference with the normal synthesis, degradation, transport, or processing of gene transcripts coding for the various TCR/CD3 chains would prohibit expression of the antigenreceptor complex (35,36). Mature (23)(24)(25)(26)(27)(28).…”

Section: Discussionmentioning

confidence: 99%

A specific defect in CD3 gamma-chain gene transcription results in loss of T-cell receptor/CD3 expression late after human immunodeficiency virus infection of a CD4+ T-cell line.

Willard-Gallo¹,

Keere²,

Kettmann³

1990

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Because the subunits may be synthesized at different rates and not necessarily in stoichiometric amount, there must be mechanisms to ensure that only properly assembled and stable complexes reach the cell surface (Rose and Doms, 1988;Hurtley and Helenius, 1989;Pelham, 1989). Studies on the assembly of multimeric proteins such as the T cell receptor (Lippincott-Schwartz et al, 1988;Chen et al, 1988), asialoglycoprotein receptor (Amara et al, 1989;Wikstrom and Lodish, 1993), acetylcholine receptors (Blount and Merlie, 1990), or immunoglobulins peptides are generated in the cytosol by an as yet incompletely defined mechanism (Arnold et al, 1992;Momburg et al, 1992;Howard and Seelig, 1993). Ubiquitinylation and proteolysis by proteasomes have been proposed as major candidates (Michalek et al, 1993;Dick et al, 1994;Rock et al, 1994).…”

mentioning

confidence: 99%

Misfolded major histocompatibility complex class I molecules accumulate in an expanded ER-Golgi intermediate compartment.

Raposo

Santen

Leijendekker

et al. 1995

The Journal of Cell Biology

127

View full text Add to dashboard Cite

Abstract. Misfolded membrane proteins are rapidly degraded, often shortly after their synthesis and insertion in the endoplasmic reticulum (ER), but the exact location and mechanisms of breakdown remain unclear. We have exploited the requirement of MHC class I molecules for peptide to achieve their correct conformation: peptide can be withheld by introducing a null mutation for the MHC-encoded peptide transporter, TAP. By withholding TAP-dependent peptides, the vast majority of newly synthesized class I molecules fails to leave the endoplasmic reticulum and is degraded. We used mice transgenic for HLA-B27 on a TAPl-deficient background to allow visualization by immunoelectron microscopy of misfolded HLA-B27 molecules in thymic epithelial cells. In such HLA transgenic animals, the TAP mutation can be considered a genetic switch that allows control over the extent of folding of the protein of interest, HLA-B27, while the rate of synthesis of the constituent subunits remains unaltered.,In TAPl-deficient, HLA-B27 transgenic animals, HLA-B27 molecules fail to assemble correctly, and do not undergo carbohydrate modifications associated with the Golgi apparatus, such as conversion to Endoglycosidase H resistance, and acquisition of sialic acids. We show that such molecules accumulate in an expanded network of tubular and fenestrated membranes. This compartment has its counterpart in normal thymic epithelial cells, and is identified as an ER-Golgi intermediate. We detect the presence of ubiquitin and ubiquitin-conjugating enzymes in association with this compartment, suggesting a nonlysosomal mode of degradation of its contents.

show abstract

Selective degradation of T cell antigen receptor chains retained in a pre-Golgi compartment.

Cited by 139 publications

References 72 publications

Selection of functional T cell receptor mutants from a yeast surface-display library

Selection of functional T cell receptor mutants from a yeast surface-display library

A specific defect in CD3 gamma-chain gene transcription results in loss of T-cell receptor/CD3 expression late after human immunodeficiency virus infection of a CD4+ T-cell line.

Misfolded major histocompatibility complex class I molecules accumulate in an expanded ER-Golgi intermediate compartment.

Contact Info

Product

Resources

About