Gene Ontology annotation through association of InterPro records with GO terms
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Gene Ontology annotation based on curation of immunofluorescence data
Combined Automated Annotation using Multiple IEA Methods
Essential role of CD8 palmitoylation in CD8 coreceptor function.
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Palmitoylation of the CD8 beta tail partitions CD8 alpha-beta, but not CD8 alpha-alpha, into lipid rafts, where CD8 associates with and activates LCK.
"We demonstrate that CD8 is palmitoylated at the cytoplasmic tail of CD8beta and that this allows partitioning of CD8alphabeta, but not of CD8alphaalpha, in lipid rafts."
Calyculin A inhibits expression of CD8alpha but not CD4 in human peripheral blood T cells.
CD8beta endows CD8 with efficient coreceptor function by coupling T cell receptor/CD3 to raft-associated CD8/p56(lck) complexes.
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The CD8 beta cytoplasmic portion, mainly via palmitoylation, partitions CD8 into lipid rafts and couples CD8 to TCR/CD3, increasing TCR avidity for peptide-MHC.
"We find that the cytoplasmic portion of CD8beta, mainly due to its palmitoylation, mediates partitioning of CD8 in lipid rafts, where it efficiently associates with p56(lck)."
Influence of human CD8 on antigen recognition by T-cell receptor-transduced cells.
Structural basis of the CD8 alpha beta/MHC class I interaction: focused recognition orients CD8 beta to a T cell proximal position.
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In the mouse CD8 alpha-beta/H-2Dd structure, CD8 beta contributes about half of the buried interface with the MHC class I alpha3 domain and sits in the T cell membrane-proximal position.
"The CD8β subunit of CD8αβ contributes almost equally (49%) to the buried surface of the interface."
The cytoplasmic domain of CD8 beta regulates Lck kinase activation and CD8 T cell development.
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In mouse hybridomas and thymocytes, absence of CD8 beta or deletion of its cytoplasmic domain lowers CD8 alpha-associated LCK kinase activity, and the size of the reduction tracks the impairment of CD8 single-positive thymocyte development.
"Lack of CD8 beta expression or expression of a cytoplasmic domain-deleted CD8 beta resulted in a severalfold reduction in CD8 alpha-associated Lck kinase activity compared with that observed with cells expressing wild-type CD8 beta chain."
Structural and mutational analyses of a CD8alphabeta heterodimer and comparison with the CD8alphaalpha homodimer.
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Mouse CD8alpha-beta ectodomain structure; alanine mutations in CD8 beta CDR2 and CDR3 loops abolish coreceptor activity, while CDR1 mutations have no effect.
"mutations in CD8beta CDR2 and CDR3 loops abolish CD8alphabeta coreceptor activity"
The human CD8β M-4 isoform dominant in effector memory T cells has distinct cytoplasmic motifs that confer unique properties.
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Humans have four membrane CD8 beta splice variants (M-1 to M-4); M-1 predominates in naive and M-4 in effector memory T cells, and the M-4 tail has a leucine-based internalization motif.
"The M-1 isoform which is the equivalent of murine CD8β, is predominantly expressed in naïve T cells, whereas, the M-4 isoform is predominantly expressed in effector memory T cells."
Extracellular domains of CD8α and CD8ß subunits are sufficient for HLA class I restricted helper functions of TCR-engineered CD4(+) T cells.
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In human CD4 T cells transduced with HLA class I-restricted TCRs, CD8 alpha-beta (not CD8 alpha-alpha) is needed for optimal function, and the extracellular domains of both subunits suffice.
"We demonstrate that the co-transduced CD8αβ co-receptor in HLA-I-TCR transduced CD4(+) T-cells behaves as an adhesion molecule, since for optimal antigen-specific HLA class I restricted CD4(+) T-cell reactivity the extracellular domains of the CD8α and ß subunits are sufficient."
Molecular biology and function of CD4 and CD8.
A second subunit of CD8 is expressed in human T cells.
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Human CD8 beta is expressed on the surface of most CD8 alpha-positive thymocytes and blood lymphocytes, has splice variants differing in the cytoplasmic tail, and one variant lacks the transmembrane domain.
"About 90% of human CD8 alpha positive thymocytes and peripheral blood lymphocytes express CD8 beta at the cell surface."
The human Lyt-3 molecule requires CD8 for cell surface expression.
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Human CD8 beta needs CD8 alpha for efficient cell surface expression.
"Interestingly, the human Lyt-3 molecule cannot be expressed alone, but requires the human Lyt-2 homologue for efficient cell surface expression."
Zinc is essential for binding of p56(lck) to CD4 and CD8alpha.
Falcon deep research report for human CD8B
Formation of CD8:Nef:AP-2 Complex:v-ATPase Complex
Internalization of the CD8:Nef:AP-2 Complex:v-ATPase Complex
TCR complex interacts with peptide antigen-presenting MHC Class I