CD8B_RAT
ID CD8B_RAT Reviewed; 208 AA.
AC P05541;
DT 01-NOV-1988, integrated into UniProtKB/Swiss-Prot.
DT 01-NOV-1988, sequence version 1.
DT 25-MAY-2022, entry version 142.
DE RecName: Full=T-cell surface glycoprotein CD8 beta chain;
DE AltName: Full=CD8 antigen 37 kDa chain;
DE AltName: Full=OX-8 membrane antigen;
DE AltName: CD_antigen=CD8b;
DE Flags: Precursor;
GN Name=Cd8b; Synonyms=Cd8b1;
OS Rattus norvegicus (Rat).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Euarchontoglires; Glires; Rodentia; Myomorpha; Muroidea; Muridae;
OC Murinae; Rattus.
OX NCBI_TaxID=10116;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC STRAIN=Sprague-Dawley; TISSUE=Thymocyte;
RX PubMed=3092111; DOI=10.1038/323074a0;
RA Johnson P., Williams A.F.;
RT "Striking similarities between antigen receptor J pieces and sequence in
RT the second chain of the murine CD8 antigen.";
RL Nature 323:74-76(1986).
CC -!- FUNCTION: Integral membrane glycoprotein that plays an essential role
CC in the immune response and serves multiple functions in responses
CC against both external and internal offenses. In T-cells, functions
CC primarily as a coreceptor for MHC class I molecule:peptide complex. The
CC antigens presented by class I peptides are derived from cytosolic
CC proteins while class II derived from extracellular proteins. Interacts
CC simultaneously with the T-cell receptor (TCR) and the MHC class I
CC proteins presented by antigen presenting cells (APCs). In turn,
CC recruits the Src kinase LCK to the vicinity of the TCR-CD3 complex. A
CC palmitoylation site in the cytoplasmic tail of CD8B chain contributes
CC to partitioning of CD8 into the plasma membrane lipid rafts where
CC signaling proteins are enriched. Once LCK recruited, it initiates
CC different intracellular signaling pathways by phosphorylating various
CC substrates ultimately leading to lymphokine production, motility,
CC adhesion and activation of cytotoxic T-lymphocytes (CTLs).
CC Additionally, plays a critical role in thymic selection of CD8+ T-
CC cells. {ECO:0000250|UniProtKB:P10300, ECO:0000250|UniProtKB:P10966}.
CC -!- SUBUNIT: Forms disulfide-linked heterodimers with CD8A at the cell
CC surface. Interacts with CD3D; this interaction couples TCR-CD3 with
CC CD8. Interacts with LCK. {ECO:0000250|UniProtKB:P10300,
CC ECO:0000250|UniProtKB:P10966}.
CC -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000250|UniProtKB:P10966};
CC Single-pass type I membrane protein {ECO:0000250|UniProtKB:P10966}.
CC Note=Requires the partner CD8A for efficient cell surface expression.
CC The heterodimer CD8A/CD8B localizes to lipid rafts due to CD8B
CC cytoplasmic tail palmitoylation. {ECO:0000250|UniProtKB:P10966}.
CC -!- PTM: Phosphorylated as a consequence of T-cell activation.
CC {ECO:0000250|UniProtKB:P10966}.
CC -!- PTM: Palmitoylated at the cytoplasmic tail and thereby targets the
CC heterodimer CD8A/CD8B to lipid rafts unlike CD8A homodimers.
CC {ECO:0000250|UniProtKB:P10966}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; X04310; CAA27850.1; -; mRNA.
DR PIR; A24184; A24184.
DR RefSeq; NP_113727.1; NM_031539.1.
DR AlphaFoldDB; P05541; -.
DR SMR; P05541; -.
DR STRING; 10116.ENSRNOP00000009392; -.
DR GlyGen; P05541; 3 sites.
DR PaxDb; P05541; -.
DR GeneID; 24931; -.
DR KEGG; rno:24931; -.
DR UCSC; RGD:2317; rat.
DR CTD; 926; -.
DR RGD; 2317; Cd8b.
DR eggNOG; ENOG502SANQ; Eukaryota.
DR InParanoid; P05541; -.
DR OrthoDB; 1377095at2759; -.
DR PhylomeDB; P05541; -.
DR Reactome; R-RNO-198933; Immunoregulatory interactions between a Lymphoid and a non-Lymphoid cell.
DR PRO; PR:P05541; -.
DR Proteomes; UP000002494; Unplaced.
DR GO; GO:0009986; C:cell surface; ISO:RGD.
DR GO; GO:0009897; C:external side of plasma membrane; ISO:RGD.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0005886; C:plasma membrane; ISO:RGD.
DR GO; GO:0043235; C:receptor complex; ISO:RGD.
DR GO; GO:0015026; F:coreceptor activity; IEA:InterPro.
DR GO; GO:0042288; F:MHC class I protein binding; IEA:InterPro.
DR GO; GO:0002250; P:adaptive immune response; IEA:UniProtKB-KW.
DR GO; GO:0042110; P:T cell activation; ISO:RGD.
DR GO; GO:0050852; P:T cell receptor signaling pathway; ISO:RGD.
DR Gene3D; 2.60.40.10; -; 1.
DR InterPro; IPR042414; CD8B.
DR InterPro; IPR007110; Ig-like_dom.
DR InterPro; IPR036179; Ig-like_dom_sf.
DR InterPro; IPR013783; Ig-like_fold.
DR InterPro; IPR003599; Ig_sub.
DR InterPro; IPR013106; Ig_V-set.
DR PANTHER; PTHR11292; PTHR11292; 1.
DR Pfam; PF07686; V-set; 1.
DR SMART; SM00409; IG; 1.
DR SMART; SM00406; IGv; 1.
DR SUPFAM; SSF48726; SSF48726; 1.
DR PROSITE; PS50835; IG_LIKE; 1.
PE 2: Evidence at transcript level;
KW Adaptive immunity; Cell membrane; Disulfide bond; Glycoprotein; Immunity;
KW Immunoglobulin domain; Lipoprotein; Membrane; Palmitate;
KW Reference proteome; Signal; Transmembrane; Transmembrane helix.
FT SIGNAL 1..21
FT CHAIN 22..208
FT /note="T-cell surface glycoprotein CD8 beta chain"
FT /id="PRO_0000014646"
FT TOPO_DOM 22..168
FT /note="Extracellular"
FT /evidence="ECO:0000255"
FT TRANSMEM 169..189
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 190..208
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT DOMAIN 22..131
FT /note="Ig-like V-type"
FT CARBOHYD 34
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 88
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT CARBOHYD 94
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000255"
FT DISULFID 41..115
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00114"
FT VARIANT 201
FT /note="H -> R"
SQ SEQUENCE 208 AA; 23400 MW; 1A2DA164DFA1B1F2 CRC64;
MQPWLWLVFS VKLSALWGSS ALLQTPSSLL VQTNQTAKMS CEAKTFPKGT TIYWLRELQD
SNKNKHFEFL ASRTSTKGIK YGERVKKNMT LSFNSTLPFL KIMDVKPEDS GFYFCAMVGS
PMVVFGTGTK LTVVDVLPTT APTKKTTLKK KQCPTPHPKT QKGLTCGLIT LSLLVACILV
LLVSLSVAIH FHCMRRRARI HFMKQFHK
