CD4_ERYPA
ID CD4_ERYPA Reviewed; 397 AA.
AC Q08339;
DT 01-FEB-1995, integrated into UniProtKB/Swiss-Prot.
DT 01-FEB-1995, sequence version 1.
DT 03-AUG-2022, entry version 101.
DE RecName: Full=T-cell surface glycoprotein CD4;
DE AltName: Full=T-cell surface antigen T4/Leu-3;
DE AltName: CD_antigen=CD4;
DE Flags: Fragment;
GN Name=CD4;
OS Erythrocebus patas (Red guenon) (Cercopithecus patas).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini;
OC Cercopithecidae; Cercopithecinae; Erythrocebus.
OX NCBI_TaxID=9538;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC TISSUE=Blood;
RX PubMed=1425921; DOI=10.1002/eji.1830221132;
RA Fomsgaard A., Hirsch V.M., Johnson P.R.;
RT "Cloning and sequences of primate CD4 molecules: diversity of the cellular
RT receptor for simian immunodeficiency virus/human immunodeficiency virus.";
RL Eur. J. Immunol. 22:2973-2981(1992).
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 II molecule:peptide complex.
CC The antigens presented by class II peptides are derived from
CC extracellular proteins while class I peptides are derived from
CC cytosolic proteins. Interacts simultaneously with the T-cell receptor
CC (TCR) and the MHC class II presented by antigen presenting cells
CC (APCs). In turn, recruits the Src kinase LCK to the vicinity of the
CC TCR-CD3 complex. LCK then initiates different intracellular signaling
CC pathways by phosphorylating various substrates ultimately leading to
CC lymphokine production, motility, adhesion and activation of T-helper
CC cells. In other cells such as macrophages or NK cells, plays a role in
CC differentiation/activation, cytokine expression and cell migration in a
CC TCR/LCK-independent pathway. Participates in the development of T-
CC helper cells in the thymus and triggers the differentiation of
CC monocytes into functional mature macrophages.
CC {ECO:0000250|UniProtKB:P01730}.
CC -!- SUBUNIT: Forms disulfide-linked homodimers at the cell surface.
CC Interacts with LCK. Interacts with PTK2/FAK1. Binds to P4HB/PDI.
CC Interacts with IL16; this interaction induces a CD4-dependent signaling
CC in lymphocytes. Interacts (via Ig-like V-type domain) with MHCII alpha
CC chain (via alpha-2 domain) and beta chain (via beta-2 domain); this
CC interaction increases the affinity of TCR for peptide-MHCII. CD4
CC oligomerization via Ig-like C2-type 2 and 3 domains appears to be
CC required for stable binding to MHCII and adhesion between T cells and
CC APCs. {ECO:0000250|UniProtKB:P01730}.
CC -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000250|UniProtKB:P01730};
CC Single-pass type I membrane protein {ECO:0000250|UniProtKB:P01730}.
CC Note=Localizes to lipid rafts. {ECO:0000250|UniProtKB:P01730}.
CC -!- DOMAIN: The Ig-like V-type domain mediates the interaction with MHCII.
CC {ECO:0000250|UniProtKB:P01730}.
CC -!- PTM: Palmitoylation and association with LCK contribute to the
CC enrichment of CD4 in lipid rafts. {ECO:0000250|UniProtKB:P01730}.
CC -!- PTM: Phosphorylated by PKC; phosphorylation plays an important role for
CC CD4 internalization. {ECO:0000250|UniProtKB:P01730}.
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; X73324; CAA51750.1; -; mRNA.
DR AlphaFoldDB; Q08339; -.
DR SMR; Q08339; -.
DR GO; GO:0009986; C:cell surface; IEA:UniProt.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0005886; C:plasma membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0015026; F:coreceptor activity; IEA:InterPro.
DR GO; GO:0023026; F:MHC class II protein complex binding; ISS:UniProtKB.
DR GO; GO:0002250; P:adaptive immune response; IEA:UniProtKB-KW.
DR GO; GO:0007155; P:cell adhesion; IEA:InterPro.
DR GO; GO:0030217; P:T cell differentiation; ISS:UniProtKB.
DR GO; GO:0045058; P:T cell selection; ISS:UniProtKB.
DR Gene3D; 2.60.40.10; -; 4.
DR InterPro; IPR000973; CD4.
DR InterPro; IPR015274; CD4-extracel.
DR InterPro; IPR007110; Ig-like_dom.
DR InterPro; IPR036179; Ig-like_dom_sf.
DR InterPro; IPR013783; Ig-like_fold.
DR InterPro; IPR008424; Ig_C2-set.
DR InterPro; IPR003599; Ig_sub.
DR InterPro; IPR003598; Ig_sub2.
DR InterPro; IPR013106; Ig_V-set.
DR InterPro; IPR013151; Immunoglobulin.
DR PANTHER; PTHR11422:SF0; PTHR11422:SF0; 1.
DR Pfam; PF05790; C2-set; 2.
DR Pfam; PF09191; CD4-extracel; 1.
DR Pfam; PF00047; ig; 1.
DR PRINTS; PR00692; CD4TCANTIGEN.
DR SMART; SM00409; IG; 3.
DR SMART; SM00408; IGc2; 2.
DR SMART; SM00406; IGv; 1.
DR SUPFAM; SSF48726; SSF48726; 4.
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; Repeat;
KW Transmembrane; Transmembrane helix.
FT CHAIN <1..>397
FT /note="T-cell surface glycoprotein CD4"
FT /id="PRO_0000072674"
FT TOPO_DOM <1..369
FT /note="Extracellular"
FT /evidence="ECO:0000255"
FT TRANSMEM 370..391
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TOPO_DOM 392..>397
FT /note="Cytoplasmic"
FT /evidence="ECO:0000255"
FT DOMAIN <1..98
FT /note="Ig-like V-type"
FT DOMAIN 99..176
FT /note="Ig-like C2-type 1"
FT DOMAIN 177..290
FT /note="Ig-like C2-type 2"
FT DOMAIN 291..347
FT /note="Ig-like C2-type 3"
FT LIPID 392
FT /note="S-palmitoyl cysteine"
FT /evidence="ECO:0000250"
FT LIPID 395
FT /note="S-palmitoyl cysteine"
FT /evidence="ECO:0000250"
FT CARBOHYD 269
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000250"
FT CARBOHYD 298
FT /note="N-linked (GlcNAc...) asparagine"
FT /evidence="ECO:0000250"
FT DISULFID 14..82
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00114"
FT DISULFID 128..157
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00114"
FT DISULFID 301..343
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00114"
FT NON_TER 1
FT NON_TER 397
SQ SEQUENCE 397 AA; 44081 MW; 67887397A6B7EA4F CRC64;
VVLGKKGDTV ELTCNASQKT TTQFHWKNSN QMKILGKQGS FLTKGPSKLR DRTDSRKSLW
DQGCFSMIIK NLKIEDSETY ICEVEDKKEE VELLVFGLTA NSDTHLLQGQ SLTLTLESPP
GSSPSVKCRS PRGKNIQGGR TLSVPQLERQ DSGTWTCTVS QDQNTVEFKI DIVVLAFQKA
SSTVYKKEGE QVEFSFPLAF TLEKLTGSGE LWWQAERASS SKSWITFDLK NKEVSVKRVT
QDPKLQMGEK LPLHLTLPQA LPHYAGSGNL TLALEAKTGK LHQEVNLVVM RATQFQENLT
CEVWGPTSPK LTLSLKLENK EATISKQAKA VWVLNPEEGM WQCLLSDSGQ VLLESNIKVL
PTWPTPVQPM ALIVLGGVAG LLLFTGLGIF FCVRCRH
