ID   CD4_SHEEP               Reviewed;          20 AA.
AC   P05542;
DT   01-NOV-1988, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1988, sequence version 1.
DT   25-MAY-2022, entry version 73.
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   Ovis aries (Sheep).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Laurasiatheria; Artiodactyla; Ruminantia; Pecora; Bovidae;
OC   Caprinae; Ovis.
OX   NCBI_TaxID=9940;
RN   [1]
RP   PROTEIN SEQUENCE.
RX   PubMed=3082751; DOI=10.1007/bf00377974;
RA   Classon B.J., Tsagaratos J., Kirszbaum L., Maddox J., McKay C.R.,
RA   Brandon M., McKenzie I.F.C., Walker I.D.;
RT   "The L3T4 antigen in mouse and the sheep equivalent are immunoglobulin-
RT   like.";
RL   Immunogenetics 23:129-132(1986).
CC   -!- FUNCTION: Accessory protein for MHC class-II antigen/T-cell receptor
CC       interaction. May regulate T-cell activation.
CC   -!- SUBUNIT: Associates with p56-LCK. Interacts with SPG21 (By similarity).
CC       {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Membrane; Single-pass type I membrane protein.
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DR   PIR; B47642; B47642.
DR   AlphaFoldDB; P05542; -.
DR   STRING; 9940.ENSOARP00000006749; -.
DR   eggNOG; ENOG502S0W5; Eukaryota.
DR   Proteomes; UP000002356; Unplaced.
DR   GO; GO:0016020; C:membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0002250; P:adaptive immune response; IEA:UniProtKB-KW.
DR   GO; GO:0030217; P:T cell differentiation; ISS:UniProtKB.
DR   GO; GO:0045058; P:T cell selection; ISS:UniProtKB.
PE   1: Evidence at protein level;
KW   Adaptive immunity; Direct protein sequencing; Immunity;
KW   Immunoglobulin domain; Membrane; Reference proteome.
FT   CHAIN           1..>20
FT                   /note="T-cell surface glycoprotein CD4"
FT                   /id="PRO_0000072675"
FT   NON_TER         20
SQ   SEQUENCE   20 AA;  1928 MW;  421F09570FEA97EE CRC64;
     KAVVLGKAGG TAELPCQASQ