ID   B2MG_TACAC              Reviewed;         118 AA.
AC   Q864T6;
DT   13-SEP-2005, integrated into UniProtKB/Swiss-Prot.
DT   01-JUN-2003, sequence version 1.
DT   25-MAY-2022, entry version 64.
DE   RecName: Full=Beta-2-microglobulin;
DE   Flags: Precursor;
GN   Name=B2M;
OS   Tachyglossus aculeatus aculeatus (Southeast Australian short-beaked
OS   echidna).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Monotremata; Tachyglossidae; Tachyglossus.
OX   NCBI_TaxID=49271;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RX   PubMed=12590975; DOI=10.1016/s0145-305x(02)00095-2;
RA   Miska K.B., Hellman L., Miller R.D.;
RT   "Characterization of beta(2)-microglobulin coding sequence from three non-
RT   placental mammals: the duckbill platypus, the short-beaked echidna, and the
RT   grey short-tailed opossum.";
RL   Dev. Comp. Immunol. 27:247-256(2003).
CC   -!- FUNCTION: Component of the class I major histocompatibility complex
CC       (MHC). Involved in the presentation of peptide antigens to the immune
CC       system (By similarity). {ECO:0000250}.
CC   -!- SUBUNIT: Heterodimer of an alpha chain and a beta chain. Beta-2-
CC       microglobulin is the beta-chain of major histocompatibility complex
CC       class I molecules (By similarity). {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250}.
CC   -!- SIMILARITY: Belongs to the beta-2-microglobulin family. {ECO:0000305}.
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; AY125949; AAM98338.1; -; mRNA.
DR   AlphaFoldDB; Q864T6; -.
DR   SMR; Q864T6; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0042612; C:MHC class I protein complex; IEA:UniProtKB-KW.
DR   GO; GO:0002474; P:antigen processing and presentation of peptide antigen via MHC class I; IEA:UniProtKB-KW.
DR   GO; GO:0006955; P:immune response; IEA:InterPro.
DR   Gene3D; 2.60.40.10; -; 1.
DR   InterPro; IPR015707; B2Microglobulin.
DR   InterPro; IPR007110; Ig-like_dom.
DR   InterPro; IPR036179; Ig-like_dom_sf.
DR   InterPro; IPR013783; Ig-like_fold.
DR   InterPro; IPR003006; Ig/MHC_CS.
DR   InterPro; IPR003597; Ig_C1-set.
DR   PANTHER; PTHR19944:SF62; PTHR19944:SF62; 1.
DR   Pfam; PF07654; C1-set; 1.
DR   SMART; SM00407; IGc1; 1.
DR   SUPFAM; SSF48726; SSF48726; 1.
DR   PROSITE; PS50835; IG_LIKE; 1.
DR   PROSITE; PS00290; IG_MHC; 1.
PE   3: Inferred from homology;
KW   Disulfide bond; Immunity; Immunoglobulin domain; MHC I; Secreted; Signal.
FT   SIGNAL          1..21
FT                   /evidence="ECO:0000255"
FT   CHAIN           22..118
FT                   /note="Beta-2-microglobulin"
FT                   /id="PRO_0000041828"
FT   DOMAIN          26..113
FT                   /note="Ig-like C1-type"
FT   DISULFID        46..101
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00114"
SQ   SEQUENCE   118 AA;  13586 MW;  C1EF44E34D90029C CRC64;
     MESRWGIVVI GLLCCVSWVE AITSSPKIQV YTRSPAENGK HNHLNCYVSS FHPPQITIRL
     LRNGEEMPNV ERSDLSFSND WTFHRLVHTG FVPNDKDVFE CEVTHNSVTK SVKWDRDN