ID   B2MG_XENLA              Reviewed;         115 AA.
AC   Q9IA97;
DT   30-MAY-2003, integrated into UniProtKB/Swiss-Prot.
DT   01-OCT-2000, sequence version 1.
DT   03-AUG-2022, entry version 92.
DE   RecName: Full=Beta-2-microglobulin;
DE   Flags: Precursor;
GN   Name=b2m;
OS   Xenopus laevis (African clawed frog).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Amphibia;
OC   Batrachia; Anura; Pipoidea; Pipidae; Xenopodinae; Xenopus; Xenopus.
OX   NCBI_TaxID=8355;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RA   Watson M.D., Minter R., Horton J.D.;
RL   Submitted (MAY-2000) to the EMBL/GenBank/DDBJ databases.
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}.
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DR   EMBL; AF217962; AAF37230.2; -; mRNA.
DR   RefSeq; NP_001082000.1; NM_001088531.1.
DR   PDB; 6A2B; X-ray; 2.80 A; B=20-113.
DR   PDBsum; 6A2B; -.
DR   AlphaFoldDB; Q9IA97; -.
DR   SMR; Q9IA97; -.
DR   GeneID; 398171; -.
DR   KEGG; xla:398171; -.
DR   CTD; 398171; -.
DR   Xenbase; XB-GENE-6251920; b2m.S.
DR   OrthoDB; 1556447at2759; -.
DR   Proteomes; UP000186698; Chromosome 9_10S.
DR   Bgee; 398171; Expressed in spleen and 19 other tissues.
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   CDD; cd05770; IgC_beta2m; 1.
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; 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.
PE   1: Evidence at protein level;
KW   3D-structure; Immunity; Immunoglobulin domain; MHC I; Reference proteome;
KW   Secreted; Signal.
FT   SIGNAL          1..16
FT                   /evidence="ECO:0000255"
FT   CHAIN           17..115
FT                   /note="Beta-2-microglobulin"
FT                   /id="PRO_0000018812"
FT   DOMAIN          22..113
FT                   /note="Ig-like C1-type"
FT   STRAND          24..31
FT                   /evidence="ECO:0007829|PDB:6A2B"
FT   STRAND          37..51
FT                   /evidence="ECO:0007829|PDB:6A2B"
FT   STRAND          53..59
FT                   /evidence="ECO:0007829|PDB:6A2B"
FT   STRAND          80..89
FT                   /evidence="ECO:0007829|PDB:6A2B"
FT   STRAND          96..102
FT                   /evidence="ECO:0007829|PDB:6A2B"
FT   STRAND          108..111
FT                   /evidence="ECO:0007829|PDB:6A2B"
SQ   SEQUENCE   115 AA;  13180 MW;  E72D36F1961DAA9E CRC64;
     MKIALVLLSL LALTLAESNI SPPVVKVYTA EPVDFGKTNE VICYVYNYHP PRLEMRLEKN
     GVEIPDCKQT DPSFQHNWKY YTTKSTHVHI DKGDKVECVV SHNGNPSKKY RLDIF