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Entry version 160 (11 Dec 2019)
Sequence version 2 (01 Feb 1994)
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Protein

Beta-2-microglobulin

Gene

B2M

Organism
Bos taurus (Bovine)
Status
Reviewed-Annotation score:

Annotation score:4 out of 5

<p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
-Experimental evidence at protein leveli <p>This indicates the type of evidence that supports the existence of the protein. Note that the ‘protein existence’ evidence does not give information on the accuracy or correctness of the sequence(s) displayed.<p><a href='/help/protein_existence' target='_top'>More...</a></p>

<p>This section provides any useful information about the protein, mostly biological knowledge.<p><a href='/help/function_section' target='_top'>More...</a></p>Functioni

Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system.

<p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:<p><a href='/help/gene_ontology' target='_top'>More...</a></p>GO - Biological processi

<p>UniProtKB Keywords constitute a <a href="http://www.uniprot.org/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='/help/keywords' target='_top'>More...</a></p>Keywordsi

Biological processImmunity

Enzyme and pathway databases

Reactome - a knowledgebase of biological pathways and processes

More...
Reactomei
R-BTA-1236974 ER-Phagosome pathway
R-BTA-1236977 Endosomal/Vacuolar pathway
R-BTA-198933 Immunoregulatory interactions between a Lymphoid and a non-Lymphoid cell
R-BTA-2424491 DAP12 signaling
R-BTA-6798695 Neutrophil degranulation
R-BTA-983170 Antigen Presentation: Folding, assembly and peptide loading of class I MHC

<p>This section provides information about the protein and gene name(s) and synonym(s) and about the organism that is the source of the protein sequence.<p><a href='/help/names_and_taxonomy_section' target='_top'>More...</a></p>Names & Taxonomyi

<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section provides an exhaustive list of all names of the protein, from commonly used to obsolete, to allow unambiguous identification of a protein.<p><a href='/help/protein_names' target='_top'>More...</a></p>Protein namesi
Recommended name:
Beta-2-microglobulin
Alternative name(s):
Lactollin
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section indicates the name(s) of the gene(s) that code for the protein sequence(s) described in the entry. Four distinct tokens exist: ‘Name’, ‘Synonyms’, ‘Ordered locus names’ and ‘ORF names’.<p><a href='/help/gene_name' target='_top'>More...</a></p>Gene namesi
Name:B2M
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section provides information on the name(s) of the organism that is the source of the protein sequence.<p><a href='/help/organism-name' target='_top'>More...</a></p>OrganismiBos taurus (Bovine)
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section shows the unique identifier assigned by the NCBI to the source organism of the protein. This is known as the ‘taxonomic identifier’ or ‘taxid’.<p><a href='/help/taxonomic_identifier' target='_top'>More...</a></p>Taxonomic identifieri9913 [NCBI]
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section contains the taxonomic hierarchical classification lineage of the source organism. It lists the nodes as they appear top-down in the taxonomic tree, with the more general grouping listed first.<p><a href='/help/taxonomic_lineage' target='_top'>More...</a></p>Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaLaurasiatheriaArtiodactylaRuminantiaPecoraBovidaeBovinaeBos
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section is present for entries that are part of a <a href="http://www.uniprot.org/proteomes">proteome</a>, i.e. of a set of proteins thought to be expressed by organisms whose genomes have been completely sequenced.<p><a href='/help/proteomes_manual' target='_top'>More...</a></p>Proteomesi
  • UP000009136 <p>A UniProt <a href="http://www.uniprot.org/manual/proteomes_manual">proteome</a> can consist of several components. <br></br>The component name refers to the genomic component encoding a set of proteins.<p><a href='/help/proteome_component' target='_top'>More...</a></p> Componenti: Chromosome 10

<p>This section provides information on the location and the topology of the mature protein in the cell.<p><a href='/help/subcellular_location_section' target='_top'>More...</a></p>Subcellular locationi

Extracellular region or secreted Cytosol Plasma membrane Cytoskeleton Lysosome Endosome Peroxisome ER Golgi apparatus Nucleus Mitochondrion Manual annotation Automatic computational assertionGraphics by Christian Stolte & Seán O’Donoghue; Source: COMPARTMENTS

Keywords - Cellular componenti

MHC I, Secreted

<p>This section describes post-translational modifications (PTMs) and/or processing events.<p><a href='/help/ptm_processing_section' target='_top'>More...</a></p>PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the ‘PTM / Processing’ section denotes the presence of an N-terminal signal peptide.<p><a href='/help/signal' target='_top'>More...</a></p>Signal peptidei1 – 201 PublicationAdd BLAST20
<p>This subsection of the ‘PTM / Processing’ section describes the extent of a polypeptide chain in the mature protein following processing.<p><a href='/help/chain' target='_top'>More...</a></p>ChainiPRO_000001875621 – 118Beta-2-microglobulinAdd BLAST98

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the PTM / Processing":/help/ptm_processing_section section describes the positions of cysteine residues participating in disulfide bonds.<p><a href='/help/disulfid' target='_top'>More...</a></p>Disulfide bondi45 ↔ 99PROSITE-ProRule annotation1 Publication

Keywords - PTMi

Disulfide bond

Proteomic databases

PaxDb, a database of protein abundance averages across all three domains of life

More...
PaxDbi
P01888

PeptideAtlas

More...
PeptideAtlasi
P01888

PRoteomics IDEntifications database

More...
PRIDEi
P01888

PTM databases

CarbonylDB database of protein carbonylation sites

More...
CarbonylDBi
P01888

<p>This section provides information on the expression of a gene at the mRNA or protein level in cells or in tissues of multicellular organisms.<p><a href='/help/expression_section' target='_top'>More...</a></p>Expressioni

Gene expression databases

Bgee dataBase for Gene Expression Evolution

More...
Bgeei
ENSBTAG00000012330 Expressed in 10 organ(s), highest expression level in spleen

<p>This section provides information on the quaternary structure of a protein and on interaction(s) with other proteins or protein complexes.<p><a href='/help/interaction_section' target='_top'>More...</a></p>Interactioni

<p>This subsection of the <a href="http://www.uniprot.org/help/interaction_section">'Interaction'</a> section provides information about the protein quaternary structure and interaction(s) with other proteins or protein complexes (with the exception of physiological receptor-ligand interactions which are annotated in the <a href="http://www.uniprot.org/help/function_section">'Function'</a> section).<p><a href='/help/subunit_structure' target='_top'>More...</a></p>Subunit structurei

Heterodimer of an alpha chain and a beta chain. Beta-2-microglobulin is the beta-chain of major histocompatibility complex class I molecules.

1 Publication

Protein-protein interaction databases

STRING: functional protein association networks

More...
STRINGi
9913.ENSBTAP00000016359

<p>This section provides information on the tertiary and secondary structure of a protein.<p><a href='/help/structure_section' target='_top'>More...</a></p>Structurei

Secondary structure

1118
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details

3D structure databases

SWISS-MODEL Repository - a database of annotated 3D protein structure models

More...
SMRi
P01888

Database of comparative protein structure models

More...
ModBasei
Search...

Protein Data Bank in Europe - Knowledge Base

More...
PDBe-KBi
Search...

Miscellaneous databases

Relative evolutionary importance of amino acids within a protein sequence

More...
EvolutionaryTracei
P01888

<p>This section provides information on sequence similarities with other proteins and the domain(s) present in a protein.<p><a href='/help/family_and_domains_section' target='_top'>More...</a></p>Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the <a href="http://www.uniprot.org/help/family_and_domains_section">Family and Domains</a> section describes the position and type of a domain, which is defined as a specific combination of secondary structures organized into a characteristic three-dimensional structure or fold.<p><a href='/help/domain' target='_top'>More...</a></p>Domaini25 – 112Ig-like C1-typeAdd BLAST88

<p>This subsection of the ‘Family and domains’ section provides information about the sequence similarity with other proteins.<p><a href='/help/sequence_similarities' target='_top'>More...</a></p>Sequence similaritiesi

Belongs to the beta-2-microglobulin family.Curated

Keywords - Domaini

Immunoglobulin domain, Signal

Phylogenomic databases

evolutionary genealogy of genes: Non-supervised Orthologous Groups

More...
eggNOGi
ENOG410J15A Eukaryota
ENOG410YTDG LUCA

Ensembl GeneTree

More...
GeneTreei
ENSGT00690000102227

The HOGENOM Database of Homologous Genes from Fully Sequenced Organisms

More...
HOGENOMi
HOG000043084

InParanoid: Eukaryotic Ortholog Groups

More...
InParanoidi
P01888

KEGG Orthology (KO)

More...
KOi
K08055

Identification of Orthologs from Complete Genome Data

More...
OMAi
HTEFTPT

Database of Orthologous Groups

More...
OrthoDBi
1556447at2759

TreeFam database of animal gene trees

More...
TreeFami
TF334167

Family and domain databases

Conserved Domains Database

More...
CDDi
cd05770 IgC_beta2m, 1 hit

Gene3D Structural and Functional Annotation of Protein Families

More...
Gene3Di
2.60.40.10, 1 hit

Integrated resource of protein families, domains and functional sites

More...
InterProi
View protein in InterPro
IPR015707 B2Microglobulin
IPR007110 Ig-like_dom
IPR036179 Ig-like_dom_sf
IPR013783 Ig-like_fold
IPR003006 Ig/MHC_CS
IPR003597 Ig_C1-set

The PANTHER Classification System

More...
PANTHERi
PTHR19944:SF62 PTHR19944:SF62, 1 hit

Pfam protein domain database

More...
Pfami
View protein in Pfam
PF07654 C1-set, 1 hit

Simple Modular Architecture Research Tool; a protein domain database

More...
SMARTi
View protein in SMART
SM00407 IGc1, 1 hit

Superfamily database of structural and functional annotation

More...
SUPFAMi
SSF48726 SSF48726, 1 hit

PROSITE; a protein domain and family database

More...
PROSITEi
View protein in PROSITE
PS50835 IG_LIKE, 1 hit
PS00290 IG_MHC, 1 hit

<p>This section displays by default the canonical protein sequence and upon request all isoforms described in the entry. It also includes information pertinent to the sequence(s), including <a href="http://www.uniprot.org/help/sequence_length">length</a> and <a href="http://www.uniprot.org/help/sequences">molecular weight</a>. The information is filed in different subsections. The current subsections and their content are listed below:<p><a href='/help/sequences_section' target='_top'>More...</a></p>Sequencei

<p>This subsection of the <a href="http://www.uniprot.org/help/sequences_section">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> displayed by default in the entry is complete or not.<p><a href='/help/sequence_status' target='_top'>More...</a></p>Sequence statusi: Complete.

<p>This subsection of the <a href="http://www.uniprot.org/help/sequences_section">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> displayed by default in the entry is in its mature form or if it represents the precursor.<p><a href='/help/sequence_processing' target='_top'>More...</a></p>Sequence processingi: The displayed sequence is further processed into a mature form.

P01888-1 [UniParc]FASTAAdd to basket
« Hide
        10         20         30         40         50
MARFVALVLL GLLSLSGLDA IQRPPKIQVY SRHPPEDGKP NYLNCYVYGF
60 70 80 90 100
HPPQIEIDLL KNGEKIKSEQ SDLSFSKDWS FYLLSHAEFT PNSKDQYSCR
110
VKHVTLEQPR IVKWDRDL
Length:118
Mass (Da):13,677
Last modified:February 1, 1994 - v2
<p>The checksum is a form of redundancy check that is calculated from the sequence. It is useful for tracking sequence updates.</p> <p>It should be noted that while, in theory, two different sequences could have the same checksum value, the likelihood that this would happen is extremely low.</p> <p>However UniProtKB may contain entries with identical sequences in case of multiple genes (paralogs).</p> <p>The checksum is computed as the sequence 64-bit Cyclic Redundancy Check value (CRC64) using the generator polynomial: x<sup>64</sup> + x<sup>4</sup> + x<sup>3</sup> + x + 1. The algorithm is described in the ISO 3309 standard. </p> <p class="publication">Press W.H., Flannery B.P., Teukolsky S.A. and Vetterling W.T.<br /> <strong>Cyclic redundancy and other checksums</strong><br /> <a href="http://www.nrbook.com/b/bookcpdf.php">Numerical recipes in C 2nd ed., pp896-902, Cambridge University Press (1993)</a>)</p> Checksum:i140854676D3332E6
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the ‘Sequence’ section reports difference(s) between the canonical sequence (displayed by default in the entry) and the different sequence submissions merged in the entry. These various submissions may originate from different sequencing projects, different types of experiments, or different biological samples. Sequence conflicts are usually of unknown origin.<p><a href='/help/conflict' target='_top'>More...</a></p>Sequence conflicti37D → N AA sequence (PubMed:6174509).Curated1
Sequence conflicti92N → D AA sequence (PubMed:6174509).Curated1
Sequence conflicti96Q → E AA sequence (PubMed:6174509).Curated1

Sequence databases

Select the link destinations:

EMBL nucleotide sequence database

More...
EMBLi

GenBank nucleotide sequence database

More...
GenBanki

DNA Data Bank of Japan; a nucleotide sequence database

More...
DDBJi
Links Updated
X69084 mRNA Translation: CAA48828.1
AY911322 mRNA Translation: AAW82090.1
BC118352 mRNA Translation: AAI18353.1

Protein sequence database of the Protein Information Resource

More...
PIRi
I46000 MGBOB2

NCBI Reference Sequences

More...
RefSeqi
NP_776318.1, NM_173893.3
XP_001251108.1, XM_001251107.5
XP_002691165.1, XM_002691119.3

Genome annotation databases

Ensembl eukaryotic genome annotation project

More...
Ensembli
ENSBTAT00000016359; ENSBTAP00000016359; ENSBTAG00000012330

Database of genes from NCBI RefSeq genomes

More...
GeneIDi
280729
783680

KEGG: Kyoto Encyclopedia of Genes and Genomes

More...
KEGGi
bta:280729
bta:783680

<p>This section provides links to proteins that are similar to the protein sequence(s) described in this entry at different levels of sequence identity thresholds (100%, 90% and 50%) based on their membership in UniProt Reference Clusters (<a href="http://www.uniprot.org/help/uniref">UniRef</a>).<p><a href='/help/similar_proteins_section' target='_top'>More...</a></p>Similar proteinsi

<p>This section is used to point to information related to entries and found in data collections other than UniProtKB.<p><a href='/help/cross_references_section' target='_top'>More...</a></p>Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X69084 mRNA Translation: CAA48828.1
AY911322 mRNA Translation: AAW82090.1
BC118352 mRNA Translation: AAI18353.1
PIRiI46000 MGBOB2
RefSeqiNP_776318.1, NM_173893.3
XP_001251108.1, XM_001251107.5
XP_002691165.1, XM_002691119.3

3D structure databases

Select the link destinations:

Protein Data Bank Europe

More...
PDBei

Protein Data Bank RCSB

More...
RCSB PDBi

Protein Data Bank Japan

More...
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1BMGX-ray2.50A21-118[»]
2XFXX-ray1.90B20-118[»]
3L9RX-ray2.30B/D/F/H21-118[»]
3PWVX-ray2.70B/E21-118[»]
4F7CX-ray2.86B/D21-118[»]
4F7EX-ray2.40B21-118[»]
4IIQX-ray2.86C21-118[»]
4L8SX-ray2.90C21-118[»]
4L9LX-ray3.40C21-118[»]
4LCCX-ray3.26C21-118[»]
SMRiP01888
ModBaseiSearch...
PDBe-KBiSearch...

Protein-protein interaction databases

STRINGi9913.ENSBTAP00000016359

PTM databases

CarbonylDBiP01888

Proteomic databases

PaxDbiP01888
PeptideAtlasiP01888
PRIDEiP01888

Genome annotation databases

EnsembliENSBTAT00000016359; ENSBTAP00000016359; ENSBTAG00000012330
GeneIDi280729
783680
KEGGibta:280729
bta:783680

Organism-specific databases

Comparative Toxicogenomics Database

More...
CTDi
567

Phylogenomic databases

eggNOGiENOG410J15A Eukaryota
ENOG410YTDG LUCA
GeneTreeiENSGT00690000102227
HOGENOMiHOG000043084
InParanoidiP01888
KOiK08055
OMAiHTEFTPT
OrthoDBi1556447at2759
TreeFamiTF334167

Enzyme and pathway databases

ReactomeiR-BTA-1236974 ER-Phagosome pathway
R-BTA-1236977 Endosomal/Vacuolar pathway
R-BTA-198933 Immunoregulatory interactions between a Lymphoid and a non-Lymphoid cell
R-BTA-2424491 DAP12 signaling
R-BTA-6798695 Neutrophil degranulation
R-BTA-983170 Antigen Presentation: Folding, assembly and peptide loading of class I MHC

Miscellaneous databases

EvolutionaryTraceiP01888

Gene expression databases

BgeeiENSBTAG00000012330 Expressed in 10 organ(s), highest expression level in spleen

Family and domain databases

CDDicd05770 IgC_beta2m, 1 hit
Gene3Di2.60.40.10, 1 hit
InterProiView protein in InterPro
IPR015707 B2Microglobulin
IPR007110 Ig-like_dom
IPR036179 Ig-like_dom_sf
IPR013783 Ig-like_fold
IPR003006 Ig/MHC_CS
IPR003597 Ig_C1-set
PANTHERiPTHR19944:SF62 PTHR19944:SF62, 1 hit
PfamiView protein in Pfam
PF07654 C1-set, 1 hit
SMARTiView protein in SMART
SM00407 IGc1, 1 hit
SUPFAMiSSF48726 SSF48726, 1 hit
PROSITEiView protein in PROSITE
PS50835 IG_LIKE, 1 hit
PS00290 IG_MHC, 1 hit

ProtoNet; Automatic hierarchical classification of proteins

More...
ProtoNeti
Search...

MobiDB: a database of protein disorder and mobility annotations

More...
MobiDBi
Search...

<p>This section provides general information on the entry.<p><a href='/help/entry_information_section' target='_top'>More...</a></p>Entry informationi

<p>This subsection of the ‘Entry information’ section provides a mnemonic identifier for a UniProtKB entry, but it is not a stable identifier. Each reviewed entry is assigned a unique entry name upon integration into UniProtKB/Swiss-Prot.<p><a href='/help/entry_name' target='_top'>More...</a></p>Entry nameiB2MG_BOVIN
<p>This subsection of the ‘Entry information’ section provides one or more accession number(s). These are stable identifiers and should be used to cite UniProtKB entries. Upon integration into UniProtKB, each entry is assigned a unique accession number, which is called ‘Primary (citable) accession number’.<p><a href='/help/accession_numbers' target='_top'>More...</a></p>AccessioniPrimary (citable) accession number: P01888
Secondary accession number(s): Q148G6, Q56K05
<p>This subsection of the ‘Entry information’ section shows the date of integration of the entry into UniProtKB, the date of the last sequence update and the date of the last annotation modification (‘Last modified’). The version number for both the entry and the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> are also displayed.<p><a href='/help/entry_history' target='_top'>More...</a></p>Entry historyiIntegrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: February 1, 1994
Last modified: December 11, 2019
This is version 160 of the entry and version 2 of the sequence. See complete history.
<p>This subsection of the ‘Entry information’ section indicates whether the entry has been manually annotated and reviewed by UniProtKB curators or not, in other words, if the entry belongs to the Swiss-Prot section of UniProtKB (<strong>reviewed</strong>) or to the computer-annotated TrEMBL section (<strong>unreviewed</strong>).<p><a href='/help/entry_status' target='_top'>More...</a></p>Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

<p>This section contains any relevant information that doesn’t fit in any other defined sections<p><a href='/help/miscellaneous_section' target='_top'>More...</a></p>Miscellaneousi

Keywords - Technical termi

3D-structure, Direct protein sequencing, Reference proteome

Documents

  1. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  2. SIMILARITY comments
    Index of protein domains and families
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