Reviewed, UniProtKB/Swiss-Prot P61769 (B2MG_HUMAN)

Names and origin

Protein names

Recommended name:
    Beta-2-microglobulin
Cleaved into the following 1 chains:
    1- Recommended name:
            Beta-2-microglobulin form pI 5.3

Gene names

Name:	B2M
ORF Names:	CDABP0092, HDCMA22P

Organism

Homo sapiens (Human)

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo

Protein attributes

Sequence length	119 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Beta-2-microglobulin is the beta-chain of major histocompatibility complex class I molecules.
Subcellular location	Secreted.
Post-translational modification	Glycation of Ile-21 is observed in long-term hemodialysis patients.
Involvement in disease	Defects in B2M are the cause of hypercatabolic hypoproteinemia [MIM:241600]. Affected individuals show marked reduction in serum concentrations of immunoglobulin and albumin, probably due to rapid degradation.
Sequence similarities	Belongs to the beta-2-microglobulin family. Contains 1 Ig-like C1-type (immunoglobulin-like) domain.

Ontologies

Keywords
Biological process	Immune response
Cellular component	MHC I Secreted
Disease	Disease mutation
Domain	Immunoglobulin domain Signal
PTM	Glycation Glycoprotein Pyrrolidone carboxylic acid
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Cellular component	Golgi membrane Inferred from Experiment. Source: Reactome early endosome membrane Inferred from Experiment. Source: Reactome plasma membrane Inferred from Experiment. Source: Reactome
Molecular function	protein binding Inferred from physical interaction. Source: IntAct
Complete GO annotation...

Binary interactions

With	Entry	#Exp.	IntAct	Notes
CD1B	P29016	2	EBI-714718,EBI-1033762

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Molecule processing

Signal peptide

1 – 20

20

Chain

21 – 119

99

Beta-2-microglobulin

Chain

22 – 119

98

Beta-2-microglobulin form pI 5.3

Regions

Domain

25 – 113

89

Ig-like C1-type

Amino acid modifications

Modified residue

22

1

Pyrrolidone carboxylic acid; in form pI 5.3

Glycosylation

21

1

N-linked (Glc) (glycation); in hemodialysis-associated amyloidosis

Glycosylation

39

1

N-linked (Glc) (glycation); in vitro

Glycosylation

61

1

N-linked (Glc) (glycation); in vitro

Glycosylation

68

1

N-linked (Glc) (glycation); in vitro

Glycosylation

78

1

N-linked (Glc) (glycation); in vitro

Glycosylation

111

1

N-linked (Glc) (glycation); in vitro

Glycosylation

114

1

N-linked (Glc) (glycation); in vitro

Disulfide bond

45 ↔ 100

Natural variations

Natural variant

11

1

A → P in hypercatabolic hypoproteinemia; lower levels of beta-2-microglobulin, MHC class I and FcRn proteins.

Experimental info

Sequence conflict

20

1

A → G in AAA51811. Ref.1

Sequence conflict

52

1

P → Q in AAA51811. Ref.1

Sequence conflict

86

1

Y → YS Ref.7

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

.

.

.

119

Helix Strand Turn

Details...

Beta strand

26 – 33

8

Beta strand

41 – 53

13

Beta strand

56 – 61

6

Beta strand

82 – 90

9

Beta strand

98 – 103

6

Beta strand

111 – 114

4

Sequences

	Sequence		Length	Mass (Da)
	P61769-1 [UniParc]. Last modified July 21, 1986. Version 1. Checksum: AFD2DBEF07DCEF27	FASTA	119	13,715
	10 20 30 40 50 60 MSRSVALAVL ALLSLSGLEA IQRTPKIQVY SRHPAENGKS NFLNCYVSGF HPSDIEVDLL 70 80 90 100 110 KNGERIEKVE HSDLSFSKDW SFYLLYYTEF TPTEKDEYAC RVNHVTLSQP KIVKWDRDM

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"The human beta 2-microglobulin gene. Primary structure and definition of the transcriptional unit." Guessow D., Rein R., Ginjaar I., Hochstenbach F., Seemann G., Kottman A., Ploegh H.L. J. Immunol. 139:3132-3138(1987) [PubMed: 3312414] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Human mRNA for beta 2-microglobulin." Matsumoto K., Minamitani T. Submitted (DEC-1998) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[3]	"A novel gene from human dendritic cell." Zhao Z., Huang X., Li N., Zhu X., Cao X. Submitted (JUN-1998) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Dendritic cell.
[4]	"Pediatric leukemia cDNA sequencing project." Zhou J., Yu W., Tang H., Mei G., Tsang Y.T.M., Bouck J., Gibbs R.A., Margolin J.F. Submitted (JUL-2000) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Leukemia.
[5]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed: 15489334] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Eye and Skin.
[6]	"The beta-2-microglobulin mRNA in human Daudi cells has a mutated initiation codon but is still inducible by interferon." Rosa F., Berissi H., Weissenbach J., Maroteaux L., Fellous M., Revel M. EMBO J. 2:239-243(1983) [PubMed: 11894933] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 1-21.
[7]	"Use of synthetic oligonucleotides as hybridization probes: isolation of cloned cDNA sequences for human beta 2-microglobulin." Suggs S.V., Wallace R.B., Hirose T., Kawashima E.H., Itakura K. Proc. Natl. Acad. Sci. U.S.A. 78:6613-6617(1981) [PubMed: 6171820] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 10-119.
[8]	"The complete amino acid sequence of beta 2-microglobulin." Cunningham B.A., Wang J.L., Berggard I., Peterson P.A. Biochemistry 12:4811-4822(1973) [PubMed: 4586824] [Abstract] Cited for: PROTEIN SEQUENCE OF 21-119.
[9]	"Amino acid sequence of a modified beta 2-microglobulin in renal failure patient urine and long-term dialysis patient blood." Momoi T., Suzuki M., Titani K., Hisanaga S., Ogawa H., Saito A. Clin. Chim. Acta 236:135-144(1995) [PubMed: 7554280] [Abstract] Cited for: PROTEIN SEQUENCE OF 22-119. Tissue: Urine.
[10]	"Glycation of human beta 2-microglobulin in patients with hemodialysis-associated amyloidosis: identification of the glycated sites." Miyata T., Inagi R., Wada Y., Ueda Y., Iida Y., Takahashi M., Taniguchi N., Maeda K. Biochemistry 33:12215-12221(1994) [PubMed: 7918443] [Abstract] Cited for: GLYCATION AT ILE-21; LYS-39; LYS-61; LYS-68; LYS-78; LYS-111 AND LYS-114, MASS SPECTROMETRY.
[11]	"Structure of the human class I histocompatibility antigen, HLA-A2." Bjorkman P.J., Saper M.A., Samraoui B., Bennett W.S., Strominger J.L., Wiley D.C. Nature 329:506-512(1987) [PubMed: 3309677] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (3.5 ANGSTROMS).
[12]	"Refined structure of the human histocompatibility antigen HLA-A2 at 2.6-A resolution." Saper M.A., Bjorkman P.J., Wiley D.C. J. Mol. Biol. 219:277-319(1991) [PubMed: 2038058] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.6 ANGSTROMS).
[13]	"The three-dimensional structure of a class I major histocompatibility complex molecule missing the alpha 3 domain of the heavy chain." Collins E.J., Garboczi D.N., Karpusas M.N., Wiley D.C. Proc. Natl. Acad. Sci. U.S.A. 92:1218-1221(1995) [PubMed: 7862664] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.3 ANGSTROMS).
[14]	"Bound water structure and polymorphic amino acids act together to allow the binding of different peptides to MHC class I HLA-B53." Smith K.J., Reid S.W., Harlos K., McMichael A.J., Stuart D.I., Bell J.I., Jones E.Y. Immunity 4:215-228(1996) [PubMed: 8624812] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.3 ANGSTROMS).
[15]	"1H NMR assignments and secondary structure of human beta 2-microglobulin in solution." Okon M., Bray P., Vucelic D. Biochemistry 31:8906-8915(1992) [PubMed: 1390678] [Abstract] Cited for: STRUCTURE BY NMR.
[16]	"Familial hypercatabolic hypoproteinemia caused by deficiency of the neonatal Fc receptor, FcRn, due to a mutant beta2-microglobulin gene." Wani M.A., Haynes L.D., Kim J., Bronson C.L., Chaudhury C., Mohanty S., Waldmann T.A., Robinson J.M., Anderson C.L. Proc. Natl. Acad. Sci. U.S.A. 103:5084-5089(2006) [PubMed: 16549777] [Abstract] Cited for: VARIANT HYPERCATABOLIC HYPOPROTEINEMIA PRO-11, CHARACTERIZATION OF VARIANT HYPERCATABOLIC HYPOPROTEINEMIA PRO-11.
+	Additional computationally mapped references.

Web resources

Wikipedia

Beta-2-microglobulin entry

Cross-references

Sequence databases

EMBLGenBankDDBJ

M17987, M17986 Genomic DNA. Translation: AAA51811.1.
AB021288 mRNA. Translation: BAA35182.1.
AF072097 Genomic DNA. Translation: AAD48083.1.
AY007153 mRNA. Translation: AAG02006.1.
BC032589 mRNA. Translation: AAH32589.1.
BC064910 mRNA. Translation: AAH64910.1.
V00567 mRNA. Translation: CAA23830.1.

PIR

MGHUB2. A90976.

RefSeq

NP_004039.1.

UniGene

Hs.626605

3D structure databases

PDBMSD

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1A1M	X-ray	2.30	B	21-119	[»]
1A1N	X-ray	2.00	B	21-119	[»]
1A1O	X-ray	2.30	B	21-119	[»]
1A6Z	X-ray	2.60	B/D	21-119	[»]
1A9B	X-ray	3.20	B/E	21-119	[»]
1A9E	X-ray	2.50	B	21-119	[»]
1AGB	X-ray	2.20	B	21-119	[»]
1AGC	X-ray	2.10	B	21-119	[»]
1AGD	X-ray	2.05	B	21-119	[»]
1AGE	X-ray	2.30	B	21-119	[»]
1AGF	X-ray	2.20	B	21-119	[»]
1AKJ	X-ray	2.65	B	21-119	[»]
1AO7	X-ray	2.60	B	21-119	[»]
1B0G	X-ray	2.50	B/E	21-119	[»]
1B0R	X-ray	2.90	B	21-119	[»]
1BD2	X-ray	2.50	B	21-119	[»]
1C16	X-ray	3.10	B/D/F/H	21-119	[»]
1CE6	X-ray	2.90	B	21-119	[»]
1CG9	X-ray	2.70	B	21-119	[»]
1DE4	X-ray	2.80	B/E/H	21-119	[»]
1DUY	X-ray	2.15	B/E	21-119	[»]
1DUZ	X-ray	1.80	B/E	21-119	[»]
1E27	X-ray	2.20	B	21-119	[»]
1E28	X-ray	3.00	B	21-119	[»]
1EEY	X-ray	2.25	B/E	21-119	[»]
1EEZ	X-ray	2.30	B/E	21-119	[»]
1EFX	X-ray	3.00	B	21-119	[»]
1EXU	X-ray	2.70	B	21-119	[»]
1GZP	X-ray	2.80	B	21-119	[»]
1GZQ	X-ray	2.26	B	21-119	[»]
1HHG	X-ray	2.60	B/E	21-119	[»]
1HHH	X-ray	3.00	B	21-119	[»]
1HHI	X-ray	2.50	B/E	21-119	[»]
1HHJ	X-ray	2.50	B/E	21-119	[»]
1HHK	X-ray	2.50	B/E	21-119	[»]
1HLA	X-ray	3.50	M	21-117	[»]
1HSA	X-ray	2.10	B/E	21-119	[»]
1HSB	X-ray	1.90	B	21-119	[»]
1I1F	X-ray	2.80	B/E	21-119	[»]
1I1Y	X-ray	2.20	B/E	21-119	[»]
1I4F	X-ray	1.40	B	21-119	[»]
1I7R	X-ray	2.20	B/E	21-119	[»]
1I7T	X-ray	2.80	B/E	21-119	[»]
1I7U	X-ray	1.80	B/E	21-119	[»]
1IM3	X-ray	2.20	B/F/J/N	21-119	[»]
1IM9	X-ray	2.80	B/F	21-119	[»]
1JF1	X-ray	1.85	B	21-119	[»]
1JGD	X-ray	1.90	B	21-119	[»]
1JGE	X-ray	2.10	B	21-119	[»]
1JHT	X-ray	2.15	B	21-119	[»]
1JNJ	NMR	-	A	21-119	[»]
1K5N	X-ray	1.09	B	21-119	[»]
1KPR	X-ray	2.80	B/D	21-119	[»]
1KTL	X-ray	3.10	B/D	21-119	[»]
1LDS	X-ray	1.80	A	21-119	[»]
1LP9	X-ray	2.00	B/I	21-119	[»]
1M05	X-ray	1.90	B/D	21-119	[»]
1M6O	X-ray	1.60	B	21-119	[»]
1MHE	X-ray	2.85	B/D	21-119	[»]
1MI5	X-ray	2.50	B	21-119	[»]
1N2R	X-ray	1.70	B	21-119	[»]
1OF2	X-ray	2.20	B	21-119	[»]
1OGA	X-ray	1.40	B	21-119	[»]
1OGT	X-ray	1.47	B	21-119	[»]
1ONQ	X-ray	2.15	B/D	21-119	[»]
1P7Q	X-ray	3.40	B	21-119	[»]
1PY4	X-ray	2.90	A/B/C/D	21-119	[»]
1Q94	X-ray	2.40	B/E	21-119	[»]
1QEW	X-ray	2.20	B	21-119	[»]
1QLF	X-ray	2.65	B	21-119	[»]
1QQD	X-ray	2.70	B	21-118	[»]
1QR1	X-ray	2.40	B/E	21-119	[»]
1QRN	X-ray	2.80	B	21-119	[»]
1QSE	X-ray	2.80	B	21-119	[»]
1QSF	X-ray	2.80	B	21-119	[»]
1QVO	X-ray	2.22	B/E	21-119	[»]
1R3H	X-ray	2.50	B/D/F/H	21-119	[»]
1S8D	X-ray	2.20	B	21-119	[»]
1S9W	X-ray	2.20	B	21-119	[»]
1S9X	X-ray	2.50	B	21-119	[»]
1S9Y	X-ray	2.30	B	21-119	[»]
1SYS	X-ray	2.40	B	21-119	[»]
1SYV	X-ray	1.70	B	21-119	[»]
1T1W	X-ray	2.20	B	21-119	[»]
1T1X	X-ray	2.20	B	21-119	[»]
1T1Y	X-ray	2.00	B	21-119	[»]
1T1Z	X-ray	1.90	B	21-119	[»]
1T20	X-ray	2.20	B	21-119	[»]
1T21	X-ray	2.19	B	21-119	[»]
1T22	X-ray	2.20	B	21-119	[»]
1TMC	X-ray	2.30	B	21-119	[»]
1TVB<