Reviewed, UniProtKB/Swiss-Prot P11836 (CD20_HUMAN)

Names and origin

Protein names

Recommended name:
    B-lymphocyte antigen CD20
Alternative name(s):
    Membrane-spanning 4-domains subfamily A member 1
    B-lymphocyte surface antigen B1
    Leu-16
    Bp35
    CD_antigen=CD20

Gene names

Name:	MS4A1
Synonyms:	CD20

Organism

Homo sapiens (Human) [Complete proteome]

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

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

Protein attributes

Sequence length	297 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	This protein may be involved in the regulation of B-cell activation and proliferation.
Subcellular location	Membrane; Multi-pass membrane protein.
Tissue specificity	Expressed on B-cells.
Post-translational modification	Phosphorylated. Might be functionally regulated by protein kinase(s). Ref.9
Pharmaceutical use	Monoclonal antibodies(mAb) against CD20 are used to treat B-cell non-Hodgkin's lymphoma (NHL). These antibodies include Rituximab (Mabthera), Britumomab (Zevalin) and Tositumomab (Bexxar). CD20 engaged by mAb can generate transmembrane signals capable of directly controlling cell growth and triggering cell death in certain tumors. Alternatively, mAb can mediate complement-dependent cytotoxicity.
Sequence similarities	Belongs to the MS4A family.
Caution	Epitope 1, mapped in Ref.8, is predicted to be buried in the membrane. Its accessibility to the extracellular space, and thus to antibody recognition, is not explained.

Ontologies

Keywords
Biological process	B-cell activation
Cellular component	Membrane
Domain	Transmembrane
PTM	Disulfide bond Phosphoprotein
Technical term	3D-structure Complete proteome Pharmaceutical
Gene Ontology (GO)
Biological process	B cell activation Inferred from electronic annotation. Source: UniProtKB-KW immune response Traceable author statement. Source: ProtInc signal transduction Inferred from electronic annotation. Source: InterPro
Cellular component	focal adhesion Inferred from direct assay. Source: HPA integral to plasma membrane Traceable author statement. Source: ProtInc nucleus Inferred from direct assay. Source: HPA
Molecular function	receptor activity Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 297

297

B-lymphocyte antigen CD20

PRO_0000158627

Regions

Topological domain

1 – 63

63

Cytoplasmic Potential

Transmembrane

64 – 84

21

Potential

Transmembrane

85 – 105

21

Potential

Transmembrane

121 – 141

21

Potential

Transmembrane

189 – 209

21

Potential

Topological domain

210 – 297

88

Cytoplasmic Potential

Region

74 – 80

7

Epitope 1

Region

146 – 160

15

Epitope 2

Region

168 – 175

8

Epitope 3 (recognized by antibodies, including Rituximab)

Amino acid modifications

Modified residue

35

1

Phosphoserine Ref.9

Modified residue

36

1

Phosphoserine Ref.9

Disulfide bond

111 ↔ 220

Probable

Experimental info

Mutagenesis

159

1

T → K: Abrogates recognition by some antibodies; when associated with D-163 and D-166. Slight decrease of rituximab binding; when associated with D-163 and D-166. Ref.8

Mutagenesis

163

1

N → D: Decreased binding of some antibodies. No effect on rituximab binding. Ref.8

Mutagenesis

166

1

N → D: Decreased binding of some antibodies. No effect on rituximab binding. Ref.8

Mutagenesis

170

1

A → S: Abrogates recognition by therapeutic antibodies, including rituximab; when associated with S-172. Ref.8

Mutagenesis

172

1

P → S: Marked reduction in rituximab binding. Abrogates recognition by antibodies, including rituximab; when associated with S-170. Ref.8

Sequence conflict

13

1

P → L in CAA30179. Ref.3

Sequence conflict

13

1

P → L in CAA30180. Ref.3

Sequence conflict

71

1

M → I in AAA88911. Ref.4

Secondary structure

1

.

.

.

.

.

297

Helix Strand Turn

Details...

Helix

172 – 174

3

Helix

178 – 184

7

Sequences

	Sequence		Length	Mass (Da)
	P11836-1 [UniParc]. Last modified October 1, 1989. Version 1. Checksum: AC5420F8B626BDD1	FASTA	297	33,077
	10 20 30 40 50 60 MTTPRNSVNG TFPAEPMKGP IAMQSGPKPL FRRMSSLVGP TQSFFMRESK TLGAVQIMNG 70 80 90 100 110 120 LFHIALGGLL MIPAGIYAPI CVTVWYPLWG GIMYIISGSL LAATEKNSRK CLVKGKMIMN 130 140 150 160 170 180 SLSLFAAISG MILSIMDILN IKISHFLKME SLNFIRAHTP YINIYNCEPA NPSEKNSPST 190 200 210 220 230 240 QYCYSIQSLF LGILSVMLIF AFFQELVIAG IVENEWKRTC SRPKSNIVLL SAEEKKEQTI 250 260 270 280 290 EIKEEVVGLT ETSSQPKNEE DIEIIPIQEE EEEETETNFP EPPQDQESSP IENDSSP

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Analysis of two cDNA clones encoding the B lymphocyte antigen CD20 (B1, Bp35), a type III integral membrane protein." Stamenkovic I., Seed B. J. Exp. Med. 167:1975-1980(1988) [PubMed: 3260267] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[2]	"Isolation and structure of a cDNA encoding the B1 (CD20) cell-surface antigen of human B lymphocytes." Tedder T.F., Streuli M., Schlossman S.F., Saito H. Proc. Natl. Acad. Sci. U.S.A. 85:208-212(1988) [PubMed: 2448768] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[3]	"Molecular cloning of the human B cell CD20 receptor predicts a hydrophobic protein with multiple transmembrane domains." Einfeld D.A., Brown J.P., Valentine M.A., Clark E.A., Ledbetter J.A. EMBO J. 7:711-717(1988) [PubMed: 2456210] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[4]	"Structure of the gene encoding the human B lymphocyte differentiation antigen CD20 (B1)." Tedder T.F., Klejman G., Schlossman S.F., Saito H. J. Immunol. 142:2560-2568(1989) [PubMed: 2466899] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[5]	"Human chromosome 11 DNA sequence and analysis including novel gene identification." Taylor T.D., Noguchi H., Totoki Y., Toyoda A., Kuroki Y., Dewar K., Lloyd C., Itoh T., Takeda T., Kim D.-W., She X., Barlow K.F., Bloom T., Bruford E., Chang J.L., Cuomo C.A., Eichler E., FitzGerald M.G. , Jaffe D.B., LaButti K., Nicol R., Park H.-S., Seaman C., Sougnez C., Yang X., Zimmer A.R., Zody M.C., Birren B.W., Nusbaum C., Fujiyama A., Hattori M., Rogers J., Lander E.S., Sakaki Y. Nature 440:497-500(2006) [PubMed: 16554811] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[6]	Mural R.J., Istrail S., Sutton G.G., Florea L., Halpern A.L., Mobarry C.M., Lippert R., Walenz B., Shatkay H., Dew I., Miller J.R., Flanigan M.J., Edwards N.J., Bolanos R., Fasulo D., Halldorsson B.V., Hannenhalli S., Turner R. , Yooseph S., Lu F., Nusskern D.R., Shue B.C., Zheng X.H., Zhong F., Delcher A.L., Huson D.H., Kravitz S.A., Mouchard L., Reinert K., Remington K.A., Clark A.G., Waterman M.S., Eichler E.E., Adams M.D., Hunkapiller M.W., Myers E.W., Venter J.C. Submitted (JUL-2005) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[7]	"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: Lymph.
[8]	"The biological activity of human CD20 monoclonal antibodies is linked to unique epitopes on CD20." Teeling J.L., Mackus W.J.M., Wiegman L.J.J.M., van den Brakel J.H.N., Beers S.A., French R.R., van Meerten T., Ebeling S., Vink T., Slootstra J.W., Parren P.W.H.I., Glennie M.J., van de Winkel J.G.J. J. Immunol. 177:362-371(2006) [PubMed: 16785532] [Abstract] Cited for: EPITOPE MAPPING, MUTAGENESIS OF THR-159; ASN-163; ASN-166; ALA-170 AND PRO-172.
[9]	"Phosphorylation analysis of primary human T lymphocytes using sequential IMAC and titanium oxide enrichment." Carrascal M., Ovelleiro D., Casas V., Gay M., Abian J. J. Proteome Res. 7:5167-5176(2008) [PubMed: 19367720] [Abstract] Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-35 AND SER-36, MASS SPECTROMETRY. Tissue: T-cell.
+	Additional computationally mapped references.

Web resources

Wikipedia

CD20 entry

Cross-references

Sequence databases

EMBLGenBankDDBJ

X12530 mRNA. Translation: CAA31046.1.
M27394 Genomic DNA. Translation: AAA35581.1.
X07203 mRNA. Translation: CAA30179.1.
X07204 mRNA. Translation: CAA30180.1.
L23419 , L23415, L23416, L23417 Genomic DNA. Translation: AAA88911.1.
M27395 Genomic DNA. No translation available.
AP003127 Genomic DNA. No translation available.
CH471076 Genomic DNA. Translation: EAW73889.1.
BC002807 mRNA. Translation: AAH02807.1.

IPI

IPI00007880.

PIR

A30586.

RefSeq

NP_068769.2.
NP_690605.1.

UniGene

Hs.712553

3D structure databases

PDBPDBe

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1S8B	model	-	A	1-297	[»]
2OSL	X-ray	2.60	P/Q	163-187	[»]
3BKY	X-ray	2.61	P	163-187	[»]

ModBase

Search...

Protein-protein interaction databases

STRING

P11836.

Protein family/group databases

TCDB

1.A.37.1.1. CD20 Ca2+ channel (CD20) family.

PTM databases

PhosphoSite

P11836.

Proteomic databases

PRIDE

P11836.

Genome annotation databases

Ensembl

ENST00000345732; ENSP00000314620; ENSG00000156738; Homo sapiens. [Genome view]
ENST00000389939; ENSP00000374589; ENSG00000156738; Homo sapiens. [Genome view]
ENST00000416059; ENSP00000412506; ENSG00000156738; Homo sapiens. [Genome view]

GeneID

931.

KEGG

hsa:931.

UCSC

uc001npp.1. human.

Organism-specific databases

CTD

931.

GeneCards

GC11P059979.

H-InvDB

HIX0009670.

HGNC

HGNC:7315. MS4A1.

HPA

CAB000015.
HPA014341.
HPA014391.

MIM

112210. gene.

PharmGKB

PA31111.

GenAtlas

Search...

Phylogenomic databases

HOGENOM

P11836.

HOVERGEN

P11836.

OMA

FFMRESK.

Gene expression databases

ArrayExpress

P11836.

Bgee

P11836.

CleanEx

HS_MS4A1.

Genevestigator

P11836.

GermOnline

ENSG00000156738. Homo sapiens.

Family and domain databases

InterPro

IPR007237. CD20IgEFc_rcpt_B.
[Graphical view]

Pfam

PF04103. CD20. 1 hit.
[Graphical view]

ProtoNet

Search...

Other Resources

DrugBank

DB00078. Ibritumomab.
DB00073. Rituximab.
DB00081. Tositumomab.

NextBio

3860.

SOURCE

Search...

Entry information

Entry name

CD20_HUMAN

Accession

Primary (citable) accession number: P11836
Secondary accession number(s): A6NMS4, P08984, Q13963

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1989
Last sequence update:	October 1, 1989
Last modified:	November 3, 2009
This is version 99 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.