P10966 (CD8B_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
T-cell surface glycoprotein CD8 beta chain

Alternative name(s):
CD_antigen=CD8b

Gene names

Name:	CD8B
Synonyms:	CD8B1

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	210 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	Identifies cytotoxic/suppressor T-cells that interact with MHC class I bearing targets. CD8 is thought to play a role in the process of T-cell mediated killing.
Subunit structure	In general heterodimer of an alpha and a beta chain linked by two disulfide bonds.
Subcellular location	Isoform 1: Cell membrane; Single-pass type I membrane protein Probable. Isoform 2: Cell membrane; Single-pass type I membrane protein Probable. Isoform 3: Secreted Probable. Isoform 4: Cell membrane; Single-pass type I membrane protein Probable. Isoform 5: Cell membrane; Single-pass type I membrane protein Probable. Isoform 6: Secreted Probable. Isoform 7: Secreted Probable. Isoform 8: Secreted Probable.
Tissue specificity	Isoform 1, isoform 3, isoform 5, isoform 6, isoform 7 and isoform 8 are expressed in both thymus and peripheral CD8+ T-cells. Expression of isoform 1 is higher in thymus CD8+ T-cells than in peripheral CD8+ T-cells. Expression of isoform 6 is higher in peripheral CD8+ T-cells than in thymus CD8+ T-cells. Ref.7
Post-translational modification	Phosphorylated as a consequence of T-cell activation Potential.
Sequence similarities	Contains 1 Ig-like V-type (immunoglobulin-like) domain.
Sequence caution	The sequence AAD13877.1 differs from that shown. Reason: Erroneous gene model prediction.

Ontologies

Keywords
Biological process	Adaptive immunity Immunity
Cellular component	Cell membrane Membrane Secreted
Coding sequence diversity	Alternative splicing
Domain	Immunoglobulin domain Signal Transmembrane Transmembrane helix
PTM	Disulfide bond Glycoprotein Phosphoprotein
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological process	T cell activation Non-traceable author statement. Source: UniProtKB immune response Non-traceable author statement. Source: UniProtKB regulation of defense response to virus by virus Traceable author statement. Source: Reactome regulation of immune response Traceable author statement. Source: Reactome transmembrane receptor protein tyrosine kinase signaling pathway Non-traceable author statement. Source: UniProtKB viral reproduction Traceable author statement. Source: Reactome
Cellular component	T cell receptor complex Non-traceable author statement. Source: UniProtKB early endosome Traceable author statement. Source: Reactome extracellular region Inferred from electronic annotation. Source: UniProtKB-SubCell integral to plasma membrane Traceable author statement. Source: ProtInc
Molecular function	MHC class I protein binding Non-traceable author statement. Source: UniProtKB coreceptor activity Non-traceable author statement. Source: UniProtKB
Complete GO annotation...

Alternative products

This entry describes 8 isoforms produced by alternative splicing. [Align] [Select]
Isoform 1 (identifier: P10966-1) Also known as: M-1; Mbeta1; This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
Isoform 2 (identifier: P10966-2) Also known as: M-3; Mbeta2; The sequence of this isoform differs from the canonical sequence as follows:      208-210: FYK → LRLHPLEKCSRMDY
Isoform 3 (identifier: P10966-3) Also known as: S-1; Sbeta3; The sequence of this isoform differs from the canonical sequence as follows:      166-195: Missing.      208-210: FYK → PQGEGISGTFVPQCLHGYYSNTTTSQKLLNPWILKT
Isoform 4 (identifier: P10966-4) Also known as: M-2; The sequence of this isoform differs from the canonical sequence as follows:      208-210: FYK → KFNIVCLKISGFTTCCCFQILQISREYGFGVLLQKDIGQ
Isoform 5 (identifier: P10966-6) Also known as: Mbeta3; The sequence of this isoform differs from the canonical sequence as follows:      208-210: FYK → PQGEGISGTFVPQCLHGYYSNTTTSQKLLNPWILKT
Sequence annotation (Features)
	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
	Sequence conflict	213	1	I → V in AAI00915. Ref.6
Isoform 6 (identifier: P10966-7) Also known as: Sbeta1; The sequence of this isoform differs from the canonical sequence as follows:      166-195: Missing.
Isoform 7 (identifier: P10966-8) Also known as: Sbeta4; The sequence of this isoform differs from the canonical sequence as follows:      165-210: GPLCSPITLG...RLRFMKQFYK → DFTNKQRIGF...TFNPGEFNGC
Isoform 8 (identifier: P10966-9) Also known as: Sbeta5; The sequence of this isoform differs from the canonical sequence as follows:      166-210: PLCSPITLGL...RLRFMKQFYK → LKGKVYQGPLSPNACMDTTAILQPHRSCLTHGS

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Signal peptide	1 – 21	21
	Chain	22 – 210	189	T-cell surface glycoprotein CD8 beta chain		PRO_0000014643
Regions
	Topological domain	22 – 170	149	Extracellular Potential
	Transmembrane	171 – 191	21	Helical; Potential
	Topological domain	192 – 210	19	Cytoplasmic Potential
	Domain	22 – 132	111	Ig-like V-type
Amino acid modifications
	Modified residue	130	1	Phosphothreonine By similarity
	Modified residue	209	1	Phosphotyrosine Potential
	Glycosylation	102	1	N-linked (GlcNAc...) Potential
	Disulfide bond	41 ↔ 116		Potential
Natural variations
	Alternative sequence	165 – 210	46	GPLCS…KQFYK → DFTNKQRIGFWCPATKRHRS VMSTMWKNERRDTFNPGEFN GC in isoform 7.		VSP_039654
	Alternative sequence	166 – 210	45	PLCSP…KQFYK → LKGKVYQGPLSPNACMDTTA ILQPHRSCLTHGS in isoform 8.		VSP_039655
	Alternative sequence	166 – 195	30	Missing in isoform 3 and isoform 6.		VSP_002492
	Alternative sequence	208 – 210	3	FYK → LRLHPLEKCSRMDY in isoform 2.		VSP_002490
	Alternative sequence	208 – 210	3	FYK → PQGEGISGTFVPQCLHGYYS NTTTSQKLLNPWILKT in isoform 3 and isoform 5.		VSP_002493
	Alternative sequence	208 – 210	3	FYK → KFNIVCLKISGFTTCCCFQI LQISREYGFGVLLQKDIGQ in isoform 4.		VSP_002491
Experimental info
	Sequence conflict	173	1	Missing no nucleotide entry Ref.7
	Sequence conflict	180	1	V → I in AAI00915. Ref.6

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 (M-1) (Mbeta1) [UniParc]. Last modified July 1, 1989. Version 1. Checksum: 675AD919585F4B80	FASTA	210	23,722
	10 20 30 40 50 60 MRPRLWLLLA AQLTVLHGNS VLQQTPAYIK VQTNKMVMLS CEAKISLSNM RIYWLRQRQA 70 80 90 100 110 120 PSSDSHHEFL ALWDSAKGTI HGEEVEQEKI AVFRDASRFI LNLTSVKPED SGIYFCMIVG 130 140 150 160 170 180 SPELTFGKGT QLSVVDFLPT TAQPTKKSTL KKRVCRLPRP ETQKGPLCSP ITLGLLVAGV 190 200 210 LVLLVSLGVA IHLCCRRRRA RLRFMKQFYK
	Isoform 2 (M-3) (Mbeta2) [UniParc]. Checksum: F5D8E834AE123671	FASTA	221	25,027
	10 20 30 40 50 60 MRPRLWLLLA AQLTVLHGNS VLQQTPAYIK VQTNKMVMLS CEAKISLSNM RIYWLRQRQA 70 80 90 100 110 120 PSSDSHHEFL ALWDSAKGTI HGEEVEQEKI AVFRDASRFI LNLTSVKPED SGIYFCMIVG 130 140 150 160 170 180 SPELTFGKGT QLSVVDFLPT TAQPTKKSTL KKRVCRLPRP ETQKGPLCSP ITLGLLVAGV 190 200 210 220 LVLLVSLGVA IHLCCRRRRA RLRFMKQLRL HPLEKCSRMD Y
	Isoform 3 (S-1) (Sbeta3) [UniParc]. Checksum: 79F81C2F066900D3	FASTA	213	24,276
	10 20 30 40 50 60 MRPRLWLLLA AQLTVLHGNS VLQQTPAYIK VQTNKMVMLS CEAKISLSNM RIYWLRQRQA 70 80 90 100 110 120 PSSDSHHEFL ALWDSAKGTI HGEEVEQEKI AVFRDASRFI LNLTSVKPED SGIYFCMIVG 130 140 150 160 170 180 SPELTFGKGT QLSVVDFLPT TAQPTKKSTL KKRVCRLPRP ETQKGRRRRA RLRFMKQPQG 190 200 210 EGISGTFVPQ CLHGYYSNTT TSQKLLNPWI LKT
	Isoform 4 (M-2) [UniParc]. Checksum: 33E6112A23CE59CD	FASTA	246	27,681
	10 20 30 40 50 60 MRPRLWLLLA AQLTVLHGNS VLQQTPAYIK VQTNKMVMLS CEAKISLSNM RIYWLRQRQA 70 80 90 100 110 120 PSSDSHHEFL ALWDSAKGTI HGEEVEQEKI AVFRDASRFI LNLTSVKPED SGIYFCMIVG 130 140 150 160 170 180 SPELTFGKGT QLSVVDFLPT TAQPTKKSTL KKRVCRLPRP ETQKGPLCSP ITLGLLVAGV 190 200 210 220 230 240 LVLLVSLGVA IHLCCRRRRA RLRFMKQKFN IVCLKISGFT TCCCFQILQI SREYGFGVLL QKDIGQ
	Isoform 5 (Mbeta3) [UniParc]. Checksum: 9D6B283609CC0752	FASTA	243	27,246
	10 20 30 40 50 60 MRPRLWLLLA AQLTVLHGNS VLQQTPAYIK VQTNKMVMLS CEAKISLSNM RIYWLRQRQA 70 80 90 100 110 120 PSSDSHHEFL ALWDSAKGTI HGEEVEQEKI AVFRDASRFI LNLTSVKPED SGIYFCMIVG 130 140 150 160 170 180 SPELTFGKGT QLSVVDFLPT TAQPTKKSTL KKRVCRLPRP ETQKGPLCSP ITLGLLVAGV 190 200 210 220 230 240 LVLLVSLGVA IHLCCRRRRA RLRFMKQPQG EGISGTFVPQ CLHGYYSNTT TSQKLLNPWI LKT
	Isoform 6 (Sbeta1) [UniParc]. Checksum: DBE4D7A3B6A30F58	FASTA	180	20,752
	10 20 30 40 50 60 MRPRLWLLLA AQLTVLHGNS VLQQTPAYIK VQTNKMVMLS CEAKISLSNM RIYWLRQRQA 70 80 90 100 110 120 PSSDSHHEFL ALWDSAKGTI HGEEVEQEKI AVFRDASRFI LNLTSVKPED SGIYFCMIVG 130 140 150 160 170 180 SPELTFGKGT QLSVVDFLPT TAQPTKKSTL KKRVCRLPRP ETQKGRRRRA RLRFMKQFYK
	Isoform 7 (Sbeta4) [UniParc]. Checksum: EE0A2D77A82570D4	FASTA	206	23,633
	10 20 30 40 50 60 MRPRLWLLLA AQLTVLHGNS VLQQTPAYIK VQTNKMVMLS CEAKISLSNM RIYWLRQRQA 70 80 90 100 110 120 PSSDSHHEFL ALWDSAKGTI HGEEVEQEKI AVFRDASRFI LNLTSVKPED SGIYFCMIVG 130 140 150 160 170 180 SPELTFGKGT QLSVVDFLPT TAQPTKKSTL KKRVCRLPRP ETQKDFTNKQ RIGFWCPATK 190 200 RHRSVMSTMW KNERRDTFNP GEFNGC
	Isoform 8 (Sbeta5) [UniParc]. Checksum: 57D7FE949D193C5A	FASTA	198	22,165
	10 20 30 40 50 60 MRPRLWLLLA AQLTVLHGNS VLQQTPAYIK VQTNKMVMLS CEAKISLSNM RIYWLRQRQA 70 80 90 100 110 120 PSSDSHHEFL ALWDSAKGTI HGEEVEQEKI AVFRDASRFI LNLTSVKPED SGIYFCMIVG 130 140 150 160 170 180 SPELTFGKGT QLSVVDFLPT TAQPTKKSTL KKRVCRLPRP ETQKGLKGKV YQGPLSPNAC 190 MDTTAILQPH RSCLTHGS

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"A second subunit of CD8 is expressed in human T cells." Norment A.M., Littman D.R. EMBO J. 7:3433-3439(1988) [PubMed: 3145195] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 1; 2 AND 3). Tissue: T-cell.
[2]	"The human Lyt-3 molecule requires CD8 for cell surface expression." Disanto J.P., Knowles R.W., Flomenberg N. EMBO J. 7:3465-3470(1988) [PubMed: 3145196] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[3]	"A second chain of human CD8 is expressed on peripheral blood lymphocytes." Shiue L., Gorman S.D., Parnes J.R. J. Exp. Med. 168:1993-2005(1988) [PubMed: 3264320] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[4]	"Recent duplication of the two human CD8 beta-chain genes." Nakayama K., Kawachi Y., Tokito S., Minami N., Yamamoto R., Imai T., Gachelin G., Nakauchi H. J. Immunol. 148:1919-1927(1992) [PubMed: 1541829] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] (ISOFORMS 1; 2; 3 AND 4).
[5]	"Generation and annotation of the DNA sequences of human chromosomes 2 and 4." Hillier L.W., Graves T.A., Fulton R.S., Fulton L.A., Pepin K.H., Minx P., Wagner-McPherson C., Layman D., Wylie K., Sekhon M., Becker M.C., Fewell G.A., Delehaunty K.D., Miner T.L., Nash W.E., Kremitzki C., Oddy L., Du H. , Sun H., Bradshaw-Cordum H., Ali J., Carter J., Cordes M., Harris A., Isak A., van Brunt A., Nguyen C., Du F., Courtney L., Kalicki J., Ozersky P., Abbott S., Armstrong J., Belter E.A., Caruso L., Cedroni M., Cotton M., Davidson T., Desai A., Elliott G., Erb T., Fronick C., Gaige T., Haakenson W., Haglund K., Holmes A., Harkins R., Kim K., Kruchowski S.S., Strong C.M., Grewal N., Goyea E., Hou S., Levy A., Martinka S., Mead K., McLellan M.D., Meyer R., Randall-Maher J., Tomlinson C., Dauphin-Kohlberg S., Kozlowicz-Reilly A., Shah N., Swearengen-Shahid S., Snider J., Strong J.T., Thompson J., Yoakum M., Leonard S., Pearman C., Trani L., Radionenko M., Waligorski J.E., Wang C., Rock S.M., Tin-Wollam A.-M., Maupin R., Latreille P., Wendl M.C., Yang S.-P., Pohl C., Wallis J.W., Spieth J., Bieri T.A., Berkowicz N., Nelson J.O., Osborne J., Ding L., Meyer R., Sabo A., Shotland Y., Sinha P., Wohldmann P.E., Cook L.L., Hickenbotham M.T., Eldred J., Williams D., Jones T.A., She X., Ciccarelli F.D., Izaurralde E., Taylor J., Schmutz J., Myers R.M., Cox D.R., Huang X., McPherson J.D., Mardis E.R., Clifton S.W., Warren W.C., Chinwalla A.T., Eddy S.R., Marra M.A., Ovcharenko I., Furey T.S., Miller W., Eichler E.E., Bork P., Suyama M., Torrents D., Waterston R.H., Wilson R.K. Nature 434:724-731(2005) [PubMed: 15815621] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[6]	"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] (ISOFORM 5).
[7]	"Transcriptional diversity at the duplicated human CD8 beta loci." DiSanto J.P., Smith D., de Bruin D., Lacy E., Flomenberg N. Eur. J. Immunol. 23:320-326(1993) [PubMed: 8436166] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 162-210 (ISOFORMS 1; 2; 3; 5; 6; 7 AND 8), ALTERNATIVE SPLICING, TISSUE SPECIFICITY. Tissue: Peripheral blood.
+	Additional computationally mapped references.

Web resources

Wikipedia

CD8 entry

Cross-references

Sequence databases
EMBL GenBank DDBJ	X13444 mRNA. Translation: CAA31795.1. X13445 mRNA. Translation: CAA31796.1. X13446 mRNA. Translation: CAA31797.1. X13452 mRNA. Translation: CAA31803.1. Y00805 mRNA. Translation: CAA68750.1. M36712 mRNA. Translation: AAA35664.1. S87090 , S87068, S87070, S87073, S87081 Genomic DNA. Translation: AAB21669.2. S87087 , S87068, S87070, S87073, S87078, S87081 Genomic DNA. Translation: AAB21670.2. S87083 , S87068, S87070, S87073, S87078, S87081 Genomic DNA. Translation: AAB21671.2. S87083 , S87068, S87070, S87073, S87078, S87081 Genomic DNA. Translation: AAB21672.2. AC111200 Genomic DNA. No translation available. BC100911 mRNA. Translation: AAI00912.1. BC100913 mRNA. Translation: AAI00914.1. BC100914 mRNA. Translation: AAI00915.1. S55731, S55730, S55733 Genomic DNA. Translation: AAD13877.1. Sequence problems.
IPI	IPI00023641. IPI00218643. IPI00218644. IPI00218645. IPI00333756. IPI00969417. IPI00969593. IPI00969609.
PIR	C49050. D46482. E49050. G49050. E46482. S01647. C46482. S01873. B46482. S01874. T01073.
RefSeq	NP_001171571.1. NM_001178100.1. NP_004922.1. NM_004931.4. NP_742099.1. NM_172101.3. NP_742100.1. NM_172102.3. NP_757362.1. NM_172213.3.
UniGene	Hs.405667.
3D structure databases
ProteinModelPortal	P10966.
SMR	P10966. Positions 22-143.
ModBase	Search...
Protein-protein interaction databases
STRING	P10966.
Polymorphism databases
DMDM	116032.
Proteomic databases
PRIDE	P10966.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
Ensembl	ENST00000390655; ENSP00000375070; ENSG00000172116.
GeneID	926.
KEGG	hsa:926.
UCSC	uc002srx.1. human. uc002sry.1. human. uc002srz.1. human.
Organism-specific databases
CTD	926.
GeneCards	GC02M087042.
HGNC	HGNC:1707. CD8B.
HPA	CAB004353.
MIM	186730. gene.
neXtProt	NX_P10966.
PharmGKB	PA26245.
GenAtlas	Search...
Phylogenomic databases
GeneTree	ENSGT00510000048998.
HOVERGEN	HBG105700.
OMA	TRIYWLR.
Enzyme and pathway databases
Pathway_Interaction_DB	cd8tcrdownstreampathway. Downstream signaling in naive CD8+ T cells. il12_2pathway. IL12-mediated signaling events. cd8tcrpathway. TCR signaling in naive CD8+ T cells.
Reactome	REACT_6185. HIV Infection. REACT_6900. Immune System.
Gene expression databases
ArrayExpress	P10966.
Bgee	P10966.
CleanEx	HS_CD8B.
Genevestigator	P10966.
GermOnline	ENSG00000172116. Homo sapiens.
Family and domain databases
InterPro	IPR007110. Ig-like. IPR013783. Ig-like_fold. IPR003599. Ig_sub. IPR013106. Ig_V-set. [Graphical view]
Gene3D	G3DSA:2.60.40.10. Ig-like_fold. 1 hit.
KO	K06459.
Pfam	PF07686. V-set. 1 hit. [Graphical view]
SMART	SM00409. IG. 1 hit. [Graphical view]
PROSITE	PS50835. IG_LIKE. 1 hit. [Graphical view]
ProtoNet	Search...
Other
NextBio	3832.
SOURCE	Search...

Entry information

Entry name

CD8B_HUMAN

Accession

Primary (citable) accession number: P10966
Secondary accession number(s): P14860 , P14861, Q15980, Q496E0, Q496E1, Q9UDB4, Q9UDB5, Q9UDB6, Q9UDB7, Q9UDB8, Q9UDB9, Q9UDC0, Q9UQ55

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 1, 1989
Last sequence update:	July 1, 1989
Last modified:	January 25, 2012
This is version 131 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program

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.