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Protein

Complement C1q subcomponent subunit B

Gene

C1QB

Organism
Bos taurus (Bovine)
Status
Reviewed-Annotation score: -Experimental evidence at protein leveli

Functioni

C1q associates with the proenzymes C1r and C1s to yield C1, the first component of the serum complement system. The collagen-like regions of C1q interact with the Ca2+-dependent C1r2C1s2 proenzyme complex, and efficient activation of C1 takes place on interaction of the globular heads of C1q with the Fc regions of IgG or IgM antibody present in immune complexes (By similarity).By similarity

GO - Molecular functioni

GO - Biological processi

Keywordsi

Biological processComplement pathway, Immunity, Innate immunity

Enzyme and pathway databases

ReactomeiR-BTA-166663 Initial triggering of complement
R-BTA-173623 Classical antibody-mediated complement activation
R-BTA-977606 Regulation of Complement cascade

Names & Taxonomyi

Protein namesi
Recommended name:
Complement C1q subcomponent subunit B
Gene namesi
Name:C1QB
OrganismiBos taurus (Bovine)
Taxonomic identifieri9913 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaLaurasiatheriaCetartiodactylaRuminantiaPecoraBovidaeBovinaeBos
Proteomesi
  • UP000009136 Componenti: Chromosome 2

Organism-specific databases

VGNCiVGNC:26617 C1QB

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; Source: COMPARTMENTS

Keywords - Cellular componenti

Secreted

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Signal peptidei1 – 22Sequence analysisAdd BLAST22
ChainiPRO_000028613523 – 247Complement C1q subcomponent subunit BAdd BLAST225

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei23Pyrrolidone carboxylic acidBy similarity1
Disulfide bondi26Interchain (with C-26 in chain A)By similarity
Modified residuei294-hydroxyprolineBy similarity1
Modified residuei324-hydroxyprolineBy similarity1
Modified residuei354-hydroxyprolineBy similarity1
Modified residuei474-hydroxyprolineBy similarity1
Modified residuei504-hydroxyprolineBy similarity1
Modified residuei535-hydroxylysineBy similarity1
Modified residuei565-hydroxylysineBy similarity1
Modified residuei594-hydroxyprolineBy similarity1
Modified residuei715-hydroxylysineBy similarity1
Modified residuei774-hydroxyprolineBy similarity1
Modified residuei804-hydroxyprolineBy similarity1
Modified residuei865-hydroxylysineBy similarity1
Modified residuei925-hydroxylysineBy similarity1
Modified residuei954-hydroxyprolineBy similarity1
Modified residuei984-hydroxyprolineBy similarity1
Modified residuei1045-hydroxylysineBy similarity1

Post-translational modificationi

Hydroxylated on lysine and proline residues. Hydroxylated lysine residues can be glycosylated. Bovine C1Q contains up to 66.3 hydroxylysine-galactosylglucose residues. Total percentage hydroxylysine residues glycosylated is 92.0%. Contains no hydroxylysine-monosaccharides.1 Publication

Keywords - PTMi

Disulfide bond, Glycoprotein, Hydroxylation, Pyrrolidone carboxylic acid

Proteomic databases

PaxDbiQ2KIV9
PRIDEiQ2KIV9

Expressioni

Gene expression databases

BgeeiENSBTAG00000011196

Interactioni

Subunit structurei

C1 is a calcium-dependent trimolecular complex of C1q, c1r and C1s in the molar ration of 1:2:2. C1q subcomponent is composed of nine subunits, six of which are disulfide-linked dimers of the A and B chains, and three of which are disulfide-linked dimers of the C chain (By similarity).By similarity

GO - Molecular functioni

Protein-protein interaction databases

STRINGi9913.ENSBTAP00000014871

Structurei

3D structure databases

ProteinModelPortaliQ2KIV9
SMRiQ2KIV9
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini39 – 98Collagen-likeAdd BLAST60
Domaini111 – 247C1qPROSITE-ProRule annotationAdd BLAST137

Keywords - Domaini

Collagen, Repeat, Signal

Phylogenomic databases

eggNOGiENOG410IWVM Eukaryota
ENOG4111MQB LUCA
GeneTreeiENSGT00760000118830
HOGENOMiHOG000085653
HOVERGENiHBG108220
InParanoidiQ2KIV9
KOiK03987
OMAiCDYAYNT
OrthoDBiEOG091G0L3Y
TreeFamiTF329591

Family and domain databases

Gene3Di2.60.120.40, 1 hit
InterProiView protein in InterPro
IPR001073 C1q_dom
IPR008160 Collagen
IPR037573 Complement_C1qB
IPR008983 Tumour_necrosis_fac-like_dom
PANTHERiPTHR44403:SF2 PTHR44403:SF2, 1 hit
PfamiView protein in Pfam
PF00386 C1q, 1 hit
PF01391 Collagen, 1 hit
PRINTSiPR00007 COMPLEMNTC1Q
SMARTiView protein in SMART
SM00110 C1Q, 1 hit
SUPFAMiSSF49842 SSF49842, 1 hit
PROSITEiView protein in PROSITE
PS50871 C1Q, 1 hit

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

Q2KIV9-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MKTPRGSVLV LLLLNLLRVS WAQSNCIRPS IPGIPGIPGK PGSDGKPGTP
60 70 80 90 100
GTKGEKGLPG LVSHLNENGE KGDPGFPGMP GKVGPKGPIG PKGVPGPPGV
110 120 130 140 150
RGPKGESGDY KATQKIAFSA SRTINHHQRQ GQPIRFDHVI TNANENYQAR
160 170 180 190 200
SSKFTCKVPG LYFFTYHASS RGQLCVDLMR GRAEPQKVVT FCDYVQNTFQ
210 220 230 240
VTTGSIVLKL EKDETVFLQA TEKNALVGIE GANSIFSGFM LFPDTEA
Length:247
Mass (Da):26,399
Last modified:March 7, 2006 - v1
Checksum:i4C2CDCFF75A433B0
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
BC112490 mRNA Translation: AAI12491.1
RefSeqiNP_001040064.1, NM_001046599.2
XP_010800915.1, XM_010802613.1
UniGeneiBt.20164

Genome annotation databases

EnsembliENSBTAT00000014871; ENSBTAP00000014871; ENSBTAG00000011196
GeneIDi617435
KEGGibta:617435

Similar proteinsi

Entry informationi

Entry nameiC1QB_BOVIN
AccessioniPrimary (citable) accession number: Q2KIV9
Entry historyiIntegrated into UniProtKB/Swiss-Prot: May 1, 2007
Last sequence update: March 7, 2006
Last modified: May 23, 2018
This is version 89 of the entry and version 1 of the sequence. See complete history.
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

Complete proteome, Reference proteome

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