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C2a [extracellular region]
Stable Identifier
R-HSA-166780
Type
Protein [EntityWithAccessionedSequence]
Species
Homo sapiens
Compartment
extracellular region
Synonyms
C2(244-752), Complement factor 2a
Icon
Locations in the PathwayBrowser
Expand all
Immune System (Homo sapiens)
Innate Immune System (Homo sapiens)
Complement cascade (Homo sapiens)
Activation of C3 and C5 (Homo sapiens)
Activation of C5 (Homo sapiens)
C5 convertases [plasma membrane] (Homo sapiens)
C4b:C2a:C3b [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Cleavage of C3 by C3 convertases (Homo sapiens)
C3 convertases [plasma membrane] (Homo sapiens)
C4b:C2a:C3b [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Formation of classic pathway C5 convertase (Homo sapiens)
C4b:C2a:C3b [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Initial triggering of complement (Homo sapiens)
Conversion of C2 into C2a and C2b (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Formation of Classical C3 convertase (C4b:C2a complex) (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Regulation of Complement cascade (Homo sapiens)
C3 convertases spontaneously dissociate (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
C3 convertases [plasma membrane] (Homo sapiens)
C4b:C2a:C3b [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
C4b binding protein binds C4bC2a (Homo sapiens)
C4 binding protein:C4bC2a [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
C4b binding protein displaces C2a (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
C4 binding protein:C4bC2a [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
CD55 (DAF) binds C3bBb, C4bC2a (Homo sapiens)
C4bC2a, C3bBb [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
CD55:C3 convertase complexes [plasma membrane] (Homo sapiens)
CD55:C4bC2a [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
CD55 (DAF) promotes C3bBb/C4bC2a dissociation (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
CD55:C3 convertase complexes [plasma membrane] (Homo sapiens)
CD55:C4bC2a [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
CR1 binds C3bBb/C4bC2a (Homo sapiens)
C4bC2a, C3bBb [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
CR1:C3bBb, C4bC2a complexes [plasma membrane] (Homo sapiens)
CR1:C4bC2a [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
Displacement of C2a/Bb by CR1 (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
CR1:C3bBb, C4bC2a complexes [plasma membrane] (Homo sapiens)
CR1:C4bC2a [plasma membrane] (Homo sapiens)
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
C2a [extracellular region] (Homo sapiens)
External Reference Information
External Reference
UniProt:P06681 C2
Gene Names
C2
Chain
signal peptide:1-20, chain:21-752, chain:21-243, chain:244-752
Reference Genes
BioGPS Gene:717 C2
COSMIC (genes):C2 C2
CTD Gene:717 C2
dbSNP Gene:717 C2
ENSEMBL:ENSG00000166278 C2
HGNC:1248 C2
KEGG:hsa:717 C2
Monarch:717 C2
NCBI Gene:717 C2
OMIM:613927 C2
UCSC:P06681 C2
Reference Transcript
RefSeq:NM_001178063.2 C2
RefSeq:NM_001145903.2 C2
RefSeq:NM_000063.5 C2
Other Identifiers
11717045_a_at
11749355_a_at
11761555_at
11762671_at
1554533_3p_at
1554533_PM_at
1554533_at
17006911
17033493
17040902
203052_PM_at
203052_at
2902805
2902808
2902809
2902810
2902811
2902812
2902813
2902814
2902816
2902817
2902818
2902819
2902820
2902821
2902822
2902823
2902824
2902825
2902826
2902827
2902828
2902829
2902830
2902831
2902832
2902833
2902834
2902835
2902836
2902837
2902845
2902846
2902847
2902848
2902849
2902850
2902851
2902852
33374_at
717
75259_at
8118324
8178095
8179331
A_14_P109173
A_14_P123282
A_23_P133916
A_23_P433865
A_32_P162183
A_32_P162187
A_33_P3404601
GE60490
GO:0002376
GO:0003824
GO:0004252
GO:0005515
GO:0005576
GO:0005601
GO:0005615
GO:0006508
GO:0006956
GO:0006958
GO:0007584
GO:0008236
GO:0009617
GO:0016787
GO:0032496
GO:0043226
GO:0045087
GO:0046872
GO:0070062
GO:0097066
GO:0098542
GO:0140096
GO:2000427
HMNXSV003000659
HMNXSV003031492
Hs2.146777.1.S1_3p_x_at
ILMN_1710740
L09708_at
PH_hs_0000303
TC06004076.hg
TC6_cox_hap2000244.hg
TC6_dbb_hap3000221.hg
TC6_mann_hap4000195.hg
TC6_mcf_hap5000212.hg
TC6_qbl_hap6000224.hg
TC6_ssto_hap7000198.hg
g4557382_3p_at
p33713
Participates
as an output of
C4b binding protein displaces C2a (Homo sapiens)
C3 convertases spontaneously dissociate (Homo sapiens)
CD55 (DAF) promotes C3bBb/C4bC2a dissociation (Homo sapiens)
Displacement of C2a/Bb by CR1 (Homo sapiens)
Conversion of C2 into C2a and C2b (Homo sapiens)
as an input of
Formation of Classical C3 convertase (C4b:C2a complex) (Homo sapiens)
as a component of
Cell surface:C4b:C2a [plasma membrane] (Homo sapiens)
Other forms of this molecule
C2 [extracellular region]
C2b [extracellular region]
Inferred To
C2 [extracellular region]
(Canis familiaris)
C2 [extracellular region]
(Rattus norvegicus)
C2 [extracellular region]
(Sus scrofa)
cfb [extracellular region]
(Xenopus tropicalis)
cfbl [extracellular region]
(Danio rerio)
C2a [extracellular region]
(Bos taurus)
C2a [extracellular region]
(Gallus gallus)
C2a [extracellular region]
(Mus musculus)
Homologues of C2a [extracellular region]
(Danio rerio)
Homologues of C2a [extracellular region]
(Xenopus tropicalis)
bfb [extracellular region]
(Danio rerio)
c2 [extracellular region]
(Xenopus tropicalis)
Cross References
RefSeq
NP_001139375.1
,
NP_001171534.1
,
NP_000054.2
OpenTargets
ENSG00000166278
ENSEMBL
ENSP00000395683
,
ENSP00000449715
,
ENSP00000364660
,
ENSP00000299367
,
ENSP00000392835
,
ENSP00000480739
,
ENSP00000447632
,
ENSP00000482616
,
ENST00000548973
,
ENST00000550682
,
ENSP00000446728
,
ENST00000621558
,
ENST00000442278
,
ENSP00000449286
,
ENST00000618254
,
ENSP00000450387
,
ENST00000452323
,
ENST00000375510
,
ENST00000615380
,
ENSP00000481651
,
ENSP00000405800
,
ENSP00000483231
,
ENSP00000402278
,
ENST00000549972
,
ENSP00000407961
,
ENST00000551648
,
ENST00000299367
,
ENST00000548995
,
ENSP00000446639
,
ENST00000383362
,
ENST00000612228
,
ENST00000448206
,
ENSP00000392322
,
ENST00000413548
,
ENSP00000372853
,
ENST00000416252
,
ENST00000551081
,
ENST00000411803
HPA
ENSG00000166278-C2
PRO
P06681
Pharos - Targets
P06681
Orphanet
C2
PDB
2ODP
,
8ACI
,
2ODQ
,
3ERB
,
2I6S
,
2I6Q
,
8ACF
Interactors (9)
Accession
#Entities
Entities
Confidence Score
Evidence (IntAct)
UniProt:Q15125 EBP
1
EBP [endoplasmic reticulum membrane]
(R-HSA-195697)
0.556
3
UniProt:Q14973 SLC10A1
1
SLC10A1 [plasma membrane]
(R-HSA-194116)
0.556
3
UniProt:Q9NQQ7-3 Q9NQQ73
0.556
3
UniProt:Q9BY50 SEC11C
1
SEC11C [endoplasmic reticulum membrane]
(R-HSA-265065)
0.556
5
UniProt:P15941-11 MUC1
0.556
3
UniProt:O43889-2 CREB3
0.556
3
UniProt:Q9Y282 ERGI3
0.556
3
UniProt:Q5JX71 F209A
0.556
3
UniProt:P27105 STOM
4
STOM [azurophil granule membrane]
(R-HSA-6800997)
STOM [plasma membrane]
(R-HSA-6806258)
STOM [specific granule membrane]
(R-HSA-6799569)
STOM [tertiary granule membrane]
(R-HSA-6800960)
0.556
3
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