P06681 (CO2_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Complement C2
EC=3.4.21.43

Alternative name(s):
C3/C5 convertase

Cleaved into the following 2 chains:

1. Complement C2b fragment
2. Complement C2a fragment

Gene names

Name:

C2

Organism

Homo sapiens (Human) [Reference proteome]

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Mammalia › Theria › Eutheria › Euarchontoglires › Primates › Haplorrhini › Simiiformes › Catarrhini › Hominoidea › Hominidae › Homininae › Homo

Protein attributes

Sequence length	752 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	Component C2 which is part of the classical pathway of the complement system is cleaved by activated factor C1 into two fragments: C2b and C2a. C2a, a serine protease, then combines with complement factor 4b to generate the C3 or C5 convertase.
Catalytic activity	Selective cleavage of Arg-|-Ser bond in complement component C3 alpha-chain to form C3a and C3b, and Arg-|-Xaa bond in complement component C5 alpha-chain to form C5a and C5b.
Subunit structure	C2a interacts with Schistosoma haematobium TOR (via N-terminal extracellular domain). This results in inhibition of the classical and lectin pathway of complement activation, probably due to interference with binding of C2a to C4b such that C3 convertase cannot be formed. This infers resistance to complement-mediated cell lysis, allowing parasite survival and infection. Ref.11
Subcellular location	Secreted.
Polymorphism	The variant Asp-318 is associated with a reduced risk of age-related macular degeneration (ARMD) [MIM:603075]. ARMD is a multifactorial eye disease and the most common cause of irreversible vision loss in the developed world.
Involvement in disease	Complement component 2 deficiency (C2D) [MIM:217000]: A rare defect of the complement classical pathway associated with the development of autoimmune disorders, mainly systemic lupus erythematosus. Skin and joint manifestations are common and renal disease is relatively rare. Patients with complement component 2 deficiency are also reported to have recurrent invasive infections. Note: The disease is caused by mutations affecting the gene represented in this entry. Ref.19 Ref.20
Miscellaneous	C2 is a major histocompatibility complex class-III protein.
Sequence similarities	Belongs to the peptidase S1 family. Contains 1 peptidase S1 domain. Contains 3 Sushi (CCP/SCR) domains. Contains 1 VWFA domain.

Ontologies

Keywords
Biological process	Complement pathway Immunity Innate immunity
Cellular component	Secreted
Coding sequence diversity	Alternative splicing Polymorphism
Disease	Disease mutation
Domain	Repeat Signal Sushi
Molecular function	Hydrolase Protease Serine protease
PTM	Disulfide bond Glycoprotein
Technical term	3D-structure Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Biological_process	complement activation, classical pathway Traceable author statement Ref.19. Source: ProtInc innate immune response Traceable author statement. Source: Reactome proteolysis Inferred from electronic annotation. Source: UniProtKB-KW regulation of complement activation Traceable author statement. Source: Reactome
Cellular_component	extracellular space Traceable author statement Ref.19. Source: ProtInc
Molecular_function	serine-type endopeptidase activity Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Alternative products

This entry describes 3 isoforms produced by alternative splicing. [Align] [Select]

Isoform 1 (identifier: P06681-1)

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: P06681-2)

The sequence of this isoform differs from the canonical sequence as follows:
     1-147: MGPLMVLFCL...DGETAVCDNG → MRALCIRETCSSELGFSRNWSRRK
     238-328: Missing.

Note: No experimental confirmation available.

Isoform 3 (identifier: P06681-3)

The sequence of this isoform differs from the canonical sequence as follows:
     16-147: Missing.

Note: No experimental confirmation available.

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Signal peptide

1 – 20

20

Ref.9 Ref.11

Chain

21 – 752

732

Complement C2

PRO_0000027610

Chain

21 – 243

223

Complement C2b fragment

PRO_0000027611

Chain

244 – 752

509

Complement C2a fragment

PRO_0000027612

Regions

Domain

22 – 86

65

Sushi 1

Domain

87 – 146

60

Sushi 2

Domain

149 – 206

58

Sushi 3

Domain

254 – 452

199

VWFA

Domain

464 – 744

281

Peptidase S1

Sites

Active site

507

1

Charge relay system By similarity

Active site

561

1

Charge relay system By similarity

Active site

679

1

Charge relay system By similarity

Amino acid modifications

Glycosylation

29

1

N-linked (GlcNAc...) Potential

Glycosylation

112

1

N-linked (GlcNAc...) Ref.16 Ref.17

Glycosylation

290

1

N-linked (GlcNAc...) Potential

Glycosylation

333

1

N-linked (GlcNAc...) Ref.16 Ref.17

Glycosylation

467

1

N-linked (GlcNAc...) Ref.16

Glycosylation

471

1

N-linked (GlcNAc...) Ref.16

Glycosylation

621

1

N-linked (GlcNAc...) Ref.16

Glycosylation

651

1

N-linked (GlcNAc...) Ref.16

Disulfide bond

24 ↔ 64

Ref.18

Disulfide bond

51 ↔ 84

Ref.18

Disulfide bond

89 ↔ 131

Ref.18

Disulfide bond

117 ↔ 144

Ref.18

Disulfide bond

151 ↔ 191

Ref.18

Disulfide bond

177 ↔ 204

Ref.18

Disulfide bond

492 ↔ 508

By similarity

Disulfide bond

675 ↔ 705

By similarity

Natural variations

Alternative sequence

1 – 147

147

MGPLM…VCDNG → MRALCIRETCSSELGFSRNW SRRK in isoform 2.

VSP_043038

Alternative sequence

16 – 147

132

Missing in isoform 3.

VSP_046103

Alternative sequence

238 – 328

91

Missing in isoform 2.

VSP_043039

Natural variant

131

1

C → Y in C2D. Ref.20

VAR_008544

Natural variant

209

1

S → F in C2D. Ref.19
Corresponds to variant rs28934590 [ dbSNP | Ensembl ].

VAR_008545

Natural variant

318

1

E → D. Ref.5 Ref.21
Corresponds to variant rs9332739 [ dbSNP | Ensembl ].

VAR_019158

Natural variant

464

1

G → R in C2D. Ref.19

VAR_008546

Natural variant

533

1

F → L.
Corresponds to variant rs1042664 [ dbSNP | Ensembl ].

VAR_011772

Natural variant

734

1

R → C. Ref.5
Corresponds to variant rs4151648 [ dbSNP | Ensembl ].

VAR_019159

Experimental info

Sequence conflict

30

1

I → L AA sequence Ref.9

Sequence conflict

34

1

T → S AA sequence Ref.9

Sequence conflict

211

1

D → G in BAG62532. Ref.6

Sequence conflict

249

1

R → S AA sequence Ref.9

Sequence conflict

253

1

L → K AA sequence Ref.9

Secondary structure

1

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752

Helix Strand Turn

Details...

Beta strand

34 – 39

6

Beta strand

46 – 50

5

Beta strand

55 – 59

5

Beta strand

61 – 64

4

Beta strand

83 – 86

4

Beta strand

88 – 90

3

Beta strand

98 – 102

5

Beta strand

105 – 108

4

Beta strand

112 – 117

6

Beta strand

122 – 125

4

Beta strand

127 – 131

5

Beta strand

137 – 139

3

Beta strand

143 – 145

3

Beta strand

149 – 151

3

Beta strand

160 – 163

4

Beta strand

172 – 177

6

Beta strand

182 – 185

4

Beta strand

187 – 191

5

Beta strand

197 – 199

3

Beta strand

203 – 205

3

Helix

207 – 211

5

Beta strand

249 – 260

12

Helix

267 – 285

19

Beta strand

291 – 306

16

Helix

311 – 314

4

Helix

316 – 324

9

Helix

328 – 331

4

Helix

339 – 357

19

Beta strand

359 – 361

3

Helix

362 – 365

4

Beta strand

367 – 375

9

Beta strand

381 – 383

3

Helix

386 – 395

10

Helix

403 – 405

3

Beta strand

406 – 416

11

Helix

420 – 426

7

Beta strand

436 – 441

6

Helix

442 – 452

11

Beta strand

470 – 472

3

Helix

474 – 477

4

Beta strand

481 – 485

5

Beta strand

492 – 496

5

Beta strand

498 – 504

7

Helix

506 – 508

3

Helix

515 – 517

3

Beta strand

519 – 522

4

Beta strand

531 – 533

3

Beta strand

535 – 540

6

Turn

546 – 549

4

Helix

550 – 552

3

Beta strand

563 – 569

7

Beta strand

574 – 576

3

Helix

586 – 591

6

Helix

600 – 607

8

Beta strand

610 – 618

9

Beta strand

624 – 630

7

Helix

633 – 640

8

Helix

641 – 644

4

Turn

646 – 648

3

Helix

655 – 657

3

Beta strand

663 – 666

4

Helix

676 – 678

3

Beta strand

682 – 687

6

Beta strand

690 – 701

12

Turn

704 – 707

4

Beta strand

720 – 723

4

Beta strand

727 – 731

5

Helix

732 – 734

3

Helix

736 – 743

8

Turn

744 – 746

3

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 [UniParc]. Last modified December 15, 1998. Version 2. Checksum: 5A96A13E700CF444	FASTA	752	83,268
	10 20 30 40 50 60 MGPLMVLFCL LFLYPGLADS APSCPQNVNI SGGTFTLSHG WAPGSLLTYS CPQGLYPSPA 70 80 90 100 110 120 SRLCKSSGQW QTPGATRSLS KAVCKPVRCP APVSFENGIY TPRLGSYPVG GNVSFECEDG 130 140 150 160 170 180 FILRGSPVRQ CRPNGMWDGE TAVCDNGAGH CPNPGISLGA VRTGFRFGHG DKVRYRCSSN 190 200 210 220 230 240 LVLTGSSERE CQGNGVWSGT EPICRQPYSY DFPEDVAPAL GTSFSHMLGA TNPTQKTKES 250 260 270 280 290 300 LGRKIQIQRS GHLNLYLLLD CSQSVSENDF LIFKESASLM VDRIFSFEIN VSVAIITFAS 310 320 330 340 350 360 EPKVLMSVLN DNSRDMTEVI SSLENANYKD HENGTGTNTY AALNSVYLMM NNQMRLLGME 370 380 390 400 410 420 TMAWQEIRHA IILLTDGKSN MGGSPKTAVD HIREILNINQ KRNDYLDIYA IGVGKLDVDW 430 440 450 460 470 480 RELNELGSKK DGERHAFILQ DTKALHQVFE HMLDVSKLTD TICGVGNMSA NASDQERTPW 490 500 510 520 530 540 HVTIKPKSQE TCRGALISDQ WVLTAAHCFR DGNDHSLWRV NVGDPKSQWG KEFLIEKAVI 550 560 570 580 590 600 SPGFDVFAKK NQGILEFYGD DIALLKLAQK VKMSTHARPI CLPCTMEANL ALRRPQGSTC 610 620 630 640 650 660 RDHENELLNK QSVPAHFVAL NGSKLNINLK MGVEWTSCAE VVSQEKTMFP NLTDVREVVT 670 680 690 700 710 720 DQFLCSGTQE DESPCKGESG GAVFLERRFR FFQVGLVSWG LYNPCLGSAD KNSRKRAPRS 730 740 750 KVPPPRDFHI NLFRMQPWLR QHLGDVLNFL PL
	Isoform 2 [UniParc]. Checksum: DAD9613AAAF483E8	FASTA	538	60,318
	10 20 30 40 50 60 MRALCIRETC SSELGFSRNW SRRKAGHCPN PGISLGAVRT GFRFGHGDKV RYRCSSNLVL 70 80 90 100 110 120 TGSSERECQG NGVWSGTEPI CRQPYSYDFP EDVAPALGTS FSHMLGATNP TQKTKDHENG 130 140 150 160 170 180 TGTNTYAALN SVYLMMNNQM RLLGMETMAW QEIRHAIILL TDGKSNMGGS PKTAVDHIRE 190 200 210 220 230 240 ILNINQKRND YLDIYAIGVG KLDVDWRELN ELGSKKDGER HAFILQDTKA LHQVFEHMLD 250 260 270 280 290 300 VSKLTDTICG VGNMSANASD QERTPWHVTI KPKSQETCRG ALISDQWVLT AAHCFRDGND 310 320 330 340 350 360 HSLWRVNVGD PKSQWGKEFL IEKAVISPGF DVFAKKNQGI LEFYGDDIAL LKLAQKVKMS 370 380 390 400 410 420 THARPICLPC TMEANLALRR PQGSTCRDHE NELLNKQSVP AHFVALNGSK LNINLKMGVE 430 440 450 460 470 480 WTSCAEVVSQ EKTMFPNLTD VREVVTDQFL CSGTQEDESP CKGESGGAVF LERRFRFFQV 490 500 510 520 530 GLVSWGLYNP CLGSADKNSR KRAPRSKVPP PRDFHINLFR MQPWLRQHLG DVLNFLPL
	Isoform 3 [UniParc]. Checksum: FC295E99940BE04D	FASTA	620	69,444
	10 20 30 40 50 60 MGPLMVLFCL LFLYPAGHCP NPGISLGAVR TGFRFGHGDK VRYRCSSNLV LTGSSERECQ 70 80 90 100 110 120 GNGVWSGTEP ICRQPYSYDF PEDVAPALGT SFSHMLGATN PTQKTKESLG RKIQIQRSGH 130 140 150 160 170 180 LNLYLLLDCS QSVSENDFLI FKESASLMVD RIFSFEINVS VAIITFASEP KVLMSVLNDN 190 200 210 220 230 240 SRDMTEVISS LENANYKDHE NGTGTNTYAA LNSVYLMMNN QMRLLGMETM AWQEIRHAII 250 260 270 280 290 300 LLTDGKSNMG GSPKTAVDHI REILNINQKR NDYLDIYAIG VGKLDVDWRE LNELGSKKDG 310 320 330 340 350 360 ERHAFILQDT KALHQVFEHM LDVSKLTDTI CGVGNMSANA SDQERTPWHV TIKPKSQETC 370 380 390 400 410 420 RGALISDQWV LTAAHCFRDG NDHSLWRVNV GDPKSQWGKE FLIEKAVISP GFDVFAKKNQ 430 440 450 460 470 480 GILEFYGDDI ALLKLAQKVK MSTHARPICL PCTMEANLAL RRPQGSTCRD HENELLNKQS 490 500 510 520 530 540 VPAHFVALNG SKLNINLKMG VEWTSCAEVV SQEKTMFPNL TDVREVVTDQ FLCSGTQEDE 550 560 570 580 590 600 SPCKGESGGA VFLERRFRFF QVGLVSWGLY NPCLGSADKN SRKRAPRSKV PPPRDFHINL 610 620 FRMQPWLRQH LGDVLNFLPL

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Primary structure of human complement component C2. Homology to two unrelated protein families." Bentley D.R. Biochem. J. 239:339-345(1986) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). Tissue: Liver.
[2]	"cDNA cloning and expression of human complement component C2." Horiuchi T., Macon K.J., Kidd V.J., Volanakis J.E. J. Immunol. 142:2105-2111(1989) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). Tissue: Liver.
[3]	"Structure of the human C2 gene." Ishii Y., Zhu Z.B., Macon K.J., Volanakis J.E. J. Immunol. 151:170-174(1993) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[4]	"Sequence determination of 300 kilobases of the human class III MHC locus." Rowen L., Dankers C., Baskin D., Faust J., Loretz C., Ahearn M.E., Banta A., Swartzell S., Smith T.M., Spies T., Hood L. Submitted (SEP-1997) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[5]	SeattleSNPs variation discovery resource Submitted (JUL-2003) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], VARIANTS ASP-318 AND CYS-734.
[6]	"Complete sequencing and characterization of 21,243 full-length human cDNAs." Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S. , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S. Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 2 AND 3). Tissue: Kidney and Small intestine.
[7]	"The DNA sequence and analysis of human chromosome 6." Mungall A.J., Palmer S.A., Sims S.K., Edwards C.A., Ashurst J.L., Wilming L., Jones M.C., Horton R., Hunt S.E., Scott C.E., Gilbert J.G.R., Clamp M.E., Bethel G., Milne S., Ainscough R., Almeida J.P., Ambrose K.D., Andrews T.D. , Ashwell R.I.S., Babbage A.K., Bagguley C.L., Bailey J., Banerjee R., Barker D.J., Barlow K.F., Bates K., Beare D.M., Beasley H., Beasley O., Bird C.P., Blakey S.E., Bray-Allen S., Brook J., Brown A.J., Brown J.Y., Burford D.C., Burrill W., Burton J., Carder C., Carter N.P., Chapman J.C., Clark S.Y., Clark G., Clee C.M., Clegg S., Cobley V., Collier R.E., Collins J.E., Colman L.K., Corby N.R., Coville G.J., Culley K.M., Dhami P., Davies J., Dunn M., Earthrowl M.E., Ellington A.E., Evans K.A., Faulkner L., Francis M.D., Frankish A., Frankland J., French L., Garner P., Garnett J., Ghori M.J., Gilby L.M., Gillson C.J., Glithero R.J., Grafham D.V., Grant M., Gribble S., Griffiths C., Griffiths M.N.D., Hall R., Halls K.S., Hammond S., Harley J.L., Hart E.A., Heath P.D., Heathcott R., Holmes S.J., Howden P.J., Howe K.L., Howell G.R., Huckle E., Humphray S.J., Humphries M.D., Hunt A.R., Johnson C.M., Joy A.A., Kay M., Keenan S.J., Kimberley A.M., King A., Laird G.K., Langford C., Lawlor S., Leongamornlert D.A., Leversha M., Lloyd C.R., Lloyd D.M., Loveland J.E., Lovell J., Martin S., Mashreghi-Mohammadi M., Maslen G.L., Matthews L., McCann O.T., McLaren S.J., McLay K., McMurray A., Moore M.J.F., Mullikin J.C., Niblett D., Nickerson T., Novik K.L., Oliver K., Overton-Larty E.K., Parker A., Patel R., Pearce A.V., Peck A.I., Phillimore B.J.C.T., Phillips S., Plumb R.W., Porter K.M., Ramsey Y., Ranby S.A., Rice C.M., Ross M.T., Searle S.M., Sehra H.K., Sheridan E., Skuce C.D., Smith S., Smith M., Spraggon L., Squares S.L., Steward C.A., Sycamore N., Tamlyn-Hall G., Tester J., Theaker A.J., Thomas D.W., Thorpe A., Tracey A., Tromans A., Tubby B., Wall M., Wallis J.M., West A.P., White S.S., Whitehead S.L., Whittaker H., Wild A., Willey D.J., Wilmer T.E., Wood J.M., Wray P.W., Wyatt J.C., Young L., Younger R.M., Bentley D.R., Coulson A., Durbin R.M., Hubbard T., Sulston J.E., Dunham I., Rogers J., Beck S. Nature 425:805-811(2003) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[8]	"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] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1). Tissue: Brain.
[9]	"The purification and properties of the second component of guinea-pig complement." Kerr M.A., Gagnon J. Biochem. J. 205:59-67(1982) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 21-46 AND 244-256.
[10]	"DNA polymorphism of the C2 locus." Bentley D.R., Campbell R.D., Cross S.J. Immunogenetics 22:377-390(1985) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 21-46.
[11]	"A Schistosoma protein, Sh-TOR, is a novel inhibitor of complement which binds human C2." Inal J.M., Sim R.B. FEBS Lett. 470:131-134(2000) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 21-28, INTERACTION WITH SCHISTOSOMA HAEMATOBIUM TOR.
[12]	"Structure and activation of complement components C2 and factor B." Gagnon J. Philos. Trans. R. Soc. Lond., B, Biol. Sci. 306:301-309(1984) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 137-171; 454-466 AND 574-717.
[13]	"The reaction of iodine and thiol-blocking reagents with human complement components C2 and factor B. Purification and N-terminal amino acid sequence of a peptide from C2a containing a free thiol group." Parkes C., Gagnon J., Kerr M.A. Biochem. J. 213:201-209(1983) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 244-269.
[14]	"Isolation of cDNA clones for human complement component C2." Bentley D.R., Porter R.R. Proc. Natl. Acad. Sci. U.S.A. 81:1212-1215(1984) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 588-717 (ISOFORM 1).
[15]	"Cell-specific expression of the human complement protein factor B gene: evidence for the role of two distinct 5'-flanking elements." Wu L.C., Morley B.J., Campbell R.D. Cell 48:331-342(1987) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 694-752.
[16]	"Human plasma N-glycoproteome analysis by immunoaffinity subtraction, hydrazide chemistry, and mass spectrometry." Liu T., Qian W.-J., Gritsenko M.A., Camp D.G. II, Monroe M.E., Moore R.J., Smith R.D. J. Proteome Res. 4:2070-2080(2005) [PubMed] [Europe PMC] [Abstract] Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-112; ASN-333; ASN-467; ASN-471; ASN-621 AND ASN-651, MASS SPECTROMETRY. Tissue: Plasma.
[17]	"Glycoproteomics analysis of human liver tissue by combination of multiple enzyme digestion and hydrazide chemistry." Chen R., Jiang X., Sun D., Han G., Wang F., Ye M., Wang L., Zou H. J. Proteome Res. 8:651-661(2009) [PubMed] [Europe PMC] [Abstract] Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-112 AND ASN-333, MASS SPECTROMETRY. Tissue: Liver.
[18]	"The structure of C2b, a fragment of complement component C2 produced during C3 convertase formation." Krishnan V., Xu Y., Macon K., Volanakis J.E., Narayana S.V. Acta Crystallogr. D 65:266-274(2009) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS) OF 21-243, DISULFIDE BONDS.
[19]	"Type II human complement C2 deficiency. Allele-specific amino acid substitutions (Ser189 --> Phe; Gly444 --> Arg) cause impaired C2 secretion." Wetsel R.A., Kulics J., Lokki M.L., Kiepiela P., Akama H., Johnson C.A., Densen P., Colten H.R. J. Biol. Chem. 271:5824-5831(1996) [PubMed] [Europe PMC] [Abstract] Cited for: VARIANTS C2D PHE-209 AND ARG-464.
[20]	"A novel type II complement C2 deficiency allele in an African-American family." Zhu Z.B., Atkinson T.P., Volanakis J.E. J. Immunol. 161:578-584(1998) [PubMed] [Europe PMC] [Abstract] Cited for: VARIANT C2D TYR-131.
[21]	"Variation in factor B (BF) and complement component 2 (C2) genes is associated with age-related macular degeneration." Gold B., Merriam J.E., Zernant J., Hancox L.S., Taiber A.J., Gehrs K., Cramer K., Neel J., Bergeron J., Barile G.R., Smith R.T., Hageman G.S., Dean M., Allikmets R. Nat. Genet. 38:458-462(2006) [PubMed] [Europe PMC] [Abstract] Cited for: VARIANT ASP-318, INVOLVEMENT IN REDUCED RISK OF ARMD.
+	Additional computationally mapped references.

Web resources

C2base

C2 mutation db

SeattleSNPs

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

X04481 mRNA. Translation: CAA28169.1.
M26301 mRNA. Translation: AAA35614.1.
L09708, L09706, L09707 Genomic DNA. Translation: AAB97607.1.
AF019413 Genomic DNA. Translation: AAB67975.1.
AY349611 Genomic DNA. Translation: AAQ15273.1.
AK298311 mRNA. Translation: BAG60565.1.
AK300892 mRNA. Translation: BAG62532.1.
AL645922 Genomic DNA. No translation available.
AL662834 Genomic DNA. No translation available.
AL662849 Genomic DNA. No translation available.
AL671762 Genomic DNA. No translation available.
AL844853 Genomic DNA. No translation available.
BX005143 Genomic DNA. No translation available.
CR388219 Genomic DNA. No translation available.
CR759782 Genomic DNA. No translation available.
CR759784 Genomic DNA. No translation available.
CR933857 Genomic DNA. No translation available.
BC043484 mRNA. Translation: AAH43484.1.
M15549 Genomic DNA. Translation: AAA59649.1.
M15082 Genomic DNA. Translation: AAA59624.1.

IPI

IPI00303963.
IPI00645500.
IPI01011607.

PIR

C2HU. A25971.

RefSeq

NP_000054.2. NM_000063.4.
NP_001139375.1. NM_001145903.1.
NP_001171534.1. NM_001178063.1.

UniGene

Hs.408903.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
2I6Q	X-ray	2.10	A	244-752	[»]
2I6S	X-ray	2.70	A	244-752	[»]
2ODP	X-ray	1.90	A	244-752	[»]
2ODQ	X-ray	2.30	A	244-752	[»]
3ERB	X-ray	1.80	A	21-243	[»]

ProteinModelPortal

P06681.

ModBase

Search...

Protein-protein interaction databases

IntAct

P06681. 1 interaction.

STRING

9606.ENSP00000372853.

Protein family/group databases

MEROPS

S01.194.

PTM databases

PhosphoSite

P06681.

Polymorphism databases

DMDM

3915642.

Proteomic databases

PaxDb

P06681.

PRIDE

P06681.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

Ensembl

ENST00000299367; ENSP00000299367; ENSG00000166278.
ENST00000375510; ENSP00000364660; ENSG00000204364.
ENST00000383362; ENSP00000372853; ENSG00000206372.
ENST00000411803; ENSP00000402278; ENSG00000235696.
ENST00000413548; ENSP00000407961; ENSG00000231543.
ENST00000416252; ENSP00000405800; ENSG00000235017.
ENST00000442278; ENSP00000395683; ENSG00000166278.
ENST00000448206; ENSP00000392835; ENSG00000226560.
ENST00000452323; ENSP00000392322; ENSG00000166278.
ENST00000546628; ENSP00000448699; ENSG00000231543.
ENST00000548543; ENSP00000448710; ENSG00000206372.
ENST00000548973; ENSP00000446728; ENSG00000206372.
ENST00000548995; ENSP00000449286; ENSG00000204364.
ENST00000549972; ENSP00000447632; ENSG00000235696.
ENST00000550414; ENSP00000448730; ENSG00000226560.
ENST00000550682; ENSP00000446639; ENSG00000231543.
ENST00000551081; ENSP00000450387; ENSG00000235017.
ENST00000551648; ENSP00000449715; ENSG00000226560.
ENST00000553073; ENSP00000446600; ENSG00000235017.

GeneID

717.

KEGG

hsa:717.

UCSC

uc003nyf.3. human.

Organism-specific databases

CTD

717.

GeneCards

GC06P031865.

HGNC

HGNC:1248. C2.

HPA

CAB016775.

MIM

217000. phenotype.
603075. phenotype.
613927. gene.

neXtProt

NX_P06681.

Orphanet

169147. Immunodeficiency due to an early component of complement deficiency.

PharmGKB

PA25637.

GenAtlas

Search...

Phylogenomic databases

eggNOG

NOG306397.

HOGENOM

HOG000038034.

HOVERGEN

HBG002567.

InParanoid

P06681.

KO

K01332.

OMA

RDMTEVI.

OrthoDB

EOG45DWP0.

Enzyme and pathway databases

Reactome

REACT_6900. Immune System.

Gene expression databases

ArrayExpress

P06681.

Bgee

P06681.

CleanEx

HS_C2.

Genevestigator

P06681.

GermOnline

ENSG00000204364. Homo sapiens.

Family and domain databases

InterPro

IPR011360. Compl_C2_B.
IPR001254. Peptidase_S1.
IPR018114. Peptidase_S1_AS.
IPR001314. Peptidase_S1A.
IPR000436. Sushi_SCR_CCP.
IPR009003. Trypsin-like_Pept_dom.
IPR002035. VWF_A.
[Graphical view]

Pfam

PF00084. Sushi. 2 hits.
PF00089. Trypsin. 1 hit.
PF00092. VWA. 1 hit.
[Graphical view]

PIRSF

PIRSF001154. Compl_C2_B. 1 hit.

PRINTS

PR00722. CHYMOTRYPSIN.

SMART

SM00032. CCP. 1 hit.
SM00020. Tryp_SPc. 1 hit.
SM00327. VWA. 1 hit.
[Graphical view]

SUPFAM

SSF57535. Complement_control_module. 1 hit.
SSF50494. Pept_Ser_Cys. 1 hit.

PROSITE

PS50923. SUSHI. 3 hits.
PS50240. TRYPSIN_DOM. 1 hit.
PS00134. TRYPSIN_HIS. 1 hit.
PS00135. TRYPSIN_SER. 1 hit.
PS50234. VWFA. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

ChiTaRS

C2. human.

EvolutionaryTrace

P06681.

GenomeRNAi

717.

NextBio

2918.

PMAP-CutDB

P06681.

SOURCE

Search...

Entry information

Entry name

CO2_HUMAN

Accession

Primary (citable) accession number: P06681
Secondary accession number(s): B4DPF3 , B4DV20, E9PFN7, O19694, Q13904

Entry history

Integrated into UniProtKB/Swiss-Prot:	January 1, 1988
Last sequence update:	December 15, 1998
Last modified:	May 1, 2013
This is version 159 of the entry and version 2 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.