Reviewed, UniProtKB/Swiss-Prot Q69DK8 (C1S_PIG)

Names and origin

Protein names	Recommended name:     Complement C1s subcomponent     EC=3.4.21.42 Alternative name(s):     C1 esterase Cleaved into the following 2 chains:     1- Recommended name:             Complement C1s subcomponent heavy chain     2- Recommended name:             Complement C1s subcomponent light chain
Organism	Sus scrofa (Pig)
Taxonomic identifier	9823 [NCBI]
Taxonomic lineage	Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Laurasiatheria › Cetartiodactyla › Suina › Suidae › Sus

Protein attributes

Sequence length	687 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at transcript level.

General annotation (Comments)

Function	C1s B chain is a serine protease that combines with C1q and C1s to form C1, the first component of the classical pathway of the complement system. C1r activates C1s so that it can, in turn, activate C2 and C4 By similarity.
Catalytic activity	Cleavage of Arg-|-Ala bond in complement component C4 to form C4a and C4b, and Lys(or Arg)-|-Lys bond in complement component C2 to form C2a and C2b: the 'classical' pathway C3 convertase.
Enzyme regulation	Inhibited by SERPING1 By similarity.
Subunit structure	C1 is a calcium-dependent trimolecular complex of C1q, C1r and C1s in the molar ration of 1:2:2. Activated C1s is an disulfide-linked heterodimer of a heavy chain and a light chain By similarity.
Post-translational modification	The iron and 2-oxoglutarate dependent 3-hydroxylation of aspartate and asparagine is (R) stereospecific within EGF domains By similarity.
Sequence similarities	Belongs to the peptidase S1 family. Contains 2 CUB domains. Contains 1 EGF-like domain. Contains 1 peptidase S1 domain. Contains 2 Sushi (CCP/SCR) domains.

Ontologies

Keywords
Biological process	Complement pathway Immune response Innate immunity
Domain	EGF-like domain Repeat Signal Sushi
Ligand	Calcium Metal-binding
Molecular function	Hydrolase Protease Serine protease
PTM	Disulfide bond Glycoprotein Hydroxylation
Gene Ontology (GO)
Biological process	complement activation, classical pathway Inferred from electronic annotation. Source: UniProtKB-KW innate immune response Inferred from electronic annotation. Source: UniProtKB-KW proteolysis Inferred from electronic annotation. Source: InterPro
Molecular function	calcium ion binding Inferred from electronic annotation. Source: UniProtKB-KW serine-type endopeptidase 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
	Signal peptide	1 – 15	15	By similarity
	Chain	16 – 687	672	Complement C1s subcomponent		PRO_0000042199
	Chain	16 – 437	422	Complement C1s subcomponent heavy chain By similarity		PRO_0000042200
	Chain	438 – 687	250	Complement C1s subcomponent light chain By similarity		PRO_0000042201
Regions
	Domain	16 – 130	115	CUB 1
	Domain	131 – 172	42	EGF-like; calcium-binding Potential
	Domain	175 – 290	116	CUB 2
	Domain	292 – 356	65	Sushi 1
	Domain	357 – 423	67	Sushi 2
	Domain	438 – 679	242	Peptidase S1
Sites
	Active site	475	1	Charge relay system By similarity
	Active site	528	1	Charge relay system By similarity
	Active site	630	1	Charge relay system By similarity
	Metal binding	60	1	Calcium By similarity
	Metal binding	68	1	Calcium By similarity
	Metal binding	113	1	Calcium By similarity
	Metal binding	131	1	Calcium By similarity
	Metal binding	132	1	Calcium; via carbonyl oxygen By similarity
	Metal binding	134	1	Calcium By similarity
	Metal binding	149	1	Calcium By similarity
	Metal binding	150	1	Calcium; via carbonyl oxygen By similarity
	Metal binding	153	1	Calcium; via carbonyl oxygen By similarity
Amino acid modifications
	Modified residue	149	1	(3R)-3-hydroxyasparagine By similarity
	Glycosylation	174	1	N-linked (GlcNAc...) Potential
	Glycosylation	406	1	N-linked (GlcNAc...) Potential
	Disulfide bond	65 ↔ 83		By similarity
	Disulfide bond	135 ↔ 147		By similarity
	Disulfide bond	143 ↔ 156		By similarity
	Disulfide bond	158 ↔ 171		By similarity
	Disulfide bond	175 ↔ 202		By similarity
	Disulfide bond	234 ↔ 251		By similarity
	Disulfide bond	294 ↔ 341		By similarity
	Disulfide bond	321 ↔ 354		By similarity
	Disulfide bond	359 ↔ 403		By similarity
	Disulfide bond	386 ↔ 421		By similarity
	Disulfide bond	425 ↔ 548		Interchain (between heavy and light chains) By similarity
	Disulfide bond	594 ↔ 617		By similarity
	Disulfide bond	626 ↔ 658		By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q69DK8-1 [UniParc]. Last modified September 13, 2004. Version 1. Checksum: 755C3CAEE06D2C90	FASTA	687	76,101
	10 20 30 40 50 60 MWCIVLLSLL AWVDAEPTMY GEILSPNYPQ AYPNEVEKSW DIEVPEGYGI HLYFTHLDIE 70 80 90 100 110 120 LSENCAYDSV QIKSGGREEG KLCGQKTSKN PKSAVVEEFQ VPYNKLQVIF TSDFSNEERF 130 140 150 160 170 180 TGFAAYYVAV DVNECTDFAD SPCSHFCNNY IGGYFCSCPP EYFLHEDKKN CGVNCSGDVF 190 200 210 220 230 240 TTLIGEVASP NYPNPYPENS RCDYQILLEE GFQVVVTMRR EDFDVEPADS GGHCPDSLIF 250 260 270 280 290 300 VAGNQQFGPY CGNGFPGPLT IETKSNALNI IFQTDETEQK KGWKFRYHGD PIPCPKEVTA 310 320 330 340 350 360 NSFWEPEKAK YVFKDVVKIT CLDGFEVVQG TVGSTSFYST CQSNGKWSNS KLRCQPVDCG 370 380 390 400 410 420 SPEPIPHGKV EDPEHTLFGS VTRYSCEQPY YYMETDGSEE YRCAGNGSWV NELLGAELPK 430 440 450 460 470 480 CVPVCGIPSE PFKGMQRIFG GIITKIESFP WQVFFQNPRA GGALIDEQWV LTAAHVVEGN 490 500 510 520 530 540 REPVMYVGSS SVVTSHLANG QMLTAERVFI HPGWEEQDAS ERKNFDNDIA LVRLKDPVKM 550 560 570 580 590 600 GPTVSPICLP GTSSDYDPSV GDLGLISGWG RTNTKDHVVK LRGAKLPVAP SDKCQEIKGT 610 620 630 640 650 660 NPRIGTSSFV FTDNMICAGG RGVDSCNGDS GGAFAMQVPN EETPKFYVAG LVSWGPQCGT 670 680 YGIYTRVKNY IDWIRETMQQ NSAPSVD

References

[1]	"Molecular analysis of soluble porcine complement component genes." Trakooljul N., Ponsuksili S., Schellander K., Wimmers K. Submitted (JUL-2003) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA].

Cross-references

Sequence databases
EMBLGenBankDDBJ	AY349426 mRNA. Translation: AAR20894.1.
RefSeq	NP_001005349.1.
UniGene	Ssc.1177
3D structure databases
SMR	Q69DK8. Positions 18-174, 357-682.
ModBase	Search...
Genome annotation databases
GeneID	397274.
KEGG	ssc:397274.
Phylogenomic databases
HOVERGEN	Q69DK8.
Enzyme and pathway databases
BRENDA	3.4.21.42. 249.
Family and domain databases
InterPro	IPR016060. Complement_control_module. IPR000859. CUB. IPR006209. EGF. IPR013032. EGF-like_reg_CS. IPR000152. EGF-type_Asp/Asn_hydroxyl_CS. IPR000742. EGF_3. IPR001881. EGF_Ca_bd. IPR018097. EGF_Ca_bd_CS. IPR018114. Peptidase_S1/S6_AS. IPR001254. Peptidase_S1_S6. IPR001314. Peptidase_S1A. IPR000436. Sushi_SCR_CCP. [Graphical view]
Gene3D	G3DSA:2.10.70.10. Complement_control_module. 1 hit. G3DSA:2.60.120.290. CUB. 2 hits.
Pfam	PF00431. CUB. 2 hits. PF00008. EGF. 1 hit. PF00084. Sushi. 2 hits. PF00089. Trypsin. 1 hit. [Graphical view]
PRINTS	PR00722. CHYMOTRYPSIN.
SMART	SM00032. CCP. 2 hits. SM00042. CUB. 2 hits. SM00179. EGF_CA. 1 hit. SM00020. Tryp_SPc. 1 hit. [Graphical view]
PROSITE	PS00010. ASX_HYDROXYL. 1 hit. PS01180. CUB. 2 hits. PS00022. EGF_1. False negative. PS01186. EGF_2. False negative. PS50026. EGF_3. 1 hit. PS01187. EGF_CA. 1 hit. PS50923. SUSHI. 2 hits. PS50240. TRYPSIN_DOM. 1 hit. PS00134. TRYPSIN_HIS. False negative. PS00135. TRYPSIN_SER. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

C1S_PIG

Accession

Primary (citable) accession number: Q69DK8

Entry history

Integrated into UniProtKB/Swiss-Prot:	September 27, 2005
Last sequence update:	September 13, 2004
Last modified:	June 16, 2009
This is version 37 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)