Reviewed, UniProtKB/Swiss-Prot Q5R5A4 (CFAI_PONAB)

Names and origin

Protein names

Recommended name:
    Complement factor I
    EC=3.4.21.45
Alternative name(s):
    C3B/C4B inactivator
Cleaved into the following 2 chains:
    1- Recommended name:
            Complement factor I heavy chain
    2- Recommended name:
            Complement factor I light chain

Gene names

Name:

CFI

Organism

Pongo abelii (Sumatran orangutan)

Taxonomic identifier

9601 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Pongo

Protein attributes

Sequence length	583 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	Responsible for cleaving the alpha-chains of C4b and C3b in the presence of the cofactors C4-binding protein and factor H respectively By similarity.
Catalytic activity	Inactivates complement subcomponents C3b, iC3b and C4b by proteolytic cleavage.
Subunit structure	Heterodimer of a light and heavy chains linked by disulfide bonds By similarity.
Subcellular location	Secreted › extracellular space.
Tissue specificity	Plasma.
Sequence similarities	Belongs to the peptidase S1 family. Contains 2 LDL-receptor class A domains. Contains 1 peptidase S1 domain. Contains 1 SRCR domain.

Ontologies

Keywords
Biological process	Complement pathway Immune response Innate immunity
Cellular component	Secreted
Domain	Repeat Signal
Molecular function	Hydrolase Protease Serine protease
PTM	Cleavage on pair of basic residues Disulfide bond Glycoprotein
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
Cellular component	extracellular space Inferred from electronic annotation. Source: UniProtKB-SubCell membrane Inferred from electronic annotation. Source: InterPro
Molecular function	scavenger receptor activity Inferred from electronic annotation. Source: InterPro 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 – 18	18	By similarity
	Chain	19 – 583	565	Complement factor I		PRO_0000285861
	Chain	19 – 335	317	Complement factor I heavy chain		PRO_0000285862
	Chain	340 – 583	244	Complement factor I light chain		PRO_0000285863
Regions
	Domain	114 – 212	99	SRCR
	Domain	213 – 257	45	LDL-receptor class A 1
	Domain	258 – 294	37	LDL-receptor class A 2
	Domain	340 – 574	235	Peptidase S1
Sites
	Active site	380	1	Charge relay system By similarity
	Active site	429	1	Charge relay system By similarity
	Active site	525	1	Charge relay system By similarity
Amino acid modifications
	Glycosylation	70	1	N-linked (GlcNAc...) Potential
	Glycosylation	103	1	N-linked (GlcNAc...) Potential
	Glycosylation	173	1	N-linked (GlcNAc...) Potential
	Glycosylation	177	1	N-linked (GlcNAc...) Potential
	Glycosylation	464	1	N-linked (GlcNAc...) Potential
	Glycosylation	494	1	N-linked (GlcNAc...) Potential
	Glycosylation	536	1	N-linked (GlcNAc...) Potential
	Disulfide bond	154 ↔ 214		By similarity
	Disulfide bond	186 ↔ 196		By similarity
	Disulfide bond	229 ↔ 247		By similarity
	Disulfide bond	241 ↔ 256		By similarity
	Disulfide bond	259 ↔ 271		By similarity
	Disulfide bond	266 ↔ 284		By similarity
	Disulfide bond	278 ↔ 293		By similarity
	Disulfide bond	365 ↔ 381		By similarity
	Disulfide bond	467 ↔ 531		By similarity
	Disulfide bond	495 ↔ 510		By similarity
	Disulfide bond	521 ↔ 550		By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q5R5A4-1 [UniParc]. Last modified December 21, 2004. Version 1. Checksum: 8A390600223498AA	FASTA	583	65,620
	10 20 30 40 50 60 MKLLHVFLLF LCFHLSFCKV TYTSQEDLVE KKCLAKKHTH LSCNKVFCQP WQICIEGTCI 70 80 90 100 110 120 CKLPYQCPKN GTTVCATNGR SFPTYCQQKS LECLRPGTKF LNNGTCTAEG KFSVSLKHGN 130 140 150 160 170 180 TDSEGIVEVK LVDQDKTMFI CKSSWSMREA NVACLDLGFQ QGADTQRRFK LSNLSINSTE 190 200 210 220 230 240 CLHVHCRGLE TSLAECTFTK RRTMGYQDLA DVVCYTQKAD SPTNDFFQCV NGKYISQMKA 250 260 270 280 290 300 CDGINDCGDQ SDELCCKACQ GKSFHCKSGV CIPSQYRCNG EVDCITGEDE VGCEGFASVA 310 320 330 340 350 360 QEETEILTAD MDAERRRIKS LLPKLSCGVK NRRHIRRKRI VGGKRAQLGD LPWQVGIKDA 370 380 390 400 410 420 SGITCGGIYI GGCWILTAAH CLRASKTHHY QIWTTVVDWI HPDRKRIVIE YVDRIIFHEN 430 440 450 460 470 480 YNAGTYQNDI ALMEMKKDGN KKDCELPRSI PACVPWSPYL FQPNDTCIVS GWGREKDNEK 490 500 510 520 530 540 VFSLQWGEVK LISNCSKFYG NRFYEKEMEC AGTYDGSIDA CKGDSGGPLV CMDANNVTYV 550 560 570 580 WGVVSWGENC GKPEFPGVYT KVANYFDWIS YHVGRPFISQ YNV

References

[1]	The German cDNA consortium Submitted (NOV-2004) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Liver.

Cross-references

Sequence databases
EMBLGenBankDDBJ	CR860960 mRNA. Translation: CAH93062.1.
RefSeq	NP_001127624.1.
UniGene	Pab.18587
3D structure databases
ModBase	Search...
Genome annotation databases
GeneID	100174703.
Phylogenomic databases
HOVERGEN	Q5R5A4.
Enzyme and pathway databases
BRENDA	3.4.21.45. 269192.
Family and domain databases
InterPro	IPR002172. LDL_rcpt_classA_cys-rich. IPR018114. Peptidase_S1/S6_AS. IPR001254. Peptidase_S1_S6. IPR001314. Peptidase_S1A. IPR002350. Prot_inh_Kazal. IPR011497. Prot_Inh_Kazal_2. IPR001190. Srcr_rcpt. IPR017448. Srcr_rcpt-rel. [Graphical view]
Gene3D	G3DSA:4.10.400.10. LDL_rcpt_classA_cys-rich. 1 hit.
Pfam	PF07648. Kazal_2. 1 hit. PF00057. Ldl_recept_a. 2 hits. PF00530. SRCR. 1 hit. PF00089. Trypsin. 1 hit. [Graphical view]
PRINTS	PR00722. CHYMOTRYPSIN. PR00261. LDLRECEPTOR.
SMART	SM00280. KAZAL. 1 hit. SM00192. LDLa. 2 hits. SM00202. SR. 1 hit. SM00020. Tryp_SPc. 1 hit. [Graphical view]
PROSITE	PS01209. LDLRA_1. 1 hit. PS50068. LDLRA_2. 2 hits. PS00420. SRCR_1. False negative. PS50287. SRCR_2. 1 hit. PS50240. TRYPSIN_DOM. 1 hit. PS00134. TRYPSIN_HIS. 1 hit. PS00135. TRYPSIN_SER. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

CFAI_PONAB

Accession

Primary (citable) accession number: Q5R5A4

Entry history

Integrated into UniProtKB/Swiss-Prot:	May 1, 2007
Last sequence update:	December 21, 2004
Last modified:	June 16, 2009
This is version 30 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)