Printable factfile
Gene Information
Names
HUGO name: C8A
Alias(es):
- complement component 8, alpha polypeptide
- Complement component C8 alpha chain precursor
Localization
Reference sequences
- DNA: AL121998 (EMBL)
- cDNA: M16974 (EMBL)
- Protein: P07357 (SWISSPROT)
- Other Sequences
Chromosomal location
Maps
Variations / Mutations
Other gene-based resources
Protein Information
Description
Protein function:
C8 is a constituent of the membrane attack complex (MAC). C8 binds to the C5b-7 complex, forming the C5b-8 complex. C5-b8 binds C9 and acts as a catalyst in the polymerization of C9.
Subunit:
C8 is composed of three chains: alpha, beta and gamma. The alpha and gamma chains are disulfide bonded.
Subcellular location:
Secreted.
Structures (PDB)
Domains
Tsp type-1 1 domain: 38-93
Ldl-receptor class a domain: 94-132
Egf-like domain: 493-529
Tsp type-1 2 domain: 536-584
Other features
Signal peptide: 1-20
Propeptide: 21-30
Complement component c8 alpha chain: 31-584
Disulfide bond: 96-108
Disulfide bond: 102-121
Disulfide bond: 115-130
Disulfide bond interchain (with c8-gamma): 194
Disulfide bond: 375-399
Other related resourses:
- PIR: C8HUA
- InterPro: IPR002172; LDL_recept_A
- InterPro: IPR001862; MAC_perforin
- InterPro: IPR000884; TSP1
- Pfam: PF00057; ldl_recept_a
- Pfam: PF00090; tsp_1
- Pfam: PF01823; MACPF
- SMART: SM00192; LDLa
- SMART: SM00457; MACPF
- SMART: SM00209; TSP1
- PROSITE: PS00022; EGF_1
- PROSITE: PS01186; EGF_2
- PROSITE: PS01209; LDLRA_1
- PROSITE: PS50068; LDLRA_2
- PROSITE: PS00279; MAC_PERFORIN
- PROSITE: PS50092; TSP1
Expression
Expression pattern for human
| Tissue | Expression (%) | Clones |
|---|---|---|
| gall bladder | 52.46 | 3:2435 |
| hepatocellular carcinoma | 17.96 | 6:14226 |
| liver | 11.45 | 7:26031 |
| corresponding non cancerous liver tissue | 9.18 | 3:13909 |
| spleen | 5.89 | 1:7229 |
| pool, liver+spleen | 2.78 | 4:61327 |
| lung | 0.27 | 1:155782 |