Protein: CO4B
Complement C4-B (Basic complement C4) (C3 and PZP-like alpha-2-macroglobulin domain-containing protein 3) [Cleaved into: Complement C4 beta chain; Complement C4-B alpha chain; C4a anaphylatoxin; Complement C4b-B; C4d-B; Complement C4 gamma chain]

Gene: CO4B, C4B
Organism: Homo sapiens
Interactions: 21
UniProt ID: P0C0L5

Gene Ontology (top 5):
GO:0001848 - complement binding
GO:0004866 - endopeptidase inhibitor activity
GO:0005576 - extracellular region
GO:0005615 - extracellular space
GO:0005886 - plasma membrane

Download interactions: TXT   MITAB-2.5

Interaction Interactor Experiments Homologs Category Interaction
Score
Confidence

125804

MASP2
Mannan-binding lectin serine protease 2

3

8

Small-scale

0.827

High

444676

CO2
Complement C2

1

20

Small-scale

0.618

High

501865

MCP
Membrane cofactor protein

1

20

Small-scale

0.618

High

501867

MASP1
Mannan-binding lectin serine protease 1

1

7

Small-scale

0.618

High

501874

FHR4
Complement factor H-related protein 4

1

20

Small-scale

0.618

High

210693

KLK10
Kallikrein-10

1

8

High-throughput

0.575

High

425237

CFAI
Complement factor I

1

1

Small-scale

0.575

High

486868

C1S
Complement C1s subcomponent

1

7

Small-scale

0.575

High

501866

CCR1
C-C chemokine receptor type 1

1

5

High-throughput

0.575

High

501864

TAU
Microtubule-associated protein tau

1

3

High-throughput

0.445

High

501878

GBG8
Guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-8

1

2

High-throughput

0.445

High

277259

PITX3
Pituitary homeobox 3

1

3

Small-scale

0.437

High

501872

FBX22
F-box only protein 22

1

1

High-throughput

0.437

High

501868

2ABB
Serine/threonine-protein phosphatase 2A 55 kDa regulatory subunit B beta isoform

1

4

High-throughput

0.407

High

501869

KIF22
Kinesin-like protein KIF22

1

1

High-throughput

0.407

High

501870

CR021
UPF0711 protein C18orf21

1

3

High-throughput

0.407

High

501871

UBE2U
Ubiquitin-conjugating enzyme E2 U

1

3

High-throughput

0.407

High

501873

RHBL4
Rhomboid-related protein 4

1

4

High-throughput

0.407

High

501875

PLCA
1-acyl-sn-glycerol-3-phosphate acyltransferase alpha

1

5

High-throughput

0.407

High

501876

MBNL1
Muscleblind-like protein 1

1

3

High-throughput

0.407

High

501877

PHF11
PHD finger protein 11

1

5

High-throughput

0.407

High


Service provided by Combinatics, Japan

Last updated: 11Aug2025