CR1

CR1 (Complement C3b/C4b Receptor 1 (Knops Blood Group)) is a Protein Coding gene. Diseases associated with CR1 include Malaria and Plasmodium Falciparum Malaria. Among its related pathways are Creation of C4 and C2 activators and Primary Focal Segmental Glomerulosclerosis FSGS. Gene Ontology (GO) annotations related to this gene include complement component C3b binding and complement component C4b receptor activity. An important paralog of this gene is CSMD1.

Full Name

Complement C3b/C4b Receptor 1 (Knops Blood Group)

Function

Membrane immune adherence receptor that plays a critical role in the capture and clearance of complement-opsonized pathogens by erythrocytes and monocytes/macrophages (PubMed:2963069).

Mediates the binding by these cells of particles and immune complexes that have activated complement to eliminate them from the circulation (PubMed:2963069).

Acts also in the inhibition of spontaneous complement activation by impairing the formation and function of the alternative and classical pathway C3/C5 convertases, and by serving as a cofactor for the cleavage by factor I of C3b to iC3b, C3c and C3d,g, and of C4b to C4c and C4d (PubMed:2972794, PubMed:8175757).

Plays also a role in immune regulation by contributing, upon ligand binding, to the generation of regulatory T cells from activated helper T cells (PubMed:25742728).

(Microbial infection) Acts as a receptor for Epstein-Barr virus.

Biological Process

ATP export Source: ARUK-UCL
Complement activation, alternative pathway Source: ARUK-UCL
Complement activation, classical pathway Source: UniProtKB-KW
Complement receptor mediated signaling pathway Source: ARUK-UCL
Immune complex clearance by erythrocytes Source: ARUK-UCL
Negative regulation of activation of membrane attack complex Source: ARUK-UCL
Negative regulation of complement activation Source: ARUK-UCL
Negative regulation of complement activation, alternative pathway Source: UniProtKB
Negative regulation of complement activation, classical pathway Source: UniProtKB
Negative regulation of cytolysis Source: ARUK-UCL
Negative regulation of immunoglobulin production Source: ARUK-UCL
Negative regulation of interferon-gamma production Source: ARUK-UCL
Negative regulation of interleukin-2 production Source: ARUK-UCL
Negative regulation of plasma cell differentiation Source: ARUK-UCL
Negative regulation of serine-type endopeptidase activity Source: UniProtKB
Negative regulation of T cell proliferation Source: ARUK-UCL
Neutrophil degranulation Source: Reactome
Plasma membrane organization Source: ARUK-UCL
Positive regulation of activation of membrane attack complex Source: ARUK-UCL
Positive regulation of cell population proliferation Source: ARUK-UCL
Positive regulation of regulatory T cell differentiation Source: ARUK-UCL
Positive regulation of serine-type endopeptidase activity Source: UniProtKB
Regulation of complement activation Source: Reactome
Regulation of regulatory T cell differentiation Source: Reactome

Cellular Location

Membrane

Topology

Extracellular: 42-1971
Helical: 1972-1996
Cytoplasmic: 1997-2039

CR1

Anti-CR1 antibodies