MS4A1

Function

B-lymphocyte-specific membrane protein that plays a role in the regulation of cellular calcium influx necessary for the development, differentiation, and activation of B-lymphocytes (PubMed:3925015, PubMed:7684739, PubMed:12920111). Functions as a store-operated calcium (SOC) channel component promoting calcium influx after activation by the B-cell receptor/BCR (PubMed:7684739, PubMed:12920111, PubMed:18474602).

Involvement in disease

Immunodeficiency, common variable, 5

CVID5

A primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen. The defect results from a failure of B-cell differentiation and impaired secretion of immunoglobulins; the numbers of circulating B-cells is usually in the normal range, but can be low.

None

The disease is caused by variants affecting the gene represented in this entry.

Post-translational modifications

Phosphorylated on serines and threonines in resting B-cells. Protein kinase C/PKC can use CD20 as substrate.

Sequence similarities

Belongs to the MS4A family.

Tissue specificity

Expressed on B-cells.

Cellular localization

• Cell membrane
• Multi-pass membrane protein
• Cell membrane
• Lipid-anchor
• Constitutively associated with membrane rafts.

Alternative names

• B-lymphocyte antigen CD20
• B-lymphocyte surface antigen B1
• Bp35
• Leukocyte surface antigen Leu-16
• Membrane-spanning 4-domains subfamily A member 1
• MS4A1
• CD20

Database links

• entrezGene:931
• omim:112210
• swissprot:P11836

Target type

Proteins

Primary research area

Immunology & Infectious Disease

Other research areas

• Immuno-oncology
• Neuroscience

Molecular weight

33077Da