CD19 molecule
Sign in to saveAlso known as differentiation antigen CD19, B-lymphocyte surface antigen B4, T-cell surface antigen Leu-12, B-lymphocyte antigen CD19, CD19, Antigens, C19, Antigens, CD19
B-lymphocyte antigen CD19, also known as CD19 molecule (Cluster of Differentiation 19), B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12 and CVID3 is a transmembrane protein that in humans is encoded by the gene CD19. In humans, CD19 is expressed in all B lineage cells. Contrary to some early doubts, human plasma cells do express CD19. CD19 plays two major roles in human B cells: on the one hand, it acts as an adaptor protein to recruit cytoplasmic signaling proteins to the membrane; on the other, it works within the CD19/CD21 complex to decrease the threshold for B cell receptor
Protein · UniProt
B-lymphocyte antigen CD19
- Gene
- CD19
- Organism
- Homo sapiens (Human)
- Length
- 556 aa
- Molecular mass
- 61,128 Da
- Evidence
- 1: Evidence at protein level
Functions as a coreceptor for the B-cell antigen receptor complex (BCR) on B-lymphocytes (PubMed:29523808). Decreases the threshold for activation of downstream signaling pathways and for triggering B-cell responses to antigens (PubMed:1373518, PubMed:16672701, PubMed:2463100). Activates signaling pathways that lead to the activation of phosphatidylinositol 3-kinase and the mobilization of intracellular Ca(2+) stores (PubMed:12387743, PubMed:16672701, PubMed:9317126, PubMed:9382888). Is not required for early steps during B cell differentiation in the blood marrow (PubMed:9317126). Required…
Swiss-Prot (reviewed) · via UniProt
~10 min read
Article
14 sectionsContents
- Structure
- Expression
- Function
- Role in development & survival
- BCR-independent
- CD19/CD21 complex
- BCR-dependent
- Interactions
- In disease
- Autoimmunity & immunodeficiency
- Cancer
- References
- Further reading
- External links
B-lymphocyte antigen CD19, also known as CD19 molecule (Cluster of Differentiation 19), B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12 and CVID3 is a transmembrane protein that in humans is encoded by the gene CD19. In humans, CD19 is expressed in all B lineage cells. Contrary to some early doubts, human plasma cells do express CD19. CD19 plays two major roles in human B cells: on the one hand, it acts as an adaptor protein to recruit cytoplasmic signaling proteins to the membrane; on the other, it works within the CD19/CD21 complex to decrease the threshold for B cell receptor signaling pathways. Due to its presence on all B cells, it is a biomarker for B lymphocyte development, lymphoma diagnosis and can be utilized as a target for leukemia immunotherapies.
== Structure == In humans, CD19 is encoded by the 7.41 kilobase CD19 gene located on the short arm of chromosome 16. It contains at least fifteen exons, four that encode extracellular domain and nine that encode cytoplasmic domains, with a total of 556 amino acids. Experiments show that there are multiple mRNA transcripts; however, only two have been isolated in vivo.