BLK Gene - B Lymphoid Kinase
Comprehensive gene information for BLK (B Lymphoid Kinase) including genomic context, expression, mutations, and associated diseases.
Gene Information Card
| Symbol | BLK |
|---|---|
| Full Name | BLK proto-oncogene, Src family tyrosine kinase |
| Gene Type | protein-coding |
| Chromosomal Location | 8p23.1 |
| NCBI Gene ID | 640 ncbi.nlm.nih.gov/gene/640 |
| Ensembl ID | ENSG00000136573 |
| UniProt ID | P51451 |
| OMIM ID | 191305 |
| HGNC ID | 1057 |
| Aliases | MGC10471, MODY11 |
Description
BLK (B lymphoid kinase) is a member of the Src family of non-receptor tyrosine kinases. It is primarily expressed in B cells and plays a critical role in B-cell receptor signaling, B-cell development, and differentiation. Mutations and altered expression of BLK have been implicated in autoimmune diseases such as systemic lupus erythematosus (SLE) and in certain cancers, including B-cell malignancies.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Systemic Lupus Erythematosus | BLK variants reduce kinase activity, impairing B-cell receptor signaling and leading to autoimmunity. | OMIM, ClinVar |
| Maturity-Onset Diabetes of the Young Type 11 (MODY11) | Loss-of-function mutations in BLK impair insulin secretion from pancreatic beta cells. | OMIM |
| B-cell Non-Hodgkin Lymphoma | BLK overexpression or activating mutations may promote B-cell proliferation. | COSMIC |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Lymph node | 12.5 | Medium |
| Spleen | 10.2 | Medium |
| Bone marrow | 8.9 | Medium |
| Whole blood | 6.1 | Low |
| Pancreas | 1.3 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Raji (Burkitt lymphoma) | 15.3 | B-cell line, high expression |
| Daudi (Burkitt lymphoma) | 14.1 | B-cell line, high expression |
| K562 (chronic myeloid leukemia) | 0.8 | Non-B cell, low expression |
| HEK293 (embryonic kidney) | 0.2 | Non-hematopoietic, very low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.421C>T (p.Arg141Cys) | Missense | Rare | Reduced kinase activity; associated with SLE |
| c.988G>A (p.Gly330Arg) | Missense | Rare | Impaired B-cell receptor signaling; MODY11 |
| c.1147G>A (p.Glu383Lys) | Missense | Somatic (COSMIC) | Potential gain-of-function in lymphoma |
Mutation functional classification
Loss of Function (LOF)
Missense mutations (e.g., p.Arg141Cys, p.Gly330Arg) reduce or abolish kinase activity, impairing B-cell receptor signaling and contributing to SLE and MODY11.
Gain of Function (GOF)
Somatic mutations (e.g., p.Glu383Lys) may enhance kinase activity, promoting B-cell proliferation in lymphoma.
Dominant Negative (DN)
Not well documented for BLK; most reported mutations are loss-of-function or gain-of-function.
View complete mutation data：
Gene Ontology (GO)
Pathways
• B cell receptor signaling pathway (Reactome: R-HSA-983705)
• Fc epsilon receptor (FCERI) signaling (Reactome: R-HSA-2454202)
• Signaling by Src-family kinases (Reactome: R-HSA-912526)
Protein Summary
BLK encodes a 55 kDa protein (UniProt P51451) belonging to the Src family of tyrosine kinases. It contains SH3, SH2, and tyrosine kinase domains. BLK is activated upon B-cell receptor engagement and phosphorylates downstream targets such as CD19 and BLNK, regulating B-cell activation, proliferation, and survival. In pancreatic beta cells, BLK modulates insulin secretion. Dysregulation of BLK contributes to autoimmune and metabolic diseases.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| BLK Knockout HEK293 Cell Line | EDJ-KQ1929 | Human | 640 | Details Get a Quote |
| BLK Knockout HeLa Cell Line | EDJ-KQ52721 | Human | 640 | Details Get a Quote |
| BLK Knockout A-549 Cell Line | EDJ-KQ61192 | Human | 640 | Details Get a Quote |
| BLK Knockout HCT 116 Cell Line | EDJ-KQ69684 | Human | 640 | Details Get a Quote |
