IBTK (Inhibitor of Bruton Tyrosine Kinase)
Gene encoding a BTK inhibitor involved in B-cell development and immune regulation
Gene Information Card
| Symbol | IBTK |
|---|---|
| Full Name | Inhibitor of Bruton Tyrosine Kinase |
| Gene Type | Protein coding |
| Chromosomal Location | 6q14.1 |
| NCBI Gene ID | 25998 ncbi.nlm.nih.gov/gene/25998 |
| Ensembl ID | ENSG00000112210 |
| UniProt ID | Q9P2D0 |
| OMIM ID | 609447 |
| HGNC ID | 17813 |
| Aliases | BTK inhibitor, FLJ20032, MGC138290, MGC138291 |
Description
IBTK (Inhibitor of Bruton Tyrosine Kinase) encodes a protein that negatively regulates Bruton tyrosine kinase (BTK) activity, thereby modulating B-cell receptor signaling and B-cell development. The gene is located on chromosome 6q14.1 and is expressed in various tissues, with highest levels in lymphoid organs. Alterations in IBTK expression or function have been implicated in immune dysregulation and cancer.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Primary immunodeficiency (agammaglobulinemia-like) | Loss of IBTK function leads to BTK hyperactivation and impaired B-cell maturation | OMIM #609447 |
| Chronic lymphocytic leukemia (CLL) | IBTK downregulation may contribute to BTK-driven proliferation | COSMIC; ClinVar |
| Diffuse large B-cell lymphoma | Altered IBTK expression linked to BTK pathway activation | COSMIC |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Spleen | 12.5 | High |
| Lymph node | 10.8 | High |
| Bone marrow | 8.3 | Medium |
| Lung | 4.2 | Low |
| Brain | 2.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Raji (Burkitt lymphoma) | 15.2 | B-cell line |
| Daudi (Burkitt lymphoma) | 14.7 | B-cell line |
| K562 (leukemia) | 6.8 | Myeloid line |
| HEK293 (embryonic kidney) | 3.5 | Non-immune line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.124C>T (p.Arg42*) | Nonsense | Rare | Loss of function |
| c.457G>A (p.Glu153Lys) | Missense | 0.01% | Unknown functional impact |
| c.789_790del (p.Leu264fs) | Frameshift | Rare | Loss of function |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations (e.g., p.Arg42*, p.Leu264fs) predicted to truncate the protein, reducing BTK inhibition.
Gain of Function (GOF)
No gain-of-function mutations reported in IBTK.
Dominant Negative (DN)
No dominant-negative mutations described.
View complete mutation data：
Gene Ontology (GO)
| • protein binding (GO:0005515) | • cytoplasm (GO:0005737) |
| • identical protein binding (GO:0042802) | • regulation of signal transduction (GO:0009966) |
| • B cell receptor signaling pathway (GO:0050853) |
Pathways
• B cell receptor signaling pathway (Reactome: R-HSA-983705)
• BTK signaling in B-cell development (KEGG: hsa04662)
Protein Summary
The IBTK protein is a 135 kDa cytoplasmic inhibitor of Bruton tyrosine kinase. It directly interacts with BTK via its N-terminal region, suppressing BTK autophosphorylation and downstream signaling. This regulation is critical for proper B-cell maturation and immune homeostasis. IBTK is expressed predominantly in hematopoietic tissues.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| IBTK Knockout HEK293 Cell Line | EDJ-KQ8345 | Human | 25998 | Details Get a Quote |
| IBTK Knockout HeLa Cell Line | EDJ-KQ33029 | Human | 25998 | Details Get a Quote |
| IBTK Knockout A-549 Cell Line | EDJ-KQ34361 | Human | 25998 | Details Get a Quote |
| IBTK Knockout HCT 116 Cell Line | EDJ-KQ34362 | Human | 25998 | Details Get a Quote |
Displaying Records 1 To 4 Of 4 Records
