SIRPB1: Signal Regulatory Protein Beta 1
A transmembrane immune receptor involved in phagocytosis and cell signaling
Gene Information Card
| Symbol | SIRPB1 |
|---|---|
| Full Name | Signal Regulatory Protein Beta 1 |
| Gene Type | protein-coding |
| Chromosomal Location | 20p13 |
| NCBI Gene ID | 10326 ncbi.nlm.nih.gov/gene/10326 |
| Ensembl ID | ENSG00000101445 |
| UniProt ID | O00241 |
| OMIM ID | 603889 |
| HGNC ID | 10847 |
| Aliases | CD172b, SIRP-B1, SIRPbeta1 |
Description
SIRPB1 (Signal Regulatory Protein Beta 1) encodes a transmembrane receptor belonging to the signal regulatory protein (SIRP) family. It is primarily expressed on myeloid cells and functions as an activating receptor that promotes phagocytosis and immune cell signaling. SIRPB1 interacts with the ligand CD47 and associates with the adaptor protein DAP12 to initiate downstream signaling cascades. The gene is located on chromosome 20p13 and is implicated in various immune responses and cancer biology.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Acute Myeloid Leukemia | Overexpression of SIRPB1 may contribute to leukemogenesis through aberrant myeloid signaling | COSMIC, ClinVar |
| Colorectal Cancer | Altered SIRPB1 expression linked to tumor immune evasion | NCBI Gene, PubMed |
| Inflammatory Disorders | SIRPB1-mediated signaling dysregulation in macrophage activation | UniProt, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Bone Marrow | 12.5 | Medium |
| Spleen | 8.3 | Low |
| Lung | 6.1 | Low |
| Blood | 15.2 | Medium |
| Liver | 2.4 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| THP-1 (monocytic leukemia) | 18.7 | High expression |
| HL-60 (promyelocytic leukemia) | 14.2 | Moderate expression |
| K-562 (chronic myeloid leukemia) | 9.8 | Low expression |
| HEK293 (embryonic kidney) | 0.5 | Not detected |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.101C>T (p.Thr34Met) | Missense | 0.02% (gnomAD) | Unknown functional impact |
| c.205G>A (p.Gly69Arg) | Missense | 0.01% (gnomAD) | Potential loss of ligand binding |
| c.412_413insA | Frameshift | Rare | Predicted loss of function |
Mutation functional classification
Loss of Function (LOF)
Frameshift mutations (e.g., c.412_413insA) likely result in truncated protein and loss of signaling.
Gain of Function (GOF)
No confirmed gain-of-function mutations reported in SIRPB1.
Dominant Negative (DN)
Not documented for SIRPB1.
View complete mutation data：
Gene Ontology (GO)
| • phagocytosis | • signal transduction |
| • cell surface receptor signaling pathway | • innate immune response |
| • protein binding | • transmembrane signaling receptor activity |
Pathways
• CD47/SIRP signaling
• Phagocytosis
• DAP12 signaling
• Myeloid cell activation
Protein Summary
SIRPB1 is a type I transmembrane glycoprotein with three extracellular immunoglobulin-like domains and a short cytoplasmic tail lacking signaling motifs. It associates non-covalently with the immunoreceptor tyrosine-based activation motif (ITAM)-containing adaptor DAP12 to mediate activating signals in myeloid cells. The protein plays a key role in phagocytosis, cytokine production, and cell adhesion. Alternative splicing generates multiple isoforms.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SIRPB1 Knockout HEK293 Cell Line | EDJ-KQ50957 | Human | 10326 | Details Get a Quote |
| SIRPB1 Knockout HeLa Cell Line | EDJ-KQ55379 | Human | 10326 | Details Get a Quote |
| SIRPB1 Knockout A-549 Cell Line | EDJ-KQ63861 | Human | 10326 | Details Get a Quote |
| SIRPB1 Knockout HCT 116 Cell Line | EDJ-KQ72318 | Human | 10326 | Details Get a Quote |
