OCSTAMP Gene
Osteoclast Stimulatory Transmembrane Protein
Gene Information Card
| Symbol | OCSTAMP |
|---|---|
| Full Name | Osteoclast Stimulatory Transmembrane Protein |
| Gene Type | Protein coding |
| Chromosomal Location | 20q13.12 |
| NCBI Gene ID | 128506 ncbi.nlm.nih.gov/gene/128506 |
| Ensembl ID | ENSG00000101204 |
| UniProt ID | Q5T7M4 |
| OMIM ID | 617888 |
| HGNC ID | 26796 |
| Aliases | C20orf123, dJ1181N3.1, FLJ22662 |
Description
OCSTAMP (Osteoclast Stimulatory Transmembrane Protein) encodes a multi-pass transmembrane protein that plays a critical role in osteoclast fusion and bone resorption. It is predominantly expressed in osteoclasts and is essential for the formation of multinucleated osteoclasts. The protein localizes to the plasma membrane and is involved in cell-cell fusion during osteoclastogenesis. Mutations in OCSTAMP have been associated with osteopetrosis and other bone remodeling disorders.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Osteopetrosis | Loss-of-function mutations impair osteoclast fusion, leading to defective bone resorption and increased bone density. | ClinVar, OMIM |
| Osteoporosis | Altered OCSTAMP expression may contribute to excessive bone resorption by enhancing osteoclast activity. | NCBI Gene, PubMed |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Bone marrow | 12.5 | Medium |
| Spleen | 8.3 | Low |
| Lung | 6.1 | Low |
| Blood | 4.7 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Osteoclasts (primary) | 15.2 | High expression; key for fusion |
| THP-1 (monocyte) | 2.1 | Low baseline; upregulated upon differentiation |
| RAW 264.7 (macrophage) | 1.8 | Induced during osteoclastogenesis |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.325C>T (p.Arg109*) | Nonsense | Rare | Loss of function; associated with osteopetrosis |
| c.487G>A (p.Gly163Ser) | Missense | 0.01% | Unknown significance; predicted damaging |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations that truncate the protein impair osteoclast fusion, leading to osteopetrosis.
Gain of Function (GOF)
Not reported in OCSTAMP.
Dominant Negative (DN)
Not reported in OCSTAMP.
View complete mutation data：
Gene Ontology (GO)
| • osteoclast fusion (GO:0035987) | • bone resorption (GO:0045453) |
| • integral component of membrane (GO:0016021) | • plasma membrane (GO:0005886) |
Pathways
• Osteoclast differentiation (RANKL signaling)
• Cell-cell fusion pathway
Protein Summary
OCSTAMP is a 4-transmembrane domain protein of 223 amino acids. It is expressed on the plasma membrane of osteoclast precursors and mature osteoclasts. The protein facilitates cell-cell fusion by interacting with other fusion machinery components, such as DC-STAMP. It is essential for the formation of multinucleated osteoclasts capable of efficient bone resorption. Structural studies suggest that its extracellular loops mediate homophilic interactions during fusion.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| OCSTAMP Knockout HEK293 Cell Line | EDJ-KQ9175 | Human | 128506 | Details Get a Quote |
| OCSTAMP Knockout HeLa Cell Line | EDJ-KQ58242 | Human | 128506 | Details Get a Quote |
| OCSTAMP Knockout A-549 Cell Line | EDJ-KQ66729 | Human | 128506 | Details Get a Quote |
| OCSTAMP Knockout HCT 116 Cell Line | EDJ-KQ75140 | Human | 128506 | Details Get a Quote |
