STAG3 Gene - Stromal Antigen 3
Cohesin complex component involved in sister chromatid cohesion and meiosis
Gene Information Card
| Symbol | STAG3 |
|---|---|
| Full Name | Stromal Antigen 3 |
| Gene Type | Protein coding |
| Chromosomal Location | 7q22.1 |
| NCBI Gene ID | 10734 ncbi.nlm.nih.gov/gene/10734 |
| Ensembl ID | ENSG00000166923 |
| UniProt ID | Q9UJ98 |
| OMIM ID | 608489 |
| HGNC ID | 11356 |
| Aliases | SA3, stromal antigen 3, SCC3 homolog |
Description
STAG3 encodes a component of the cohesin complex, which is essential for sister chromatid cohesion during mitosis and meiosis. The protein specifically localizes to meiotic chromosomes and is required for proper chromosome segregation, synapsis, and recombination. Mutations in STAG3 are associated with premature ovarian failure and have been implicated in various cancers.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Premature ovarian failure 8 (POF8) | Loss-of-function mutations disrupt cohesin complex function, leading to meiotic arrest and ovarian failure | OMIM #615723 |
| Ovarian cancer | Somatic mutations and altered expression contribute to genomic instability | COSMIC |
| Breast cancer | STAG3 overexpression or mutation may promote aneuploidy | COSMIC |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 12.3 | Medium |
| Ovary | 8.7 | Medium |
| Lymph node | 5.1 | Low |
| Bone marrow | 4.2 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| K562 | 6.5 | Leukemia cell line |
| HeLa | 4.8 | Cervical cancer cell line |
| A549 | 3.9 | Lung cancer cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1081C>T (p.Arg361*) | Nonsense | Rare | Loss of function; associated with POF8 |
| c.1546_1547del (p.Leu516fs) | Frameshift | Rare | Loss of function; associated with POF8 |
| c.2035G>A (p.Glu679Lys) | Missense | Somatic | Unknown effect; reported in ovarian cancer |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations in STAG3 lead to truncated or absent protein, disrupting cohesin complex function and causing meiotic defects.
Gain of Function (GOF)
No gain-of-function mutations have been reported for STAG3.
Dominant Negative (DN)
No dominant-negative mutations have been characterized for STAG3.
View complete mutation data：
Gene Ontology (GO)
| • sister chromatid cohesion (GO:0007062) | • condensed nuclear chromosome (GO:0000794) |
| • nucleus (GO:0005634) | • zinc ion binding (GO:0008270) |
| • homologous chromosome pairing (GO:0007129) |
Pathways
• Cohesin complex (Reactome: R-HSA-2467813)
• Meiotic recombination (Reactome: R-HSA-912446)
• Cell cycle
• mitotic (Reactome: R-HSA-69278)
Protein Summary
STAG3 is a 135 kDa protein that forms part of the cohesin complex, interacting with SMC1, SMC3, and RAD21. It is specifically expressed in germ cells and is critical for meiotic chromosome dynamics. The protein contains a stromal antigen domain and is involved in maintaining genome stability.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| STAG3 Knockout HEK293 Cell Line | EDJ-KQ7148 | Human | 10734 | Details Get a Quote |
| STAG3 Knockout A-549 Cell Line | EDJ-KQ32049 | Human | 10734 | Details Get a Quote |
| STAG3 Knockout HeLa Cell Line | EDJ-KQ32051 | Human | 10734 | Details Get a Quote |
| STAG3 Knockout HCT 116 Cell Line | EDJ-KQ30669 | Human | 10734 | Details Get a Quote |
