SSR3: Signal Sequence Receptor Subunit 3
A component of the translocon complex involved in protein translocation across the endoplasmic reticulum membrane.
Gene Information Card
| Symbol | SSR3 |
|---|---|
| Full Name | Signal Sequence Receptor Subunit 3 |
| Gene Type | Protein coding |
| Chromosomal Location | 3q25.31 |
| NCBI Gene ID | 6747 ncbi.nlm.nih.gov/gene/6747 |
| Ensembl ID | ENSG00000114770 |
| UniProt ID | Q9Y6A1 |
| OMIM ID | 606213 |
| HGNC ID | 11327 |
| Aliases | TRAPγ, SSRγ, signal sequence receptor gamma |
Description
The SSR3 gene encodes the gamma subunit of the signal sequence receptor (SSR) complex, also known as the translocon-associated protein (TRAP) complex. This complex is part of the protein translocation machinery in the endoplasmic reticulum (ER) membrane, facilitating the recognition and translocation of nascent polypeptides with signal sequences. SSR3 is essential for efficient protein transport and quality control in the secretory pathway.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Cancer (various types) | Altered SSR3 expression may affect protein trafficking and ER stress response, contributing to tumorigenesis. | PubMed (PMID: 25944712) |
| Neurodegenerative disorders | Dysregulation of SSR3 can impair ER protein homeostasis, potentially linked to neurodegeneration. | PubMed (PMID: 28431233) |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Adipose tissue | 12.5 | Medium |
| Brain | 8.3 | Low |
| Liver | 15.2 | Medium |
| Pancreas | 10.1 | Medium |
| Testis | 18.7 | High |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | 14.2 | Cervical cancer cell line |
| HEK293 | 11.5 | Embryonic kidney cell line |
| K562 | 9.8 | Leukemia cell line |
| MCF7 | 13.0 | Breast cancer cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.374C>T (p.Thr125Met) | Missense | <0.01% | Unknown functional impact |
| c.521A>G (p.Asn174Ser) | Missense | <0.01% | Unknown functional impact |
Mutation functional classification
Loss of Function (LOF)
No confirmed loss-of-function mutations reported in SSR3.
Gain of Function (GOF)
No confirmed gain-of-function mutations reported in SSR3.
Dominant Negative (DN)
No confirmed dominant-negative mutations reported in SSR3.
View complete mutation data：
Gene Ontology (GO)
| • signal sequence binding (GO:0005047) | • endoplasmic reticulum (GO:0005783) |
| • endoplasmic reticulum membrane (GO:0005789) | • SRP-dependent cotranslational protein targeting to membrane (GO:0006614) |
| • integral component of membrane (GO:0016021) |
Pathways
• Protein processing in endoplasmic reticulum (KEGG: hsa04141)
• Cotranslational protein targeting to membrane (Reactome: R-HSA-1799339)
Protein Summary
SSR3 encodes the gamma subunit of the signal sequence receptor (SSR) complex, a transmembrane protein of 180 amino acids (20 kDa). It localizes to the endoplasmic reticulum membrane and interacts with other SSR subunits (α, β, δ) to form the TRAP complex. The protein is involved in the recognition of signal peptides and the translocation of nascent proteins into the ER lumen. SSR3 is widely expressed, with highest levels in testis and adipose tissue.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SSR3 Knockout HEK293 Cell Line | EDJ-KQ5847 | Human | 6747 | Details Get a Quote |
| SSR3 Knockout A-549 Cell Line | EDJ-KQ29309 | Human | 6747 | Details Get a Quote |
| SSR3 Knockout HCT 116 Cell Line | EDJ-KQ29310 | Human | 6747 | Details Get a Quote |
| SSR3 Knockout HeLa Cell Line | EDJ-KQ29311 | Human | 6747 | Details Get a Quote |
Displaying Records 1 To 4 Of 4 Records
