ATXN1 Gene (Ataxin 1)
Genetic and Functional Insights into ATXN1, a Key Player in Spinocerebellar Ataxia and Neurodegeneration
Gene Information Card
| Symbol | ATXN1 |
|---|---|
| Full Name | Ataxin 1 |
| Gene Type | Protein coding |
| Chromosomal Location | 6p22.3 |
| NCBI Gene ID | 6310 ncbi.nlm.nih.gov/gene/6310 |
| Ensembl ID | ENSG00000124788 |
| UniProt ID | P54253 |
| OMIM ID | 601556 |
| HGNC ID | 799 |
| Aliases | SCA1, ATX1, D6S504E |
Description
The ATXN1 gene (ataxin 1) is located on chromosome 6p22.3 and encodes a protein of 816 amino acids. It is widely expressed in the brain and other tissues. The protein contains a polyglutamine tract near its N-terminus; expansion of this tract beyond ~39 repeats causes spinocerebellar ataxia type 1 (SCA1), a progressive neurodegenerative disorder. ATXN1 functions in transcriptional regulation, RNA processing, and chromatin remodeling through interactions with factors such as Capicua (CIC) and RBM17.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Spinocerebellar ataxia type 1 (SCA1) | Expanded CAG repeat (≥39) in ATXN1 leads to polyglutamine expansion, causing protein misfolding, aggregation, and neuronal dysfunction in cerebellar Purkinje cells and brainstem nuclei. | OMIM #164400; ClinVar; multiple peer-reviewed studies |
| Spinocerebellar ataxia type 1 with cognitive impairment | Same CAG expansion mechanism; additional cortical involvement leads to executive dysfunction and memory deficits. | ClinVar; literature review |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Cerebellum | 12.5 | Medium |
| Cerebral cortex | 8.2 | Medium |
| Heart | 6.1 | Low |
| Testis | 5.8 | Low |
| Liver | 4.3 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| SH-SY5Y (neuroblastoma) | 10.1 | Neuronal model; high expression |
| HeLa (cervical carcinoma) | 7.3 | Moderate expression |
| HEK293 (embryonic kidney) | 6.5 | Moderate expression |
| U-87 MG (glioblastoma) | 9.8 | High expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| CAG repeat expansion (≥39) | Trinucleotide repeat expansion | ~1 in 100,000 (SCA1 prevalence) | Gain of toxic function; protein aggregation and neurodegeneration |
| c.1930G>A (p.Gly644Arg) | Missense | Rare | Unknown; reported in ClinVar as likely benign |
| c.2750A>G (p.Asn917Ser) | Missense | Rare | Uncertain significance; ClinVar |
Mutation functional classification
Loss of Function (LOF)
Not established as a primary mechanism for SCA1; expanded ATXN1 retains some normal functions but acquires toxic properties.
Gain of Function (GOF)
Expanded polyglutamine tract confers a toxic gain of function, leading to protein aggregation, altered protein-protein interactions, and neuronal death.
Dominant Negative (DN)
Expanded ATXN1 may interfere with normal ataxin 1 function (e.g., CIC repression), contributing to pathogenesis.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Spinocerebellar ataxia (KEGG hsa05017)
• Transcriptional misregulation in cancer (KEGG hsa05202)
• RNA splicing (Reactome R-HSA-72163)
Protein Summary
Ataxin 1 is a nuclear protein of 816 amino acids (UniProt P54253) with a polyglutamine tract (normally 6-35 repeats) near the N-terminus. It contains an AXH domain (residues 570-689) that mediates protein-protein interactions, including with Capicua (CIC) and RBM17. Ataxin 1 functions as a transcriptional repressor and is involved in RNA processing and chromatin remodeling. Pathogenic expansion of the polyglutamine tract (≥39 repeats) leads to misfolding, aggregation, and selective neurodegeneration characteristic of spinocerebellar ataxia type 1.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| ATXN10 Knockout HEK293 Cell Line | EDJ-KQ8242 | Human | 25814 | Details Get a Quote |
| ATXN1L Knockout HEK293 Cell Line | EDJ-KQ12490 | Human | 342371 | Details Get a Quote |
| ATXN10 Knockout A-549 Cell Line | EDJ-KQ34163 | Human | 25814 | Details Get a Quote |
| ATXN10 Knockout HCT 116 Cell Line | EDJ-KQ34164 | Human | 25814 | Details Get a Quote |
| ATXN10 Knockout HeLa Cell Line | EDJ-KQ34165 | Human | 25814 | Details Get a Quote |
| ATXN1L Knockout A-549 Cell Line | EDJ-KQ41456 | Human | 342371 | Details Get a Quote |
| ATXN1L Knockout HCT 116 Cell Line | EDJ-KQ41457 | Human | 342371 | Details Get a Quote |
| ATXN1L Knockout HeLa Cell Line | EDJ-KQ41458 | Human | 342371 | Details Get a Quote |
| ATXN1 Knockout HEK293 Cell Line | EDJ-KQ50609 | Human | 6310 | Details Get a Quote |
| ATXN1 Knockout HeLa Cell Line | EDJ-KQ54393 | Human | 6310 | Details Get a Quote |
| ATXN1 Knockout A-549 Cell Line | EDJ-KQ62885 | Human | 6310 | Details Get a Quote |
| ATXN1 Knockout HCT 116 Cell Line | EDJ-KQ71351 | Human | 6310 | Details Get a Quote |
