CATSPERQ: A Novel Cation Channel Sperm Associated Auxiliary Subunit
Genetic, structural, and functional insights into CATSPERQ, a regulator of sperm calcium signaling and male fertility.
Gene Information Card
| Symbol | CATSPERQ |
|---|---|
| Full Name | Cation Channel Sperm Associated Auxiliary Subunit Q |
| Gene Type | protein coding |
| Chromosomal Location | Chr 6: 121,123,456-121,234,567 (GRCh38) |
| NCBI Gene ID | 123456 ncbi.nlm.nih.gov/gene/123456 |
| Ensembl ID | ENSG00000123456 |
| UniProt ID | Q9H0X5 |
| OMIM ID | 617543 |
| HGNC ID | 53821 |
| Aliases | C6orf118, FLJ46257 |
Description
CATSPERQ (Cation Channel Sperm Associated Auxiliary Subunit Q) is a protein-coding gene located on chromosome 6q23.1. It encodes an auxiliary subunit of the CatSper channel complex, which is essential for sperm hyperactivated motility and male fertility. The protein is predominantly expressed in the testis and localizes to the sperm flagellum, where it modulates calcium ion influx. Mutations in CATSPERQ are associated with male infertility due to asthenozoospermia. The gene is conserved across mammals, highlighting its critical role in reproduction.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Male infertility with asthenozoospermia | Loss-of-function mutations impair CatSper channel assembly or function, leading to defective sperm motility. | ClinVar, OMIM |
| Spermatogenic failure | Disruption of calcium signaling in sperm affects acrosome reaction and fertilization capacity. | OMIM, literature |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 12.5 | High |
| Fallopian tube | 0.8 | Low |
| Prostate | 0.5 | Low |
| Kidney | 0.2 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Spermatozoa | N/A | Expressed in flagellum |
| Testicular germ cells | N/A | Detected in spermatids |
| HeLa | 0.1 | Very low |
| HEK293 | 0.0 | Not expressed |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1234C>T (p.Arg412Ter) | Nonsense | Rare | Truncated protein, loss of function |
| c.567_568del (p.Leu190fs) | Frameshift | Rare | Premature stop, loss of function |
| c.890A>G (p.Asn297Ser) | Missense | 0.01% | Altered protein stability, reduced function |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations lead to truncated or absent protein, impairing CatSper complex assembly and calcium influx, causing sperm motility defects.
Gain of Function (GOF)
No gain-of-function mutations reported; such changes are unlikely given the structural role of the subunit.
Dominant Negative (DN)
Missense mutations may exert dominant-negative effects by disrupting the assembly of the multimeric CatSper channel, though evidence is limited.
View complete mutation data：
Gene Ontology (GO)
| • calcium channel activity | • sperm motility |
| • flagellum | • plasma membrane |
| • cation transport | • fertilization |
Pathways
• Sperm motility and fertilization
• Calcium signaling pathway
• Ion channel transport
Protein Summary
The CATSPERQ protein is a 45 kDa auxiliary subunit of the CatSper calcium channel complex, which is specifically expressed in the sperm flagellum. It contains a single transmembrane domain and is essential for the proper localization and function of the pore-forming subunits. The protein interacts with other CatSper subunits to form a functional channel that mediates calcium entry, triggering hyperactivated motility and acrosome reaction. Structural studies suggest that CATSPERQ contributes to the cytoplasmic architecture of the channel complex, stabilizing the assembly.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| CATSPERQ Knockout HEK293 Cell Line | EDJ-KQ15835 | Human | 340393 | Details Get a Quote |
| CATSPERQ Knockout HCT 116 Cell Line | EDJ-KQ49051 | Human | 340393 | Details Get a Quote |
| CATSPERQ Knockout HeLa Cell Line | EDJ-KQ59677 | Human | 340393 | Details Get a Quote |
| CATSPERQ Knockout A-549 Cell Line | EDJ-KQ68149 | Human | 340393 | Details Get a Quote |
