SPESP1
Sperm Equatorial Segment Protein 1
Gene Information Card
| Symbol | SPESP1 |
|---|---|
| Full Name | Sperm Equatorial Segment Protein 1 |
| Gene Type | protein-coding |
| Chromosomal Location | 15q23 |
| NCBI Gene ID | 246777 ncbi.nlm.nih.gov/gene/246777 |
| Ensembl ID | ENSG00000169604 |
| UniProt ID | Q9H1Z9 |
| OMIM ID | 609336 |
| HGNC ID | 30779 |
| Aliases | SPESP1, SPESP-1 |
Description
SPESP1 (sperm equatorial segment protein 1) is a protein-coding gene located on chromosome 15q23. The encoded protein is localized to the equatorial segment of the sperm head and is essential for sperm-egg fusion during fertilization. It is expressed specifically in testis and plays a critical role in the acrosome reaction and subsequent membrane fusion events.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Male infertility (sperm-egg fusion defect) | Loss of SPESP1 function disrupts equatorial segment integrity, preventing sperm-egg fusion | Mouse knockout models show infertility; human variants associated with fertilization failure |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 12.5 | High |
| Fallopian tube | 0.2 | Not detected |
| Prostate | 0.1 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Spermatozoa | N/A | High expression in mature sperm |
| Testicular germ cells | N/A | Expressed in spermatids |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Missense | Rare | Potential loss of start codon, likely loss of function |
| c.100C>T (p.Arg34*) | Nonsense | Rare | Premature stop, loss of function |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations in SPESP1 are predicted to cause loss of function, leading to impaired sperm-egg fusion.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported.
View complete mutation data：
Gene Ontology (GO)
| • single fertilization (GO:0007338) | • acrosome reaction (GO:0007340) |
| • sperm-egg fusion (GO:0035036) | • plasma membrane (GO:0005886) |
| • acrosomal vesicle (GO:0001669) |
Pathways
• Fertilization (Reactome: R-HSA-1187000)
• Sperm-egg fusion (KEGG: map04916)
Protein Summary
SPESP1 is a 267-amino acid protein with a signal peptide and a transmembrane domain. It is localized to the equatorial segment of the sperm head, where it mediates membrane fusion between sperm and egg. The protein undergoes post-translational modifications including glycosylation and proteolytic processing during capacitation.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SPESP1 Knockout HEK293 Cell Line | EDJ-KQ11557 | Human | 246777 | Details Get a Quote |
| SPESP1 Knockout HeLa Cell Line | EDJ-KQ59234 | Human | 246777 | Details Get a Quote |
| SPESP1 Knockout A-549 Cell Line | EDJ-KQ67702 | Human | 246777 | Details Get a Quote |
| SPESP1 Knockout HCT 116 Cell Line | EDJ-KQ76084 | Human | 246777 | Details Get a Quote |
