The correlation of anti-sperm antibodies with cases of unexplained infertility implicates a role for these antibodies in blocking fertilization. Improved diagnosis and treatment of immunologic infertility, as well as identification of proteins for targeted contraception, are dependent on the identification and characterization of relevant sperm antigens. The protein expressed by this gene is recognized by anti-sperm agglutinating antibodies from an infertile woman. Furthermore, immunization of female rats with the recombinant human protein reduced fertility. This protein localizes to the plasma membrane of germ cells in the testis and to the post-acrosomal plasma membrane of mature spermatozoa. Recombinant polypeptide binds GTP and exhibits GTPase activity. Thus, this protein may regulate GTP signal transduction pathways involved in spermatogenesis and fertilization. Two transcript variants of this gene encode the same protein. [provided by RefSeq, Jul 2008]
Transcription factors with Perturb-seq knockdown data for SPAG1. The Binding column indicates whether any binding evidence exists for this TF–gene pair (ChIP-seq or motif footprint peaks). The Mean coef is the average Perturb-seq regression coefficient across active gRNAs (positive = SPAG1 upregulated upon KD; negative = downregulated). The Outlier column indicates whether this gene is in the top or bottom 5% of all TF knockdown effects.
| TF | Mean coef | Binding | Outlier | TF→Gene link |
|---|
Open chromatin peaks (ATAC-seq) in the genomic neighbourhood of SPAG1, linked by TSS proximity or chromatin conformation (Multiome / HiCAR). Each element overlaps at least one TF ChIP-seq binding site — the TFs column shows how many distinct TFs bind that element.
| Accessibility | Element | Dist. to TSS | Link type | TFs |
|---|---|---|---|---|
| chr8:99,892,915–99,894,104 | 264.4 kb | Distal (>10kb) Multiome | 817 | |
| chr8:100,145,361–100,146,165 | 12.2 kb | Distal (>10kb) Multiome | 584 | |
| chr8:100,149,973–100,150,933 | 7.5 kb | Proximal (<10kb) Multiome | 732 | |
| chr8:100,157,695–100,158,647 | 155 bp | At TSS Multiome | 728 | |
| chr8:100,212,742–100,213,750 | 55.1 kb | Distal (>10kb) Multiome | 792 | |
| chr8:100,309,111–100,310,745 | 152.1 kb | Distal (>10kb) Multiome | 964 | |
| chr8:100,335,686–100,336,642 | 178.2 kb | Distal (>10kb) Multiome | 284 | |
| chr8:100,375,327–100,376,046 | 217.7 kb | Distal (>10kb) Multiome | 241 | |
| chr8:100,559,150–100,560,136 | 401.7 kb | Distal (>10kb) Multiome HiCAR | 918 |
Genomic view of the SPAG1 locus showing ATAC-seq accessibility and RNA-seq expression across the ESC → DE time course, together with TF binding peaks and element-to-TSS loop connections.