Gene Information
Gene NameSPAG8
OrganismHomo sapiens (Human)
Gene Length485
Protein NamesSperm-associated antigen 8 (HSD-1) (Sperm membrane protein 1) (SMP-1) (Sperm membrane protein BS-84)
Target NameNA
Target TypeNA
Gene Age987 ( ENSG00000137098 )
Evolutionary StageMammalia
AlphaFoldDBQ99932
Gene CardSPAG8
Uniprot IDQ99932
PfamNA
In ASDno
Allosteric Predictionno (-1.413408779)
Ortholog in AnimalsAlpaca_ SPAG8 ( ortholog_one2one )
Dog_ SPAG8 ( ortholog_one2one )
Macaque_ SPAG8 ( ortholog_one2one )
Mouse_ Spag8 ( ortholog_one2one )
Pig_ SPAG8 ( ortholog_one2one )
Rat_ Spag8 ( ortholog_one2one )
Rabbit_ SPAG8 ( ortholog_one2one )
OhnologsNA
ParalogsNA
Tissueoviduct, testis
Tissue SpecificityExpressed in testis (germ cells), but not in liver, kidney, prostate and small intestine. {ECO:0000269|PubMed:8788182}.
Pharmacological Animal ModelsNA
Gene Ontology
(biological process)
Gene Ontology
(cellular component)
Gene Ontology
(molecular function)
PDB NA 
DBSNP rs13299596  rs17851728 
Subcellular location [CC]Cytoplasm {ECO:0000250|UniProtKB:Q3V0Q6}. Nucleus {ECO:0000250|UniProtKB:Q3V0Q6}. Cytoplasmic vesicle, secretory vesicle, acrosome {ECO:0000269|PubMed:15014887, ECO:0000269|PubMed:17187156, ECO:0000269|PubMed:8788182}. Cytoplasm, cytoskeleton, microtubule organizing center {ECO:0000269|PubMed:19548270}. Cytoplasm, cytoskeleton, spindle {ECO:0000269|PubMed:19548270}. Cytoplasm, cytoskeleton, cilium axoneme {ECO:0000250|UniProtKB:E1BNS6}. Note=In mature sperm cells, detected in the acrosomal region of the head and in the middle piece of the tail (By similarity). Localized to the nucleus and cytoplasm of spermatocytes and round spermatids while, in elongating spermatids, expressed in the cytoplasm but not in the nucleus (By similarity). During the cell cycle, localized on the microtubule-organizing center (MTOC) during prophase. In metaphase, extends along spindle microtubules. In anaphase, detected on the astral microtubules and mid-zone. In telophase, remains at the mid-zone. After cytokinesis, returns to the MTOC (PubMed:19548270). Microtubule inner protein (MIP) part of the dynein-decorated doublet microtubules (DMTs) in cilia axoneme (By similarity). {ECO:0000250|UniProtKB:E1BNS6, ECO:0000250|UniProtKB:Q3V0Q6, ECO:0000269|PubMed:19548270}.
Mouse PG classificationNA
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