SPACA1 is a membrane protein that localizes in the equatorial segment of spermatozoa in mammals and is reported to function in sperm-egg fusion. Disruption of Spaca1 led to the disappearance of the nuclear plate, a dense lining of the nuclear envelope facing the inner acrosomal membrane. This coincided with the failure of acrosomal expansion during spermiogenesis and resulted in the degeneration and disappearance of the acrosome in mature spermatozoa. SPACA1-deficient male mice are infertile.
Fig.1 Western blotting of mouse testis extracts of wild-type and Spaca1 knockout mice with anti-SPACA1 antibody. 20 µg of Triton X-100 extracts from testes of wild type (+/+), Spaca1 single (+/-) and double (-/-)knock-out mice was reacted with anti-SPACA1 antibody at 1/1,000 dilution. Basigin was used as a loading control.
Fig.2 Immunofluorescence staining of SPACA1 in step 7 round spermatids. Spaca1 protein in 7 round spermatids was reacted with anti-SPACA1 antibody and as a secondary antibody, Alexa-Fluor 488 conjugated anti-rabbit IgG antibody (green) was used. DNA was stained with Hoechst 33258.
# Fujihara Y., et al. SPACA1-deficient male mice are infertile with abnormally shaped
sperm heads reminiscent of globozoospermia. Development. 2012 Oct;139(19):3583-9. PMID: 22949614
To be used for research only. DO NOT use for human gene therapy or clinical diagnosis.