FIGURE 3.

Expression and localization of SPATA1 in male germ cells of wild-type mice. A, Testicular expression of SPATA1 during the first wave of spermatogenesis analyzed by Western blotting. Notice that SPATA1 was detected from day 24 after birth, and the expression level was higher at day after day 30. B, IFT20 and SPATA1 were present in the same complex in mouse testis. Testicular extract was pulled down with an anti-SPATA1 antibody and Western blotting was conducted using anti-IFT20 antibody. IFT20 was pulled down by the anti-SPATA1 antibody. C, Examination of SPATA1 localization in isolated male germ cells by immunofluorescence staining. SPATA1 (red signals, white arrows) was co-localized with an acrosomal marker, Sp56 (green signals) in the acrosomal region of spermatids. D, Immunofluorescence analysis of SPATA1 protein in early stages of testicular germ cells. The protein is localized in the acrosome of germ cells from stages I to III. E, Representative image of localization of IFT20 and peanut-lectin in a round spermatid. The isolated male germ cells were double-stained with an anti-IFT20 antibody and fluorescence labeled peanut-lectin. Notice that IFT20 was partially co-localized with peanut-lectin (white arrow). Most IFT20 signal was on the top of lectin