Spermatogenesis And Centriole Associated Protein 1 (SPATC1)

The deduced 480-amino acid mouse protein has a calculated molecular mass of 51.4 kD and contains an N-terminal leucine zipper motif. Northern blot analysis detected Spatc1 expression exclusively in mouse testis. Western blot analysis detected Spatc1 in the insoluble fraction of testis tissue. Immunohistochemical analysis detected Spatc1 in discrete spots in the cytoplasm of pachytene spermatocytes, spermatocytes undergoing meiotic division, round spermatids, and condensed spermatids. Spatc1 colocalized with the centrosomal protein pericentrin (PCNT1). Studies with deletion mutants expressed in BALB/3T3 cells showed that centrosomal localization requires the N-terminal leucine zipper domain. Spatc1 localized to the cytoplasmic face of a nonmembranous component, such as the centrosome.