Immunocytochemical Localization of an H2A Variant in the Spermatogenic Cells of the Mouse

Immunocytochemical localization of protein "A," an H2A variant, has been carried out in the adult, neonatal, and embryonic spermatogenic cells of the mouse using the peroxidase-antiperoxidase technique. The results indicate an apparent enrichment of this protein in the meiotic cells of the adult testis. In addition, T-prospermatogonia present in the neonatal mouse and 16-day-old embryos were found to be immunoreactive. By contrast, Sertoli cells and other somatic elements of the neonatal and embryonic gonads were only weakly immunoreactive. These data suggest potential usefulness of protein "A" as a nuclear marker of the embryonic spermatogenic cells.