Figure 2.

The Styx reporter allele is differentially expressed during spermiogenesis of mouse spermatids. (A) β-gal staining of whole adult testis from wild-type and heterozygous males. (Scale bar, 2 mm.) (B) β-gal-stained cryosections of testicular seminiferous tubules (above). The approximate developmental staging (C) of tubules (roman numerals) and spermatids (arrows) are indicated. (Scale bar, 50 μm.) (C) Selected section of Styx^± seminiferous tubule (Left) and schematic representation of the relative position of cellular cohorts in normal mouse tubule stages IV and IX (Right; refs. 20 and 24). The arrows indicate the direction of gamete differentiation from intermediate spermatogonia (In), through leptotene (L) and pachytene (P) spermatocytes, into spermatids: round (step 4), elongating (step 9), and condensed (step 15). A somatic Sertoli cell (S) is shown relative to the germ cell layers.