FIG. 5.

Incomplete deletion of the Ppp1cc gene in testis led to mosaic expression of the PPP1CC2 isoform within testis and seminiferous tubules. Immunohistochemistry (IHC) and confocal imaging was performed to observe the PPP1CC2 expression pattern within the testis of GcKO animals. a, b, and c) In a vast majority of the tubules, the PPP1CC2 signal was absent, as observed under 20× magnification. However, it is to be noted that among a small population of tubules, the PPP1CC2 signal (denoted by white arrowhead) was retained, giving rise to a mosaic pattern of expression in the GcKO testis. Magnification at 40× (e, f, and g) reveals a patchy expression of PPP1CC2 within these tubules derived from clonal populations of germ cells that escaped Ppp1cc deletion, compared to control (d and h). Arc (arrowhead) denotes the region of germinal epithelium that is negative or has a very low level of PPP1CC2 signal. Depending on the efficacy of the recombination, these negatively stained regions vary from three quarters (e) to one quarter (f) to half (g) of the tubule. d, d', h, and h') It is to be noted that control animals had uniform PPP1CC2 expression from early pachytene spermatocytes to elongating spermatids (denoted by double-headed arrows). a', b', c', and d') The corresponding DIC images of a, b, c, d, respectively. e', f', g', and h') These images are derived by overlaying the corresponding DAPI-counterstained images on e, f, g, and h, respectively. All images are representative of multiple sections from different animals.