Skip to main content
. 2016 Feb 22;15(7):919–930. doi: 10.1080/15384101.2016.1149272

Figure 1.

Figure 1.

The G1-S phase transition is perturbed in teratoma-susceptible gonocytes. Dysregulation of the G1-S phase checkpoint in gonocytes increased with teratoma risk. (A) Oct4::GFP transgenic FVB (teratoma-resistant), 129 (low teratoma risk), and M19 (high teratoma risk) embryonic testes were sectioned and immunostained for phospho-pRB1 (E13.5, E14.5, E15.5). GFP-positive germ cells, positive and negative for phospho-pRB1, were counted. Data are plotted as the percentage of germ cells positive for phospho-pRB1 ± SEM (n = 7-11). ‡, P < 0.001; #, P < 0.0001. (B) Confocal microscopy images of E15.5 testes immunostained for phospho-pRB1. At E15.5, FVB germ cells are phospho-pRB1-negative, but some M19 germ cells remain phospho-pRB1-positive. Small groups of phospho-pRB1-positive germ cells are noted (arrowheads). Scale bar: 50 μm. (C) Confocal microscopy images of an E15.5 M19 testis sectioned and immunostained for CCND1 and the proliferative marker KI67. All KI67-positive gonocytes were also positive for CCND1; small groups are noted (white arrowheads). However, several CCND1-positive gonocytes were KI67-negative; small groups are noted (yellow arrowheads). Scale bar: 50 μm.