... of quiescence is known to occur in prospermatogonia prior to postnatal spermatogonial transition, the importance of this has not been defined. Here, using mouse models with conditional knockout of the master cell cycle regulator Rb1 to disrupt normal timing of the quiescence period, we found that failure...

... as a model, we found that spermatogonia and precursor prospermatogonia exhibit a heterogeneous capacity to respond to RA with at least two underlying causes. First, progenitor spermatogonia are prevented from responding to RA by catabolic activity of cytochrome P450 family 26 enzymes. Second, a smaller...

...-spermatogonia before birth( Szabo and Mann, 1995 ; Ueda et al., 2000 ; Surani, 2001 ; Hajkova et al., 2002 ). Therefore, the characteristics of PGCs change during development before they mature into postnatal germ cells. Germ cell Epiblast Primordial Germ Cell (PGC) Prospermatogonia Spermatogonia...