Disrupted lens fiber cell denucleation and protein aggregation in postnatal dominant-negative (dn) Brg1 eyes. Histological lens midsections were obtained from wild-type (A-E) and transgenic mice (F-J) from postnatal stages (days P1, P7, P21 and P90). Wild-type lenses gradually develop organelle-free zones (OFZs) from the center of the lens, but dnBrg1 transgenic lens fiber cell nuclei remain in the differentiated lens fiber cells (F and G) and are particularly evident at the lens transitional zones (G and H). Lens protein aggregation was evident in day P21 (I) and day P90 (J) transgenic animals. Grossly distorted lens structure (J) was observed in the Brg1DN ocular system at day P90. L, lens; T, lens transitional zone.