Figure 6.

BrdU incorporation in RGCs, but not in retinal precursors, is independent of Cdk4/6 activity. (A) The selective Cdk4/6 inhibitor PD 0332991, used at 400 nM, prevents the capacity of E6 retinal precursor cells to incorporate BrdU after a short pulse (30 min). The analysis was performed after 20 h of inhibitor treatment. (B) RGC-enriched retinal cultures were lipofected with Luc-i, 1p27i, or 2p27i vectors and treated with 0.5 mg/ml BrdU for 20 h in the presence (+) or absence (−) of 400 nM PD 0332991. BrdU incorporation was evaluated in Brn3a-positive cells (a subpopulation of RGCs). (C) RGC-enriched retinal cultures treated as described above. BrdU incorporation was evaluated in cells that display RGC morphology (monoaxonic cells with round cytoplasm). *P < 0.01; **P < 0.005; ***P < 0.001 (Student´s t test, n = 3).