Increased senescence in <i>Rplp1</i>-deleted primary MEFs is mediated by the p16^INK4A/pRb pathway.

<p>(<b>A</b>) Quantification of the cell cycle profiles of control and <i>Rplp1ⁱ</i>^Δ pMEFs that were untreated or treated for 4 days with 4-OHT. Student's t-test was applied for the statistical analysis. n.s.: not significant. Error bars: SEM. N = 3. (<b>B</b>) <i>Rplp1</i>^iΔ and control pMEFs were treated with 1 µM 4-OHT for 4 days or left untreated. The cells were harvested, stained with Annexin V/DAPI and analyzed by flow cytometry on day 4 after the treatment (Day 4), or 3 days later (Day 7). Error bars: SEM. (<b>C</b>) β-galactosidase staining was performed in <i>Rplp1ⁱ</i>^Δ and control pMEFs that were treated with 1 µM 4-OHT for 4 days or left untreated. (<b>D</b>) Quantification of the amount of β-gal⁺ cells for each analyzed clone analyzed. (<b>E and F</b>). Western blot analysis of protein extracts from <i>Rplp1</i>^iΔ and control pMEFs that were treated with 1 µM 4-OHT for 4 days or left untreated.