The Polycomb group proteins bind throughout the INK4A-ARF locus and are disassociated in senescent cells
AP Bracken, D Kleine-Kohlbrecher… - Genes & …, 2007 - genesdev.cshlp.org
Genes & development, 2007•genesdev.cshlp.org
The p16INK4A and p14ARF proteins, encoded by the INK4A-ARF locus, are key regulators
of cellular senescence, yet the mechanisms triggering their up-regulation are not well
understood. Here, we show that the ability of the oncogene BMI1 to repress the INK4A-ARF
locus requires its direct association and is dependent on the continued presence of the
EZH2-containing Polycomb-Repressive Complex 2 (PRC2) complex. Significantly, EZH2 is
down-regulated in stressed and senescing populations of cells, coinciding with decreased …
of cellular senescence, yet the mechanisms triggering their up-regulation are not well
understood. Here, we show that the ability of the oncogene BMI1 to repress the INK4A-ARF
locus requires its direct association and is dependent on the continued presence of the
EZH2-containing Polycomb-Repressive Complex 2 (PRC2) complex. Significantly, EZH2 is
down-regulated in stressed and senescing populations of cells, coinciding with decreased …
The p16INK4A and p14ARF proteins, encoded by the INK4A-ARF locus, are key regulators of cellular senescence, yet the mechanisms triggering their up-regulation are not well understood. Here, we show that the ability of the oncogene BMI1 to repress the INK4A-ARF locus requires its direct association and is dependent on the continued presence of the EZH2-containing Polycomb-Repressive Complex 2 (PRC2) complex. Significantly, EZH2 is down-regulated in stressed and senescing populations of cells, coinciding with decreased levels of associated H3K27me3, displacement of BMI1, and activation of transcription. These results provide a model for how the INK4A-ARF locus is activated and how Polycombs contribute to cancer.
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