p16INK4a induces an age-dependent decline in islet regenerative potential

  title={p16INK4a induces an age-dependent decline in islet regenerative potential},
  author={Janakiraman Krishnamurthy and Matthew R. Ramsey and Keith L. Ligon and Chad D. Torrice and A. Koh and Susan Bonner-Weir and Norman E. Sharpless},
The p16INK4a tumour suppressor accumulates in many tissues as a function of advancing age. p16INK4a is an effector of senescence and a potent inhibitor of the proliferative kinase Cdk4 (ref. 6), which is essential for pancreatic β-cell proliferation in adult mammals. Here we show that p16INK4a constrains islet proliferation and regeneration in an age-dependent manner. Expression of the p16INK4a transcript is enriched in purified islets compared with the exocrine pancreas, and islet-specific… 

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