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bioRxiv · 10.1101/405407

Effects of P16 DNA Methylation on Proliferation, Senescence, and Lifespan of Human Fibroblasts

Gan, Y.·Cui, C.·Xiang, S.·Zhang, B.·Deng, D.
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Abstract

The aim is to study the effects of P16 DNA methylation on lifespan of normal cells. An expression-controllable pTRIPZ vector expressing P26-specific zinc finger binding protein-based methyltransferase (P16-Dnmt) was used to induce P16 methylation in primary CCD-I8C0 fibroblasts via stable transfection. Long-term dynamic IncuCyte analysis showed that CCD-I8C0 fibroblasts expressing baseline P16-Dnmt continued proliferating until passage-26 in the 53th post-transfection week, while vector control cells stopped proliferating at passage-6 and completely died 2 weeks later. The proliferation rate of baseline P16-Dnmt cells was significantly higher than that of vector control cells. The proportion of P-galactosidase-positive staining cells was significantly decreased in baseline P16-Dnmt cells compared to vector control cells. The P16 expression was lost in baseline P16-Dnmt cells at and after passage-6. The average telomere length in baseline P16-Dnmt cells also gradually decreased. In conclusion, P16 methylation could prevent senescence, promote proliferation, and expand lifespan of human fibroblasts, which may play a role in cancer development.\n\nSummaryA zinc finger protein-based DNA methyltransferase (P16-Dnmt) expressed at the baseline level could specifically methylate P16 promoter CpG islands. P16 methylation induced by baseline P16-Dnmt could significantly prevent senescence, promote proliferation, and expand lifespan of primary human fibroblasts.

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Gan, Y., Cui, C., Xiang, S., Zhang, B., Deng, D.. 2018-08-30. Effects of P16 DNA Methylation on Proliferation, Senescence, and Lifespan of Human Fibroblasts. https://doi.org/10.1101/405407

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