The chromosome ends of embryonic stem cells are protected by their own unique strategy
CCR scientists have discovered that embryonic stem cells protect their telomeres in a unique manner. Telomeres are the structures located at the ends of the chromosomes which shorten each time a cell divides. The research team, led by Eros Denchi, Ph.D. (NIH Stadtman investigator at CCR’s Laboratory of Genomic Integrity), found that embryonic stem cells use genes normally used during the earliest stages of development in order to prevent unwanted DNA repair. The findings of the team, based on studies of mouse embryonic cells, will be published in Nature, November 25, 2020.
The new findings, by revealing a surprising way that cells can protect their own telomeres may help to explain the survival strategy used by some cancerous cells. These cells must find a means of circumventing the growth limitations imposed by the shortening telomeres as we age.
The embryonic stem cells that arise in the early stages of an embryonic development have the unique ability to transform into virtually any type of specialized cell. Lazzerini Denchi, along with her colleagues, discovered that cells could survive without the protein TRF2, which protects and binds chromosome ends. This protein is essential to hundreds of types of cells. It is essential for the repair of DNA damage. Without it, exposed ends of chromosomes trigger the activation faulty pathways that stitch them together. The chromosomes fusion together and the cells lose their ability to divide. When Lazzerini Denchi’s team removed TRF2 in embryonic stem cell, the chromosomes retained their integrity and cells continued to multiply.
Source:
https://medicalxpress.com/news/2020-11-embryonic-stem-cells-strategy-chromosome.html
