What mechanisms are responsible for telomere shortening in non-dividing cells?
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By Darko Savic on Jul 26, 2020
Do we know what mechanisms are responsible for the telomere shortening in post-mitotic (non-dividing) cells? Especially neurons, since they have been studied in more detail than other cell types in this regard.
If it's still not known, could we come up with experiments to find out?
Re-induction of cell cycle and oxidative stress
A number of mechanisms for cell cycle-independent telomere shortening have been proposed: 1. In post-mitotic neurons, the observation of a variation in the DNA content suggested that there might be cell-cycle re-induction in about 10-20% of the neurons. Studies I found were speculative and we currently do not know the actual proportion of neurons (or other cells that were previously known to be non-dividing) that are (or can be, under certain circumstances) re-induce their cell cycle. This number can be greater than 20%, significant enough to observe telomere shortening at the tissue level. Reference: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6286833/ 2. Secondly, oxidative stress leads to telomere shortening in non-replicative cells. Do check Figure 1 from (https://www.mdpi.com/2073-4425/7/9/58/htm)
by Shubhankar Kulkarni on Jul 28, 2020