# age: E3-ubiquitin ligases, the 'garbage disposal system' and the cell immortality

<< Human embryonic stem cells are considered to be immortal: they do not age, they can proliferate indefinitely >>

<< One of the mechanisms underlying immortality is the 'garbage disposal system' known as the proteasome >>

<< Of key relevance in the proteasome system are the so-called E3-ubiquitin ligases >>

AA << screened more than 600 proteins systematically and narrowed it down to 30 E3 ligases of special interest >>

AA << found that a global reduction in the proteolytic activity affects many intrinsic characteristics of embryonic stem cells, providing a link between immortality and up-regulated protein degradation >>

University of Cologne. On the immortality of stem cells. Mar 7, 2018.

https://m.phys.org/news/2018-03-immortality-stem-cells.html

Isabel Saez, Seda Koyuncu, et al. Insights into the ubiquitin-proteasome system of human embryonic stem cells. Scientific Reports. 2018; 8 (4092). doi: 10.1038/s41598-018-22384-9.     Mar 6, 2018.
   
https://www.nature.com/articles/s41598-018-22384-9