How stem cells keep telomeres in check

• Published in: Differentiation (London) Vol. 100; pp. 21 - 25
• Main Authors: Li, Julia Su Zhou, Denchi, Eros Lazzerini
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01.03.2018; Elsevier Science Ltd
• Subjects: Animals; Cell cycle; Cell proliferation; Cell self-renewal; Chromosomes; Clonal deletion; DNA damage; Humans; Pluripotency; Pluripotent Stem Cells - cytology; Pluripotent Stem Cells - metabolism; Proteins; Shelterin; Stem cells; Telomerase; Telomere; Telomere - genetics; Telomere - metabolism; Telomere Homeostasis; Telomere trimming; Telomere-Binding Proteins - genetics; Telomere-Binding Proteins - metabolism; Telomeres; TZAP; ZBTB48; TZAP; Telomere trimming; Telomere; Stem cells; Shelterin; ZBTB48
• ISSN: 0301-4681; 1432-0436
• DOI: 10.1016/j.diff.2018.01.004

In multicellular organisms, regulation of telomere length in pluripotent stem cells is critical to ensure organism development and survival. Telomeres consist of repetitive DNA that are progressively lost with each cellular division. When telomeres become critically short, they activate a DNA damage response that results in cell cycle arrest. To counteract telomere attrition, pluripotent stem cells are equipped with telomere elongation mechanisms that ensure prolonged proliferation capacity and self-renewal capacity. Excessive telomere elongation can also be deleterious and is counteracted by a rapid telomere deletion mechanism termed telomere trimming. While the consequences of critically short telomeres are well established, we are only beginning to understand the mechanisms that counteract excessive telomere elongation. The balance between telomere elongation and shortening determine the telomere length set point in pluripotent stem cells and ensures sustained proliferative potential without causing chromosome instability. •Regulation of telomere length in stem cells.•Upper Limit of Telomere Length.•Mechanisms of telomere trimming.