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Updated: Jan 24, 2026

Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
Published on: May 22, 2013
PES1 is a critical component of telomerase assembly and regulates cellular senescence
Long Cheng1, Bin Yuan1,2, Sunyang Ying1
1Department of Medical Molecular Biology, Beijing Institute of Biotechnology, Collaborative Innovation Center for Cancer Medicine, Beijing 100850, China.
Abstract:
Telomerase defers the onset of telomere shortening and cellular senescence by adding telomeric repeat DNA to chromosome ends, and its activation contributes to carcinogenesis. Telomerase minimally consists of the telomerase reverse transcriptase (TERT) and the telomerase RNA (TR). However, how telomerase assembles is largely unknown. Here, we demonstrate that PES1 (Pescadillo), a protein overexpressed in many cancers, forms a complex with TERT and TR through direct interaction with TERT, regulating telomerase activity, telomere length maintenance, and senescence. PES1 does not interact with the previously reported telomerase components Reptin, Pontin, p23, and Hsp90. PES1 facilitates telomerase assembly by promoting direct interaction between TERT and TR without affecting TERT and TR levels. PES1 expression correlates positively with telomerase activity and negatively with senescence in patients with breast cancer. Thus, we identify a previously unknown telomerase complex, and targeting PES1 may open a new avenue for cancer therapy.
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