"Telomerase is a cellular enzyme that adds telomeric DNA sequences to the ends of chromosomes, aiding in preserving genome stability."
BUFFALO, NY — May 5, 2026 — A new research paper was published in Volume 18 of Aging-US on April 13, 2026, titled " Cross species activity of TERT human telomerase component ."
The study was led by co–first authors Raúl Sánchez-Vázquez and Paula Martínez, with María A. Blasco serving as corresponding author, from the Spanish National Cancer Centre (CNIO), Madrid, Spain . In this study, the researchers explored a key question in aging and regenerative medicine: can the human telomerase protein function effectively in other species commonly used in preclinical research? Telomerase plays a central role in maintaining chromosome integrity by preventing telomere shortening—a process closely linked to cellular aging and disease.
To investigate this, the team introduced the human telomerase catalytic subunit (TERT) into primary lung fibroblasts from several mammalian species, including monkey, pig, rabbit, rat, dog, and mouse. They then assessed both biochemical activity and the ability of telomerase to extend telomeres over time.
The results revealed a clear distinction between biochemical compatibility and true biological function. In vitro, human TERT was able to form active complexes with telomerase RNA from several species, including monkey, pig, rabbit, and rat. However, this activity did not always translate into effective telomere maintenance in living cells.
Notably, only human and non-human primate cells showed progressive telomere lengthening over time. In contrast, other species—even those showing initial enzymatic activity—failed to sustain telomere extension during long-term culture. In some cases, telomeres continued to shorten, suggesting that functional integration of telomerase depends on additional species-specific factors.
The study also uncovered important limitations in commonly used animal models. Mouse and canine cells did not support human TERT activity, and in some cases, expression of the human enzyme led to reduced cell viability and signs of cellular stress.
"These results reveal that only non-human primate cells support full functional activity of the human telomerase protein in a cellular context, underscoring their suitability as preclinical models for telomerase-based therapeutic strategies."
Importantly, the findings highlight that successful telomerase activity in a test tube does not necessarily reflect what happens inside a living cell. The recruitment, regulation, and function of telomerase depend on a complex network of interacting proteins and cellular processes, many of which differ across species.
Overall, this study provides important insight into the challenges of translating telomerase-based therapies from preclinical models to humans. By identifying non-human primates as the most compatible system, the work offers a clearer path forward for developing therapies aimed at treating telomere-related diseases and age-associated conditions.
Paper DOI: https://doi.org/10.18632/aging.206372
