Miniaturized Telomerase Assays Reveal Novel Inhibitor Interactions:

Telomerase reverse transcriptase (TERT) plays a central role in cellular development, regeneration, and cancer biology. Because abnormal telomerase activity is linked to tumor progression and age‑related diseases, researchers have long sought reliable ways to identify compounds that can modulate its function. Traditional assays, however, are limited in throughput and reproducibility. This study set out to develop a highly miniaturized, microarray‑based platform to screen for telomerase‑binding compounds more efficiently and with greater sensitivity.

Nano-Plotter users immobilized recombinant telomerase proteins (from E. coli) and telomerase from human cancer cell lysates onto nitrocellulose microarrays using GeSiM’s non‑contact microarray spotter technology. This precise deposition allowed the creation of highly reproducible arrays with minimal sample volumes. Fluorescently labeled primers and nucleotides were then used to detect binding interactions, and complementary techniques such as microscale thermophoresis and AlphaFold3 modeling were applied to validate binding affinities and predict structural interactions.

The assay successfully identified binding of known telomerase inhibitors, such as EGCG, and revealed an unexpected interaction with a cytochalasin derivative (4′‑iodo‑cytochalasin H). This compound showed unusual binding behavior, interfering with telomerase’s RNA template association. Importantly, the microarray format achieved high sensitivity, requiring only picoliter volumes per spot, and enabled thousands of measurements from a single sample. The immobilized proteins remained stable for weeks, underscoring the robustness of the platform.

This work demonstrates that microarray‑based assays can serve as powerful tools for telomerase research, offering scalability, reproducibility, and sensitivity far beyond conventional methods. The discovery of atypical binding by a cytochalasin derivative highlights the potential of this platform to uncover novel inhibitors with therapeutic relevance.

Development of a microarray based binding assay monitoring TERT activity.

This article is based on the following publication: Ye, J.L., Fan, L., Bär, C. et al. Development of a microarray based telomerase binding assay reveals unusual binding of a cytochalasin derivative. Sci Rep 15, 19515 (2025). https://doi.org/10.1038/s41598-025-00230-z