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Telomeres and Telomerase

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Related Experiment Video

Updated: Jun 3, 2026

Observation and Quantification of Telomere and Repetitive Sequences Using Fluorescence In Situ Hybridization (FISH) with PNA Probes in Caenorhabditis elegans

Observation and Quantification of Telomere and Repetitive Sequences Using Fluorescence In Situ Hybridization (FISH) with PNA Probes in Caenorhabditis elegans

Published on: August 4, 2016

Visualization of human telomerase localization by fluorescence microscopy techniques.

Eladio Abreu¹, Rebecca M Terns, Michael P Terns

¹Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA.

Methods in Molecular Biology (Clifton, N.J.)

|April 5, 2011

Summary

Human telomerase ribonucleoprotein (RNP) localization to telomeres is cell cycle-regulated. This study visualizes human telomerase RNA (hTR) trafficking between Cajal bodies and telomeres using fluorescence microscopy.

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Semi-quantitative Detection of RNA-dependent RNA Polymerase Activity of Human Telomerase Reverse Transcriptase Protein

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Published on: June 12, 2018

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Last Updated: Jun 3, 2026

Observation and Quantification of Telomere and Repetitive Sequences Using Fluorescence In Situ Hybridization (FISH) with PNA Probes in Caenorhabditis elegans

Observation and Quantification of Telomere and Repetitive Sequences Using Fluorescence In Situ Hybridization (FISH) with PNA Probes in Caenorhabditis elegans

Published on: August 4, 2016

Semi-quantitative Detection of RNA-dependent RNA Polymerase Activity of Human Telomerase Reverse Transcriptase Protein

Semi-quantitative Detection of RNA-dependent RNA Polymerase Activity of Human Telomerase Reverse Transcriptase Protein

Published on: June 12, 2018

Area of Science:

Molecular Biology
Cell Biology
Genetics

Background:

Human telomerase is a ribonucleoprotein (RNP) essential for maintaining telomere length and genome stability.
It consists of telomerase RNA (hTR) and telomerase reverse transcriptase (hTERT).
Intracellular trafficking of telomerase regulates its activity, with movement between Cajal bodies and telomeres linked to the cell cycle.

Purpose of the Study:

To describe fluorescence microscopy methods for visualizing the subcellular localization of human telomerase RNA (hTR).
To investigate the trafficking of hTR relative to Cajal bodies and telomeres in cultured human cells.
To synchronize and analyze cells during S phase, when telomerase localizes to telomeres.

Main Methods:

Fluorescence in situ hybridization (FISH) to detect hTR and telomeric DNA.
Immunofluorescence (IF) to detect Cajal bodies and telomere-binding proteins.
Cell cycle synchronization to isolate cells in S phase for analysis.

Main Results:

Successful visualization of hTR subcellular localization relative to Cajal bodies and telomeres.
Demonstration of cell cycle-dependent trafficking of hTR to telomeres during S phase.
Establishment of methods to study telomerase dynamics in human cells.

Conclusions:

Subcellular localization and trafficking of hTR are critical for telomerase function.
Telomerase activity is tightly regulated by its cell cycle-dependent movement to telomeres.
The described fluorescence microscopy techniques provide valuable tools for studying telomerase biology.