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Updated: Jan 10, 2026
08:26
Semi-quantitative Detection of RNA-dependent RNA Polymerase Activity of Human Telomerase Reverse Transcriptase Protein
Published on: June 12, 2018
10.4K
Antiviral reverse transcriptases reveal the evolutionary origin of telomerase
Stephen Tang1, Josephine L Ramirez1, Mario Rodríguez Mestre2
1Department of Biochemistry and Molecular Biophysics, Columbia University; New York, NY, USA.
Biorxiv : the Preprint Server for Biology
|November 24, 2025
Summary
Researchers discovered a new bacterial antiviral system, DRT10, which uses a noncoding RNA (ncRNA) to synthesize DNA. This system shares surprising similarities with telomerase, suggesting a potential bacterial origin for telomerase.
Area of Science:
- Molecular Biology
- Microbiology
- Virology
Background:
- Bacteria possess defense-associated reverse transcriptases (DRTs) for antiviral protection.
- The diversity and mechanisms of many DRTs remain largely unexplored.
Purpose of the Study:
- To identify and characterize novel DRT systems and their mechanisms.
- To investigate the evolutionary relationship between bacterial antiviral systems and other reverse transcriptases.
Main Methods:
- Identification of a new DRT system, termed DRT10.
- Analysis of DRT10's association with noncoding RNA (ncRNA) in DNA synthesis.
- Phylogenetic analysis of reverse transcriptases (RTs) across life domains.
- Structural and mechanistic comparisons between DRT10 and telomerase.
Main Results:
- DRT10 catalyzes processive, protein-primed synthesis of tandem-repeat DNA.
- The ncRNA component of DRT10 dictates repeat addition through sequence and structural features.
- Phylogenetic and structural data reveal an unexpected evolutionary link between DRT10 and telomerase.
Conclusions:
- DRT10 expands the known mechanisms of reverse transcription in bacterial antiviral defense.
- Findings suggest a potential bacterial origin for telomerase, challenging previous evolutionary models.
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