GO:0001172 RNA-templated transcription: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0001172 RNA-templated transcription is defined as the synthesis of an RNA transcript from an RNA template.
• It is a biological_process that is distinct from canonical DNA-templated transcription and is used by RNA viruses, viroids, and some cellular enzymes [1,2].
• Key experimental systems include potato spindle tuber viroid (PSTVd) and hepatitis delta virus (HDV), where RNA-templated transcription is catalyzed by host RNA polymerases [1,2,7].
• The process is implicated in antiviral defense, RNA-mediated DNA repair, and R-loop biology [3,4,5,8].
• Studying RNA-templated transcription requires specialized methods such as RNA-seq, R-loop mapping, and in vitro transcription assays [1,2,3].
• CRISPR-based models (knockout, point mutation, knock-in, overexpression) enable functional dissection of genes involved in RNA-templated transcription [2,4].
Description
RNA-templated transcription (GO:0001172) is the biological process in which an RNA transcript is synthesized using an RNA molecule as the template. This mechanism is fundamentally different from the canonical DNA-templated transcription that produces most cellular RNAs, and it is essential for the replication of many RNA viruses and subviral agents such as viroids [1,2]. The process also occurs in cellular contexts, including RNA-mediated DNA repair and the generation of RNA-DNA hybrids known as R-loops [3,5,8]. Understanding RNA-templated transcription is therefore critical for virology, genome stability, and the development of antiviral and gene-editing tools [4,7]. Researchers study this process using model systems like potato spindle tuber viroid (PSTVd) and hepatitis delta virus (HDV), where host RNA polymerases are redirected to RNA templates [1,2,7]. Recent work has also revealed that a remodeled RNA polymerase II complex can catalyze viroid RNA-templated transcription, highlighting the interplay between host machinery and RNA templates. These findings underscore the importance of GO:0001172 in both basic RNA biology and translational research [1,2,4].
RNA-templated transcription At A Glance
| GO ID | GO:0001172 |
|---|---|
| GO term | RNA-templated transcription |
| Ontology | biological_process |
| Synonym | transcription, RNA-dependent; transcription, RNA-templated |
| Definition | The synthesis of an RNA transcript from an RNA template. |
| Major function | Synthesis of RNA from an RNA template, enabling replication of RNA viruses and viroids, and participating in RNA-mediated DNA repair. |
| Related processes | RNA-dependent RNA replication, R-loop formation, RNA-mediated DNA repair. |
| Key enzymes | Host RNA polymerases (e.g., Pol II), viral RNA-dependent RNA polymerases, and reverse transcriptases. |
| Model systems | Potato spindle tuber viroid (PSTVd), hepatitis delta virus (HDV), and E. coli RNA polymerase in vitro. |
What Is GO:0001172?
In our own words, RNA-templated transcription (GO:0001172) is the enzymatic synthesis of an RNA molecule using another RNA molecule as the template, rather than DNA. This process is also known as RNA-dependent transcription or RNA-templated transcription. It is a biological_process that encompasses the steps of template recognition, nucleotide polymerization, and transcript release, and it is carried out by specialized RNA polymerases or by host polymerases redirected to RNA templates [1,2,7].
Why Is RNA-templated transcription Important in Cell Biology?
RNA-templated transcription is important because it underpins the replication of numerous RNA viruses and viroids, many of which cause significant human, animal, and plant diseases [1,2]. It also plays a role in cellular processes such as RNA-mediated DNA repair and the regulation of genome stability through R-loops [3,5,8]. Moreover, understanding this process has led to the discovery of novel antiviral reverse transcriptases and gene synthesis mechanisms, with implications for biotechnology and medicine. Therefore, GO:0001172 is a key term for researchers in virology, RNA biology, and genome editing [1,2,4].
• Enables replication of RNA viruses and viroids, including hepatitis delta virus and potato spindle tuber viroid [1,2,7].
• Involved in RNA-mediated DNA repair, a mechanism that can maintain genome integrity [5,8].
• Contributes to R-loop biology, which is linked to transcription stress and genome instability.
• Provides a target for antiviral strategies against RNA pathogens [1,2].
• Underlies the activity of antiviral reverse transcriptases that synthesize DNA from RNA templates.
• Can be studied using bacterial RNA polymerase as a model for RNA-templated RNA extension.
• Has implications for understanding the origin and evolution of genetic information [4,8].
• Offers opportunities for CRISPR-based functional studies of host factors [2,4].
What Happens During RNA-templated transcription?
Template recognition and initiation
In simple terms: The enzyme finds the RNA template and starts making a new RNA strand.
In RNA-templated transcription, the first step is the recognition of an RNA template by an RNA polymerase or a host polymerase complex [1,2]. For viroids such as PSTVd, host RNA polymerase II is redirected to the viroid RNA genome, likely through specific RNA structures and host factors [1,2]. In hepatitis delta virus, RNA-templated transcription by pol II requires the viral antigen and specific RNA elements. Initiation involves the formation of a transcription initiation complex on the RNA template, which then catalyzes the first phosphodiester bond [1,6].
Elongation and processivity
In simple terms: The enzyme moves along the RNA template and adds nucleotides to the growing RNA chain.
During elongation, the polymerase adds ribonucleotides complementary to the RNA template, synthesizing a new RNA strand [1,6]. A remodeled RNA polymerase II complex has been shown to catalyze viroid RNA-templated transcription with high processivity. In E. coli, RNA polymerase exhibits a general RNA-templated RNA extension activity, indicating that elongation on RNA templates is not limited to viral enzymes. This step is regulated by template secondary structure and protein cofactors [1,2].
Termination and release
In simple terms: The enzyme stops and releases the newly made RNA.
Termination of RNA-templated transcription occurs when the polymerase encounters termination signals or runs out of template, leading to release of the RNA product [1,6]. For HDV, termination is influenced by the viral antigen and host factors. The released RNA can then serve as a template for further rounds of synthesis or as a functional RNA molecule [1,2].
RNA-templated DNA repair
In simple terms: RNA can also be used as a template to fix broken DNA.
Beyond RNA synthesis, RNA-templated transcription is related to RNA-templated DNA repair, where an RNA molecule serves as a template for the repair of DNA double-strand breaks [5,8]. This process involves reverse transcription of the RNA template into DNA, followed by integration or repair [5,8]. Storici et al. demonstrated that RNA can directly template DNA repair in yeast, challenging the central dogma. Meers et al. further discussed the templated versus non-templated nature of DNA repair by RNA.
R-loop formation and resolution
In simple terms: RNA can stick to DNA and form a three-stranded structure called an R-loop.
RNA-templated transcription can lead to the formation of R-loops, which are RNA-DNA hybrids that displace one DNA strand. These structures are sources of genome instability and are resolved by enzymes such as RNase H. Petermann et al. reviewed the sources, resolution, and physiological relevance of R-loops and RNA-DNA hybrids, linking them to transcription and replication stress.
Key Genes Involved in GO:0001172 RNA-templated transcription
The following genes and proteins are key players in RNA-templated transcription and its related processes, as supported by the cited literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| POLR2A | Catalytic subunit of RNA polymerase II; redirected for viroid RNA-templated transcription | Studied in PSTVd and HDV systems [1,2,7] |
| POLR2B | Second largest subunit of RNA polymerase II | Part of the remodeled Pol II complex for RNA-templated transcription |
| POLR2C | Third largest subunit of RNA polymerase II | Component of the transcription machinery |
| POLR2D | Subunit of RNA polymerase II | Involved in transcription initiation and elongation |
| POLR2E | Subunit of RNA polymerase II | Part of the core polymerase complex |
| POLR2F | Subunit of RNA polymerase II | Required for RNA-templated transcription |
| POLR2G | Subunit of RNA polymerase II | Contributes to polymerase assembly |
| POLR2H | Subunit of RNA polymerase II | Essential for catalytic activity |
| POLR2I | Subunit of RNA polymerase II | Stabilizes the polymerase complex |
| POLR2J | Subunit of RNA polymerase II | Involved in transcription regulation |
| POLR2K | Subunit of RNA polymerase II | Part of the active site region |
| POLR2L | Subunit of RNA polymerase II | Required for polymerase function |
| RNASEH1 | Resolves R-loops by degrading RNA in RNA-DNA hybrids | Linked to genome stability and RNA-templated processes |
| RNASEH2 | Removes ribonucleotides from DNA and resolves R-loops | Implicated in R-loop resolution |
| HDV antigen | Viral protein required for HDV RNA-templated transcription | Studied in HDV replication |
| E. coli RNA polymerase | Catalyzes RNA-templated RNA extension | Model for general RNA-templated transcription |
| Reverse transcriptase | Synthesizes DNA from RNA template | Antiviral defense and gene synthesis |
| PSTVd RNA | Viroid RNA template for transcription | Model for RNA-templated transcription [1,2] |
How Is RNA-templated transcription Regulated?
RNA-templated transcription is regulated at multiple levels. Host factors and RNA structures control the recruitment of RNA polymerase II to viroid RNA templates [1,2]. In HDV, the viral antigen regulates transcription initiation and elongation. R-loop formation and resolution are regulated by RNase H enzymes and other helicases, which prevent genome instability. Additionally, the activity of reverse transcriptases in antiviral defense is tightly regulated to avoid aberrant DNA synthesis. These regulatory mechanisms ensure that RNA-templated transcription occurs at the right time and place, and their dysregulation can lead to disease [1,3,4].
RNA-templated transcription and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| POLR2A | HDV infection, viroid replication | Knockout or point mutation in cell lines [2,7] |
| RNASEH1 | R-loop-associated genome instability, cancer | Knockout and overexpression models |
| RNASEH2 | Aicardi-Goutières syndrome, genome instability | Knock-in of patient mutations |
| Reverse transcriptase | Antiviral defense, gene synthesis | Overexpression in bacterial or mammalian cells |
| HDV antigen | Hepatitis delta virus infection | Knockout in HDV-infected cells |
Viral infections and viroid diseases
RNA-templated transcription is essential for the replication of hepatitis delta virus (HDV) and potato spindle tuber viroid (PSTVd), which cause liver disease in humans and severe crop losses, respectively [1,2,7]. HDV relies on host RNA polymerase II for RNA-templated transcription, making it a target for antiviral intervention. PSTVd infection in plants involves a remodeled Pol II complex, highlighting the interplay between host machinery and viroid RNA [1,2].
Genome instability and cancer
R-loops, which can arise from RNA-templated transcription, are sources of DNA damage and genome instability. Persistent R-loops are associated with cancer and neurodegenerative diseases. RNA-templated DNA repair, while generally protective, can also introduce mutations if misregulated [5,8]. Thus, dysregulation of RNA-templated processes may contribute to tumorigenesis [3,5].
Antiviral defense and biotechnology
Antiviral reverse transcriptases use RNA templates to synthesize DNA, providing a defense mechanism against RNA viruses. This process has been harnessed for de novo gene synthesis and genome editing applications. Understanding RNA-templated transcription in this context can lead to new antiviral strategies and biotechnological tools [4,6].
From RNA-templated transcription-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does POLR2A mutation affect viroid RNA-templated transcription? | Point mutation knock-in in plant or human cells |
| What is the role of RNASEH1 in resolving R-loops? | Knockout and overexpression cell lines |
| Can reverse transcriptase be used for targeted gene synthesis? | Overexpression in E. coli or mammalian cells |
| How does HDV antigen regulate RNA-templated transcription? | Knockout of HDV antigen in infected cells |
| Is E. coli RNA polymerase capable of RNA-templated RNA extension? | In vitro assays with purified enzyme |
| What host factors are required for PSTVd replication? | CRISPR knockout library screening in plant protoplasts [1,2] |
How to Study the RNA-templated transcription Process
| Method | What It Measures | Typical Application |
|---|---|---|
| In vitro transcription | RNA synthesis from RNA template | Enzyme kinetics and inhibitor testing [1,6] |
| RNA-seq | RNA transcript levels and sequences | Detecting RNA-templated products |
| DRIP-seq | R-loop formation | Mapping RNA-DNA hybrids |
| CRISPR knockout screen | Host gene requirement | Identifying factors for viroid replication |
| Mass spectrometry | Protein composition of transcription complexes | Purification of remodeled Pol II |
| Reverse transcription assay | DNA synthesis from RNA template | Antiviral reverse transcriptase activity |
| Electrophoretic mobility shift assay | RNA-protein binding | Template recognition studies [1,7] |
| Structural cryo-EM | 3D structure of polymerase-RNA complexes | Mechanistic insights |
In vitro transcription assays
In vitro transcription assays using purified RNA polymerases and RNA templates are used to measure RNA-templated transcription activity [1,6,7]. These assays allow precise control of template, nucleotides, and cofactors, and can reveal kinetic parameters and inhibitor effects [6,7].
RNA-seq and R-loop mapping
RNA sequencing (RNA-seq) can detect RNA products of RNA-templated transcription, while R-loop mapping techniques such as DRIP-seq identify RNA-DNA hybrids. These methods are used to study the genomic distribution and dynamics of RNA-templated processes.
CRISPR screening and functional genomics
CRISPR knockout and activation screens can identify host genes required for RNA-templated transcription, as demonstrated for viroid replication. Libraries targeting RNA polymerases, helicases, and RNases can reveal novel regulators [2,3].
Biochemical and structural approaches
Biochemical assays such as gel electrophoresis and mass spectrometry characterize the protein complexes involved in RNA-templated transcription [2,4]. Structural studies of RNA polymerases bound to RNA templates provide mechanistic insights.
How CRISPR Can Be Used to Study GO:0001172 RNA-templated transcription
Knockout
CRISPR knockout of host genes such as POLR2A or RNASEH1 can reveal their essential roles in RNA-templated transcription and R-loop resolution [2,3]. Knockout cell lines are valuable for studying loss-of-function phenotypes in viral replication and genome stability [2,3].
Point Mutation
Point mutations in the catalytic residues of RNA polymerase II or reverse transcriptase can dissect the enzymatic mechanism of RNA-templated transcription [2,4]. CRISPR-mediated point mutation knock-in allows precise modeling of disease-associated variants.
Knock-in
Knock-in of tagged versions of POLR2A or HDV antigen enables affinity purification and imaging of RNA-templated transcription complexes [2,7]. This approach helps identify interacting partners and dynamic localization.
Overexpression
Overexpression of reverse transcriptase or E. coli RNA polymerase can enhance RNA-templated transcription for biotechnological applications [4,6]. Overexpression models are useful for gain-of-function studies and for producing large amounts of RNA products [4,6].
How EDITGENE Supports RNA-templated transcription Research
Researchers studying RNA-templated transcription-related genes often need to determine whether a candidate gene is causally involved in the process, and CRISPR-based models provide a robust way to test this. EDITGENE offers a comprehensive suite of services to support such investigations, from knockout to overexpression and library screening.
Contact EDITGENE today to design your custom CRISPR model for RNA-templated transcription research.
Frequently Asked Questions About RNA-templated transcription
What is RNA-templated transcription?
RNA-templated transcription (GO:0001172) is the synthesis of an RNA transcript from an RNA template, as defined by the Gene Ontology.
What genes are involved in RNA-templated transcription?
Key genes include POLR2A and other RNA polymerase II subunits, RNASEH1, RNASEH2, and viral factors such as HDV antigen [2,3,7].
How is RNA-templated transcription different from DNA-templated transcription?
RNA-templated transcription uses RNA as the template, whereas DNA-templated transcription uses DNA; the former is common in RNA viruses and viroids [1,2].
What diseases are associated with RNA-templated transcription?
It is linked to hepatitis delta virus infection, viroid diseases, and genome instability through R-loops [1,2,3,7].
What model systems are used to study RNA-templated transcription?
Common models include potato spindle tuber viroid (PSTVd), hepatitis delta virus (HDV), and in vitro assays with E. coli RNA polymerase [1,2,6,7].
How can CRISPR be used to study RNA-templated transcription?
CRISPR knockout, point mutation, knock-in, and overexpression can dissect the function of host genes and viral factors involved in the process [2,4].
What methods measure RNA-templated transcription?
In vitro transcription assays, RNA-seq, DRIP-seq for R-loops, and mass spectrometry are commonly used [1,3,6].
Is RNA-templated transcription important for antiviral defense?
Yes, antiviral reverse transcriptases use RNA templates to synthesize DNA, contributing to defense against RNA viruses.
What is the role of R-loops in RNA-templated transcription?
R-loops are RNA-DNA hybrids that can form during RNA-templated transcription and are sources of genome instability if not resolved.
Can RNA-templated transcription be targeted therapeutically?
Yes, inhibiting viral RNA-templated transcription is a potential antiviral strategy, and modulating R-loop resolution may impact cancer therapy [2,3,7].
Conclusion
RNA-templated transcription (GO:0001172) is a fundamental biological process that enables RNA synthesis from RNA templates, with critical roles in viral replication, genome stability, and biotechnology [1,2,4]. Understanding its mechanisms and regulation provides insights into disease and offers opportunities for therapeutic intervention [3,7]. CRISPR-based models and advanced methods are essential tools for dissecting this process, and EDITGENE is well-positioned to support such research with its comprehensive services [2,4].
References
- 1. Dissanayaka Mudiyanselage SD et al.. 2018. Potato Spindle Tuber Viroid RNA-Templated Transcription: Factors and Regulation.. Viruses 10(9) PMID: 30227597
- 2. Dissanayaka Mudiyanselage SD et al.. 2022. A remodeled RNA polymerase II complex catalyzing viroid RNA-templated transcription.. PLoS Pathog 18(9):e1010850 PMID: 36121876
- 3. Petermann E et al.. 2022. Sources, resolution and physiological relevance of R-loops and RNA-DNA hybrids.. Nat Rev Mol Cell Biol 23(8):521-540 PMID: 35459910
- 4. Tang S et al.. 2024. De novo gene synthesis by an antiviral reverse transcriptase.. Science 386(6717):eadq0876 PMID: 39116258
- 5. Storici F et al.. 2007. RNA-templated DNA repair.. Nature 447(7142):338-41 PMID: 17429354
- 6. Galls D et al.. 2025. A general RNA-templated RNA extension activity of E. coli RNA polymerase.. RNA 31(5):663-678 PMID: 39965927
- 7. Filipovska J et al.. 2000. Specific HDV RNA-templated transcription by pol II in vitro.. RNA 6(1):41-54 PMID: 10668797
- 8. Meers C et al.. 2016. DNA repair by RNA: Templated, or not templated, that is the question.. DNA Repair (Amst) 44:17-21 PMID: 27237587
