Related Experiment Video
Updated: Nov 20, 2025
05:37
Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
1.0K
G-quadruplexes in H1N1 influenza genomes
Václav Brázda1,2, Otília Porubiaková3,4, Alessio Cantara3,5
1Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65, Brno, Czech Republic. vaclav@ibp.cz.
BMC Genomics
|January 24, 2021
Summary
Potential G-quadruplex forming sequences (PQS) were found in all 77 analyzed genotype 4 reassortant Eurasian avian-like H1N1 virus (G4-EA-H1N1) genomes. These PQS, particularly in the NP segment, represent promising targets for novel antiviral therapies against influenza.
Area of Science:
- Virology
- Genomics
- Biochemistry
Background:
- Influenza viruses are significant global health threats.
- Seventy-seven genomes of the emerging genotype 4 reassortant Eurasian avian-like H1N1 virus (G4-EA-H1N1) were analyzed.
- Potential G-quadruplex forming sequences (PQS) were investigated as possible antiviral targets.
Purpose of the Study:
- To identify and characterize PQS within G4-EA-H1N1 viral genomes.
- To assess the distribution and conservation of PQS across viral segments.
- To explore the therapeutic potential of PQS in G4-EA-H1N1 viruses.
Main Methods:
- Bioinformatic analysis of 77 G4-EA-H1N1 genomes to identify PQS.
- Sequence analysis to determine PQS frequency and distribution across viral segments.
- In vitro experimental confirmation of G-quadruplex formation using spectroscopic methods.
Main Results:
- PQS were detected in all 77 G4-EA-H1N1 genomes, totaling 571 sequences.
- The NP segment exhibited the highest PQS frequency (1.39 per 1000 nt), while the NS segment had none.
- The most conserved PQS, identified by G4Hunter score, remained stable despite extreme viral genome variation.
- G-quadruplex formation was experimentally validated in vitro.
Conclusions:
- The study identified numerous G-quadruplex forming sequences within G4-EA-H1N1 genomes.
- These PQS present viable therapeutic targets for the development of new antiviral treatments against this influenza strain.
Related Concept Videos
02:28Leaky Scanning
5.4K
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R...
5.4K
01:29Viruses with RNA Genomes
406
RNA viruses are categorized into positive-strand, negative-strand, or double-stranded groups based on their genomic structure and replication mechanisms. This classification dictates how they exploit host cellular machinery for protein synthesis and replication. Some RNA viruses also utilize reverse transcription as part of their life cycle, further diversifying their replication strategies.Positive-Strand RNA VirusesPositive-strand RNA viruses have genomes that function directly as messenger...
406
01:26Size and Structure of Viral Genomes
412
Viral genomes exhibit remarkable diversity in size, structure, and composition, influencing their replication strategies and interactions with host cells. These genomes consist of either DNA or RNA and may be linear or circular. Additionally, they can be single-stranded or double-stranded, with each configuration affecting how the virus propagates within a host. RNA viruses, for instance, generally have smaller genomes than DNA viruses, a factor that contributes to their high mutation rates and...
412
00:36Viral Mutations
37.7K
A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material...
37.7K
01:23RNA Structure
77.4K
Overview
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA): messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three RNA types consist of a...
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA): messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three RNA types consist of a...
77.4K
01:19RNA Structure
6.2K
The basic structure of RNA consists of a string of ribonucleotides attached by phosphodiester bonds. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA) involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three...
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA) involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three...
6.2K