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Picornavirus Evolution: Genomes Encoding Multiple 2ANPGP Sequences-Biomedical and Biotechnological Utility.
Garry A Luke1, Lauren S Ross1, Yi-Ting Lo2
1School of Biology, University of St. Andrews, Biomolecular Sciences Research Complex, North Haugh, St. Andrews KY16 9ST, UK.
Viruses
|October 26, 2024
Summary
Picornaviruses evolved into five supergroups, with complex 2A regions in Paavivirinae. Novel 2A sequences were discovered, expanding tools for biotechnological co-expression applications.
Area of Science:
- Virology
- Molecular Biology
- Biotechnology
Background:
- Picornavirus evolution has led to five distinct supergroups, with significant variations in their 2A regions.
- The 2A region of the picornavirus polyprotein plays a crucial role and is strongly correlated with viral phylogeny.
- Supergroup 4, the Paavivirinae, exhibits complex 2A regions, often encoding multiple 2ANPGP sequences.
Purpose of the Study:
- To investigate the functional diversity of 2ANPGP sequences within the Paavivirinae.
- To identify novel 2A-like sequences with potential biotechnological applications.
- To characterize the translational properties of different 2ANPGP sequences.
Main Methods:
- In vitro transcription/translation assays were performed using synthetic polyproteins.
- Green fluorescent protein (GFP) and β-glucuronidase (GUS) were used as reporter genes linked by 2ANPGP sequences.
- Bioinformatic database searches were conducted to identify potential accessory functions.
Main Results:
- Two distinct phenotypes of 2ANPGP sequences were observed: highly active sequences and novel sequences that terminated translation.
- Some 2ANPGP sequences demonstrated high activity, comparable to foot-and-mouth disease virus 2ANPGP.
- A novel translational termination phenotype was identified for certain 2ANPGP sequences, with no detectable re-initiation of downstream GUS expression.
Conclusions:
- The identified novel 2A-like sequences significantly broaden the available tools for co-expression in biomedical and biotechnological fields.
- The diverse functionalities of 2ANPGP sequences highlight their importance in viral polyprotein processing and offer new possibilities for protein expression strategies.
- Further research into the mechanisms of these novel 2A sequences could lead to advanced protein engineering applications.
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