Mapping codon usage in sequence regions flanking cleavage positions in the hepatitis A virus polyprotein

Area of Science:

• Virology
• Molecular Biology
• Genomics

Background:

• Hepatitis A virus (HAV) is a significant human pathogen.
• Understanding viral genomic adaptations is crucial for comprehending host-pathogen interactions.
• Codon usage bias influences viral replication and protein synthesis.

Purpose of the Study:

• To investigate synonymous codon usage patterns in sequence regions flanking cleavage sites of the hepatitis A virus (HAV) polyprotein.
• To compare codon usage between HAV and its human host.
• To identify potential roles of specific codons in viral translation regulation.

Main Methods:

• Analysis of synonymous codon usage bias at codon positions in 30 HAV strains.
• Estimation of relative synonymous codon usage (RSCU) values.
• Comparative analysis of HAV genomic sequences and human host sequences.

Main Results:

• HAV demonstrates a mixed strategy of coincidence and antagonism in synonymous codon usage compared to humans.
• Specific codon positions within flanking regions show strong usage bias.
• Underrepresented codons (CUA, ACG, GUA, UCG) are preferentially used at these biased positions.

Conclusions:

• HAV's codon usage strategy may optimize its interaction with the human host's translational machinery.
• Preferential use of underrepresented codons likely regulates protein translation rates.
• These codon usage patterns may influence the secondary structure of regions near cleavage sites, impacting viral processing.