Comprehensive profiling of codon usage signatures and codon context variations in the genus Ustilago

Area of Science:

• Genomics
• Molecular Biology
• Mycology

Background:

• The fungal genus Ustilago comprises significant plant pathogens.
• Genome sequencing advances enable detailed analysis of Ustilago biology.
• Understanding codon and amino acid usage patterns is crucial for pathogen research.

Purpose of the Study:

• To investigate the factors influencing codon and amino acid usage in Ustilago.
• To identify selection pressures and constraints shaping gene expression.
• To explore potential targets for combating Ustilago pathogenesis.

Main Methods:

• Multivariate statistical analysis of Ustilago genomes.
• Examination of codon usage bias and amino acid composition.
• Analysis of gene expressivity and sequence features.
• Investigation of codon context and dinucleotide frequencies.

Main Results:

• Natural selection for translational accuracy is a primary driver of codon usage.
• Gene expressivity significantly impacts codon usage variations.
• Amino acid usage is influenced by protein properties (aromatic, hydrophobic) and sequence length.
• UpA dinucleotides are avoided at codon junctions to prevent nonsense mutations and enhance translational efficiency.

Conclusions:

• Codon usage in Ustilago is shaped by a balance of selection and constraints.
• Identification of optimal codons and avoided pairs offers insights for targeted genetic manipulation.
• These findings can inform strategies to control Ustilago plant diseases at the molecular level.