Tyagi Anuj, Kumar B T Naveen, Singh Niraj K
College of Fisheries, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab, 141004, India.
School of Animal Biotechnology, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab, 141004, India.
Arch Virol. 2017 Oct;162(10):3137-3142. doi: 10.1007/s00705-017-3445-7. Epub 2017 Jun 16.
We analysed the genomes and codon usage patterns of seven small (DNA and RNA) shrimp viruses. Effective number of codon (ENC) values indicated moderate (35 < ENC < 50) codon usage bias in shrimp viruses. Correlation analysis between GC compositions at non-synonymous codon and synonymous codon positions (GC1, 2 and GC3) as well as GC3 versus ENC curves indicated varying influences of mutational pressure on codon usage. The presence of deoptimized codons and host-antagonistic codon usage trends in shrimp viruses suggested the adaptation of a slow replication strategy by these viruses to avoid host defences. Low CpG frequencies indicated that shrimp viruses have evolved with underrepresentation of CpGs to avoid the host's immune response.
我们分析了七种小型（DNA和RNA）虾类病毒的基因组和密码子使用模式。有效密码子数（ENC）值表明虾类病毒存在中度（35 < ENC < 50）的密码子使用偏好。非同义密码子和同义密码子位置的GC组成（GC1、2和GC3）之间的相关性分析以及GC3与ENC曲线表明突变压力对密码子使用有不同影响。虾类病毒中存在去优化密码子和宿主拮抗密码子使用趋势，表明这些病毒采用了缓慢复制策略以避免宿主防御。低CpG频率表明虾类病毒在进化过程中CpG含量不足，以避免宿主的免疫反应。
