Next, for each gene with rate changes, we examined whether the changes in dN/ dS ratio can be explained by higher or lower codon usage bias in a specific lineage.
A large number of differentially spliced genes (59%) displayed differential isoform usage in a stimuli-specific manner, with 789 being differentially spliced in a single condition (Supplementary Fig. 3a).
Flaviviridae viruses mimicked host nucleotide motif usage in a host-specific manner.
Other selective pressure could modulate viral codon usage in a more segment-specific manner (e.g. conservation of RNA motif/structure for other virological processes, fine-tuning of translation kinetics) [ 21, 28].
This is consistent with bias toward the preferential usage of a specific subset of codons in more highly expressed genes.
Our final data set for analysis was a matrix in which the rows correspond to the genes of one human PV genome and the columns to the 59 codons, such that each row has the codon usage information for a specific gene, in terms of relative frequencies.
The complexity can be simplified by concentrating on wobble base modifications in specific tRNAs and then analyzing patterns of codon usage in specific transcripts, but an appreciation of the degeneracy of the genetic code is required to move the model to the next level.
This antibody has been validated for usage in conformationally specific selections in previous studies [ 13, 17, 18].
Furthermore, the server only provides classifiers for 111 Molecular function and 86 Biological Process categories that represent more general annotations, which limits its usage in deciphering specific annotations.
Plotkin et al. [ 26] showed that codon usage in tissue specific genes varies among genes expressed in different tissues, suggesting that it could be affected by differential tRNA abundances.
