Fig. 3.

Orthologous gene expression values from two species cluster by tissues, while differentially expressed genes mainly differ between tissue types for each species. a) Expression patterns of orthologous genes between upper lips of bioluminescent and nonbioluminescent ostracods are conserved. PCA clustered gene expression of 4,217 one-to-one orthologs by tissue, and differences among tissues explain >75% of the variation in the dataset. Ellipses represent 95% confidence intervals. b) Venn diagram illustrating the number of significantly upregulated genes shared across both upper lips versus compound eyes versus guts for each species, V. tsujii and Skogsbergia sp. The values in parentheses represent the percentage of shared genes found in the same orthogroup.