Data from: The evolution of protein-coding gene structure in eukaryotes

Introns are highly prevalent in most eukaryotic genomes. Despite the
accumulating evidence for benefits conferred by the possession of introns,
their specific roles and functions, as well as the processes shaping their
evolution, are still only partially understood. Here we explore the
evolution of the eukaryotic gene intron-exon structure by focusing on
several key features such as the intron length, the number of introns, and
the intron-to-exon ratio of protein-coding genes. We utilize whole genome
data from 590 species covering the main eukaryotic taxonomic groups and
analyze them within a statistical phylogenetic framework. We found that
the basic gene structure differs markedly among the main eukaryotic phyla,
with animals, and particularly chordates, displaying intron-rich genes,
compared to plants and fungi. Reconstruction of gene structure evolution
suggests that these differences had evolved prior to the divergence of the
phyla, and have remained mostly conserved within groups. We revisit the
previously reported association between the genome size and the mean
intron length, and report that the correlation patterns differ
considerably among phyla. Our findings suggest that the evolution of
introns may be affected by different processes across the eukaryotic tree.
The substantial diversity in gene structures may indicate that introns
play different molecular and evolutionary roles in different organisms.