Body temperature and evolutionary genomics of vertebrates: a lesson from the genomes of Takifugu rubripes and Tetraodon nigroviridis.

In this paper, we provide evidence for the body temperature effect on the formation of GC-rich isochores, by analysing genomic sequences from two puffer fishes living at different temperatures. The higher body temperature of Tetraodon nigroviridis compared to Takifugu rubripes (DeltaT approximately 15 degrees C) appears to be the cause of a higher compositional heterogeneity of the former due to the formation of GC-rich regions. Such an effect does not only concern large DNA segments but also coding sequences.