Bitter taste receptor genes of primates

Bitter taste perception plays a critical role in deterring animals from
consuming harmful and toxic substances. To characterize the evolution of
primate Tas2rs and test whether dietary preference has shaped the Tas2rs
repertoire of primates, we identified Tas2r genes of 35 genomes including
16 Cercopithecidae species, 6 Hominidae species, 4 Cebidae species, 3
Lemuridae species, and other 6 species. The results showed that the total
numbers of primates' Tas2rs ranged from 27 to 51, which concentrated
on 2–4 scaffolds of each species and the closely related genes tandemly
duplicated in the same scaffold. Phylogenetic construction revealed that
the Tas2r genes can be divided into 21 clades, among which,
anthropoid-specific clades, Prosimii-specific clade, clades with multiple
gene copies, or even Cercopithecidea-specific Tas2rs were detected. In
addition, phylogenetically independent contrast (PIC) analysis revealed
that the number of intact Tas2rs was significantly correlated with feeding
preferences. Altogether, our data supported diet as a driving force of
primate Tas2rs evolution, and Cercopithecidae species have developed some
specific Tas2rs during the evolutionary process. These results are
probably because most Cercopithecidae species feed on plants containing
many toxins, and it is necessary to develop specialized Tas2rs to protect
them from poisoning.