Abstract

Increased relative brain size characterizes the evolution of primates, suggesting that enhanced cognition plays an important part in the be-havioral adaptations of this mammalian order. In addition to changes in brain anatomy, cognition can also be regulated by molecular changes that alter synaptic function, but little is known about modifi-cations of synapses in primate brain evolution. The aim of the current study was to investigate the expression patterns and evol-ution of 20 synaptic genes from the prefrontal cortex of 12 primate species. The genes investigated included glutamate receptors, scaf-folding proteins, synaptic vesicle components, as well as factors in-volved in synaptic vesicle release and structural components of the nervous system. Our analyses revealed that there have been signifi-cant changes during primate brain evolution in the components of the glutamatergic signaling pathway in terms of gene expression, protein expression, and promoter sequence changes. These results