Li G, Wang J, Rossiter SJ, Jones G, Zhang S (2007) Accelerated FoxP2 Evolution in Echolocating Bats. PLoS ONE 2(9): e900. doi:10.1371/
journal.pone.0000900
FOXP2 a fait parler de lui il y a quelques mois, à cause de son implication probable dans le processus d’acquisition de la parole par les humains, sur une différence de deux malheureux aminoacides. Le voilà à nouveau associé avec une fonction impliquant le traitement du son, cette fois chez les sauve-souris, chez qui il semble avoir évolué plus rapidement et différentiellement chez les deux groupes qui utilisent des méthodes différentes d’écholocation, à fréquence constante ou modulée.
FOXP2 is a transcription factor implicated in the development and neural control of orofacial coordination, particularly with respect to vocalisation. Observations that orthologues show almost no variation across vertebrates yet differ by two amino acids between humans and chimpanzees have led to speculation that recent evolutionary changes might relate to the emergence of language. Echolocating bats face especially challenging sensorimotor demands, using vocal signals for orientation and often for prey capture. To determine whether mutations in the FoxP2 gene could be associated with echolocation, we sequenced FoxP2 from echolocating and non-echolocating bats as well as a range of other mammal species. We found that contrary to previous reports, FoxP2 is not highly conserved across all nonhuman mammals but is extremely diverse in echolocating bats. We detected divergent selection (a change in selective pressure) at FoxP2 between bats with contrasting sonar systems, suggesting the intriguing possibility of a role for FoxP2 in the evolution and development of echolocation. We speculate that observed accelerated evolution of FoxP2 in bats supports a previously proposed function in sensorimotor coordination.
