Original investigationFoxP2 expression in an echolocating bat (Rhinolophus ferrumequinum): Functional implications

Disruption of FOXP2, a gene encoding a forkhead domain transcription factor, may cause a severe developmental disorder of verbal communication, especially vocalization. In insectivorous bats, accelerated evolution of FoxP2 supports a previously proposed hypothesis that this gene plays a role in sensorimotor coordination. In order to validate this hypothesis, it is necessary to examine the expression of FoxP2 in the relevant sensorimotor structures involved in echolocation behavior. Here, we present the detailed spatial expression pattern of FoxP2 in the mature brain of Rhinolophus ferrumequinum using immunohistochemistry. FoxP2 expression was found in many regions of the bat brain. The homologous pattern of FoxP2 expression in this bat argues for the role of the gene in motor-related circuits. In addition, FoxP2 was strongly expressed in many regions related to echolocation such as the inferior colliculus, superior colliculus, periaqueductal gray, paralemniscal nucleus, nuclei of the lateral lemniscus, parabrachial nucleus and ambiguous nucleus. Overall, our findings imply that FoxP2 plays an important role in echolocation.