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FoxP2 in Learned Avian Vocalizations| old_uid | 5382 |
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| title | FoxP2 in Learned Avian Vocalizations |
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| start_date | 2008/10/14 |
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| schedule | 15h45-17h |
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| online | no |
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| summary | The FOXP2 gene is essential for developing the full articulatory power of human language and was apparently the target of positive selection during recent human evolution. Mutations of FOXP2 cause a speech and language disorder that compromises the fluent production of words and the correct use and comprehension of grammar. FOXP2 patients have structural and functional abnormalities in the striatum of the basal ganglia, where high levels of FOXP2 expression occur.
Since human speech and learned vocalizations in songbirds bear behavioral and neural parallels, songbirds provide a genuine model for investigating the basic principles of speech and its pathologies. We therefore compared FoxP2 sequences of three orders of birds capable of vocal imitations with birds lacking song learning ability but found no correlation between a particular version of the FoxP2 coding region and a species’ capacity for vocal imitation.
However, we did find correlations between FoxP2 expression levels in Area X, a basal ganglia structure necessary for song acquisition, and times of vocal plasticity, both in young zebra finches and adult canaries. We therefore downregulated FoxP2 in Area X of juvenile finches, using lentivirus-mediated RNAi to determine effects on song development. We found that FoxP2 knockdown in Area X resulted in incomplete and inaccurate tutor imitation. Inaccurate and incomplete imitation of sounds are also core deficits of orofacial dyspraxia.
Together, our findings suggest that normal auditory-guided vocal motor learning in the basal ganglia of songbirds requires FoxP2. These findings provide the first example of a functional gene analysis in songbirds, a widely studied neuroethological model system. The fact that FoxP2 is involved in both birdsong and speech implies that some of the molecular substrates for the uniquely human capacity of language are not exclusive to the hominid lineage. Ongoing studies examine the molecular targets of FoxP2 in vitro and in vivo. |
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| responsibles | Zondervan |
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