Project description:Similarities between speech and birdsong make songbirds advantageous for investigating the neurogenetics of learned vocal communication; a complex phenotype likely supported by ensembles of interacting genes in cortico-basal ganglia pathways of both species. To date, only FoxP2 has been identified as critical to both speech and birdsong. We performed weighted gene co-expression network analysis on microarray data from singing zebra finches to discover gene ensembles regulated during vocal behavior. We found ~2,000 singing- regulated genes comprising 3 co-expression groups unique to area X, the basal ganglia subregion dedicated to learned vocal-motor behavior. These contained known targets of human FOXP2 and potential avian targets. We validated novel biological pathways for vocalization. Our findings show that higher-order gene co-expression patterns, rather than expression levels, molecularly distinguish area X from the ventral striato-pallidum during singing. The previously unknown structure of singing-driven networks enables prioritization of molecular interactors that likely bear on human motor disorders, especially those affecting speech. Gene expression was measured in 2 basal ganglia sub-regions (area X & ventral striato-pallidum (VSP)) of 27 adult male zebra finches that sang different amounts of song over a 2hr period in the morning. 18 birds were allowed to sing freely, 9 birds were discouraged from singing by the presence of an investigator and those that sang fewer than 10 song motifs were considered “non-singers”.
Project description:Human speech is one of the few examples of vocal learning among mammals, yet ~half of avian species exhibit this ability. Its genetic basis is unknown beyond a shared requirement for FoxP2 in both humans and zebra finches. Here we manipulated FoxP2 isoforms in Area X during a critical period for song development, delineating, for the first time, unique contributions of each to vocal learning. We used weighted gene coexpression network analysis of RNA-seq data to construct transcriptional profiles and found gene modules correlated to singing, learning, or vocal variability. The juvenile song modules were preserved adults, whereas the learning modules were not. The learning modules were preserved in the striatopallidum adjacent to Area X whereas the song modules were not. The confluence of learning and singing coexpression in juvenile, but not adult, Area X may underscore molecular processes that drive vocal learning in zebra finches and, by analogy, humans.
Project description:Similarities between speech and birdsong make songbirds advantageous for investigating the neurogenetics of learned vocal communication; a complex phenotype likely supported by ensembles of interacting genes in cortico-basal ganglia pathways of both species. To date, only FoxP2 has been identified as critical to both speech and birdsong. We performed weighted gene co-expression network analysis on microarray data from singing zebra finches to discover gene ensembles regulated during vocal behavior. We found ~2,000 singing- regulated genes comprising 3 co-expression groups unique to area X, the basal ganglia subregion dedicated to learned vocal-motor behavior. These contained known targets of human FOXP2 and potential avian targets. We validated novel biological pathways for vocalization. Our findings show that higher-order gene co-expression patterns, rather than expression levels, molecularly distinguish area X from the ventral striato-pallidum during singing. The previously unknown structure of singing-driven networks enables prioritization of molecular interactors that likely bear on human motor disorders, especially those affecting speech.
