Project description:In this data set, we compared the expression data of song nuclei HVC, visual cortex entopallium, and the molecular layer of the cerebellum dissected from females and males of 3 songbird species (S. canaria, U. cyanocephalus, P. bicolor) to identify sex-specific stimulated gene expression. Testosterone-treated male and female canaries were also included in order to study whether testosterone effect on transcriptomes is sex-specific. Finally, testosterone-treated female canaries were compared with a rare group of spontaneously singing female canaries to study whether testosterone stimulation would be different from natural stimulation.
Project description:In this data set, we compared the expression data of song nuclei HVC dissected from adult female canaries (S. canaria) implanted with 7-mm SilasticTM tubes filled with testosterone for 6 periods (1h, 3h, 8h, 3d, 7d, and 14d) with control birds (implanted with empty tube) to identify testosterone effects on gene expression.
Project description:Female European robins routinely sing during the winter season, a time when they defend feeding territories and also show elevated circulating testosterone levels. We used wild female European robins captured during fall to examine the effects of testosterone administration on the transcriptome of the song control nucleus HVC (proper name).
Project description:Background: Vocal learning is a rare and complex behavioral trait that serves as a basis for the acquisition of human spoken language. In songbirds, vocal learning and production depend on a set of specialized brain nuclei known as the song system. Methodology/Principal Findings: Using high-throughput functional genomics we have identified, 200 novel molecular markers of adult zebra finch HVC Vocal, a key node of the song system. These markers clearly differentiate HVC from the general pallial region to which HVC belongs, and thus represent molecular specializations of this song nucleus. Bioinformatics analysis reveals that several major neuronal cell functions and specific biochemical pathways are the targets of transcriptional regulation in HVC, including: 1) cell-cell and cell-substrate interactions (e.g., cadherin/catenin-mediated adherens junctions, collagen-mediated focal adhesions, and semaphorin-neuropilin/plexin axon guidance pathways); 2) cell excitability (e.g., potassium channel subfamilies, cholinergic and serotonergic receptors, neuropeptides and neuropeptide receptors); 3) signal transduction (e.g., calcium regulatory proteins, regulators of G-protein-related signaling); 4) cell proliferation/death, migration and differentiation (e.g., TGF-beta/BMP and p53 pathways); and 5) regulation of gene expression (candidate retinoid and steroid targets, modulators of chromatin/nucleolar organization). The overall direction of regulation suggest that processes related to cell stability are enhanced, whereas proliferation, growth and plasticity are largely suppressed in adult HVC, consistent with the observation that song in this songbird species is mostly stable in adulthood. Conclusions/Significance: Our study represents one of the most comprehensive molecular genetic characterizations of a brain nucleus involved in a complex learned behavior in a vertebrate. The data indicate numerous targets for pharmacological and genetic manipulations of the song system, and provide novel insights into mechanisms that might play a role in the regulation of song behavior and/or vocal learning.
Project description:Background: Vocal learning is a rare and complex behavioral trait that serves as a basis for the acquisition of human spoken language. In songbirds, vocal learning and production depend on a set of specialized brain nuclei known as the song system. Methodology/Principal Findings: Using high-throughput functional genomics we have identified, 200 novel molecular markers of adult zebra finch HVC Vocal, a key node of the song system. These markers clearly differentiate HVC from the general pallial region to which HVC belongs, and thus represent molecular specializations of this song nucleus. Bioinformatics analysis reveals that several major neuronal cell functions and specific biochemical pathways are the targets of transcriptional regulation in HVC, including: 1) cell-cell and cell-substrate interactions (e.g., cadherin/catenin-mediated adherens junctions, collagen-mediated focal adhesions, and semaphorin-neuropilin/plexin axon guidance pathways); 2) cell excitability (e.g., potassium channel subfamilies, cholinergic and serotonergic receptors, neuropeptides and neuropeptide receptors); 3) signal transduction (e.g., calcium regulatory proteins, regulators of G-protein-related signaling); 4) cell proliferation/death, migration and differentiation (e.g., TGF-beta/BMP and p53 pathways); and 5) regulation of gene expression (candidate retinoid and steroid targets, modulators of chromatin/nucleolar organization). The overall direction of regulation suggest that processes related to cell stability are enhanced, whereas proliferation, growth and plasticity are largely suppressed in adult HVC, consistent with the observation that song in this songbird species is mostly stable in adulthood. Conclusions/Significance: Our study represents one of the most comprehensive molecular genetic characterizations of a brain nucleus involved in a complex learned behavior in a vertebrate. The data indicate numerous targets for pharmacological and genetic manipulations of the song system, and provide novel insights into mechanisms that might play a role in the regulation of song behavior and/or vocal learning. Comparison of HVC and shelf regions from adult male zebra finches, 6 biological replicates per group. Each sample was hybridized against the SoNG universal reference RNA pool.
Project description:Birdsong is powerful model for the neural mechanisms underlying motor skill learning. The success of this model is in part due to the experimental advantages of the song system, the anatomically and functionally discrete neural circuit dedicated to song. Despite a detailed understanding of the physiological and systems levels properties of this circuit, we still lack a comprehensive understanding of what cell types are present in each region of the song system and how these cell types compare to those found in the brains of other vertebrates. Here, we characterize the cellular repertoire of the song motor pathway using single-cell RNA-sequencing.
Project description:Studies of transcriptional networks in multi-cellular organisms usually focus on isolated cells and typically assume that the discovered gene networks represent those present in connected cells within a complex organ like the brain. However, similar cell types connected in diverse anatomical networks could differentially influence transcriptional networks. Here, we used laser capture microdissection, expression arrays, genome mapping, and computational inference to explore behaviorally regulated gene networks in the brains of awake, behaving songbirds producing a skilled motor behavior, singing. We found that at baseline, in the absence of singing, a large proportion of genes (17%, >3000) are differentially expressed in the different brain regions of the neural circuit that controls singing. These genes predominantly code for cell communication and connectivity proteins, and non-coding RNAs. Remarkably, the act of singing was associated with differential regulation of ~10% of the coding and non-coding genome. However, less than 1% of genes were singing-regulated in most brain regions and these were largely immediate early genes (IEGs), which peaked early, including the inducible transcription factors EGR1 and FOS. The remaining vast majority of behaviorally regulated gene expression was specific to one or a subset of brain regions, which peaked later. Promoters of the baseline, common, and diverse singing regulated gene clusters were enriched for different combinations of post-translationally activated transcription factors, like CREB, SRF, MEF2, MZF, and the IEG transcription factors. The results suggest that diverse cell-to-cell interactions and differential combinatorial binding of a small group of transcription factors may influence regional diversity of gene networks in seemingly similar cell types. Thus, in highly integrated neural circuits of intact behaving animals, transcriptional network diversity appears to be the rule, rather than the exception. Gene expression in Area X, HVC, LMAN, and Ra was measured before singing (0) or after singing for 0.5, 1, 2, 3, 4, 5, 6, and 7hours. Four-Six independent experiments were performed at each of the 9 timepoints.
Project description:Photoperiod and hormonal cues drive dramatic seasonal changes in structure and function of the avian song control system. Little is known, however, about the patterns of gene expression associated with seasonal changes. Here we address this issue by exposing Gambel’s white-crowned sparrows to season-appropriate cues and extracting RNA from the telencephalic song control nuclei HVC and RA across multiple time points that capture different stages of growth and regression. We chose HVC and RA because while both nuclei change in volume across seasons, the cellular mechanisms underlying these changes differ. We thus hypothesized that different genes would be expressed between HVC and RA. We tested this by using the extracted RNA to perform a cDNA microarray hybridization developed by the SoNG initiative. We then validated these results using qRT-PCR. Supporting our hypothesis, only 59 of the 363 genes of interest were found to vary by more than |1.5| fold in expression in both nuclei, while 132 gene expression changes were HVC specific and 172 genes were RA specific. We then assigned many of these genes to functional categories relevant to the different mechanisms underlying seasonal change in HVC and RA, including neurogenesis, apoptosis, cell growth, dendrite arborization and axonal growth, angiogenesis, endocrinology, growth factors, and electrophysiology. This revealed categorical differences in the kinds of genes regulated in HVC and RA. These results show that different molecular programs underlie seasonal changes in HVC and RA, and that gene expression is time specific across different reproductive conditions. Our results provide insights into the complex molecular pathways that underlie adult neural plasticity.