Department of Behavioral Neuroscience, Oregon Health and Sciences University, 3181 Sam Jackson Park Rd L470, Portland, OR, USA.
Current affiliation: Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA.
BMC Genomics. 2018 Apr 3;19(1):231. doi: 10.1186/s12864-018-4578-0.
The ability to imitate the vocalizations of other organisms, a trait known as vocal learning, is shared by only a few organisms, including humans, where it subserves the acquisition of speech and language, and 3 groups of birds. In songbirds, vocal learning requires the coordinated activity of a set of specialized brain nuclei referred to as the song control system. Recent efforts have revealed some of the genes that are expressed in these vocal nuclei, however a thorough characterization of the transcriptional specializations of this system is still missing. We conducted a rigorous and comprehensive analysis of microarrays, and conducted a separate analysis of 380 genes by in situ hybridizations in order to identify molecular specializations of the major nuclei of the song system of zebra finches (Taeniopygia guttata), a songbird species.
Our efforts identified more than 3300 genes that are differentially regulated in one or more vocal nuclei of adult male birds compared to the adjacent brain regions. Bioinformatics analyses provided insights into the possible involvement of these genes in molecular pathways such as cellular morphogenesis, intrinsic cellular excitability, neurotransmission and neuromodulation, axonal guidance and cela-to-cell interactions, and cell survival, which are known to strongly influence the functional properties of the song system. Moreover, an in-depth analysis of specific gene families with known involvement in regulating the development and physiological properties of neuronal circuits provides further insights into possible modulators of the song system.
Our study represents one of the most comprehensive molecular characterizations of a brain circuit that evolved to facilitate a learned behavior in a vertebrate. The data provide novel insights into possible molecular determinants of the functional properties of the song control circuitry. It also provides lists of compelling targets for pharmacological and genetic manipulations to elucidate the molecular regulation of song behavior and vocal learning.
模仿其他生物体发声的能力，即发声学习，仅存在于少数生物体中，包括人类，人类通过这种能力来获得语言和言语，以及 3 类鸟类。在鸣禽中，发声学习需要一组被称为歌唱控制系统的特定脑核的协调活动。最近的研究揭示了一些在这些发声核中表达的基因，然而，这个系统的转录特化特征仍然缺乏全面的描述。我们进行了严格和全面的微阵列分析，并通过原位杂交对 380 个基因进行了单独分析，以确定斑马雀（Taeniopygia guttata）歌唱系统主要核的分子特化。
我们的努力确定了 3300 多个基因，这些基因在成年雄性鸟类的一个或多个发声核中与相邻的脑区相比存在差异调节。生物信息学分析提供了这些基因可能参与细胞形态发生、细胞内在兴奋性、神经递质传递和神经调制、轴突导向和细胞间相互作用以及细胞存活等分子途径的见解，这些途径已知强烈影响歌唱系统的功能特性。此外，对已知参与调节神经元回路发育和生理特性的特定基因家族的深入分析，进一步深入了解歌唱系统的可能调节剂。
我们的研究代表了对脊椎动物中进化以促进习得行为的大脑回路的最全面的分子特征之一。该数据提供了对歌唱控制回路功能特性的可能分子决定因素的新见解。它还提供了有说服力的药物和遗传操作靶点的列表，以阐明歌唱行为和发声学习的分子调控。
