Carver Biotechnology Center and High-Performance Biological Computing Group, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Proc Natl Acad Sci U S A. 2012 Oct 16;109 Suppl 2(Suppl 2):17245-52. doi: 10.1073/pnas.1200655109. Epub 2012 Oct 8.
Songbirds provide rich natural models for studying the relationships between brain anatomy, behavior, environmental signals, and gene expression. Under the Songbird Neurogenomics Initiative, investigators from 11 laboratories collected brain samples from six species of songbird under a range of experimental conditions, and 488 of these samples were analyzed systematically for gene expression by microarray. ANOVA was used to test 32 planned contrasts in the data, revealing the relative impact of different factors. The brain region from which tissue was taken had the greatest influence on gene expression profile, affecting the majority of signals measured by 18,848 cDNA spots on the microarray. Social and environmental manipulations had a highly variable impact, interpreted here as a manifestation of paradoxical "constitutive plasticity" (fewer inducible genes) during periods of enhanced behavioral responsiveness. Several specific genes were identified that may be important in the evolution of linkages between environmental signals and behavior. The data were also analyzed using weighted gene coexpression network analysis, followed by gene ontology analysis. This revealed modules of coexpressed genes that are also enriched for specific functional annotations, such as "ribosome" (expressed more highly in juvenile brain) and "dopamine metabolic process" (expressed more highly in striatal song control nucleus area X). These results underscore the complexity of influences on neural gene expression and provide a resource for studying how these influences are integrated during natural experience.
鸣禽为研究大脑解剖结构、行为、环境信号和基因表达之间的关系提供了丰富的自然模型。在鸣禽神经基因组学计划下，来自 11 个实验室的研究人员在一系列实验条件下从六种鸣禽中收集了大脑样本，其中 488 个样本通过微阵列系统地进行了基因表达分析。方差分析用于测试数据中的 32 个计划对比，揭示了不同因素的相对影响。组织采集的脑区对基因表达谱的影响最大，影响了微阵列上 18848 个 cDNA 点测量的大多数信号。社会和环境处理的影响具有高度的可变性，这里将其解释为在行为反应增强期间表现出的矛盾“组成型可塑性”（诱导基因较少）。鉴定出了一些可能在环境信号与行为之间的联系进化中很重要的特定基因。还使用加权基因共表达网络分析和基因本体分析对数据进行了分析。这揭示了共表达基因的模块，这些模块也富含特定的功能注释，例如“核糖体”（在幼年大脑中表达较高）和“多巴胺代谢过程”（在纹状体歌唱控制核区 X 中表达较高）。这些结果强调了对神经基因表达的影响的复杂性，并为研究这些影响在自然体验中是如何整合的提供了资源。
