Spatial transcriptomics mapping of basal ganglia to understand critical periods for sensorimotor learning

摘要 基底节包括产生和提炼运动序列所需的关键大脑结构 通过程序性学习获得的各种复杂行为。这些技能通常是最好的学习方法。 在早期发育关键期。先前的研究已经表明，练习这些技能会使人 基础基底节微循环内基因表达的变化。这种与行为相关的转录 青少年在感觉运动关键期观察到激活，但也发生在成人在感觉运动关键期之后 这一时期已经结束，这表明它不是专门针对学习的。值得注意的是，一个单独的转录档案是 仅在青少年中发现，并与所学技能的质量相关。这些观察结果表明， 青少年行为相关和学习相关变化的时空重叠构成了 允许学习的转录程序。为了验证这一观点，研究人员用不同类型的基底节细胞 这些程序发生了哪些，目前尚不清楚，必须得到解决。了解这些基因的转录 指纹将是破译支持感觉运动学习的分子信号通路的关键。这 该项目利用了一个特性良好的脊椎动物模型斑马雀，在该模型中，基底节转录 与实践和学习相关的变化已经通过对整个区域的整体测序得到了证明， 但尚未被追踪到不同的基底节细胞类型。因此，一个主要目标是识别和比较 行为激活和非激活基底节的单细胞基因转录本 关键时期，以确定特定的细胞类型和经历行为的细胞信号通路 受监管的变化，包括那些支持学习的变化。在这个物种中，只有雄性才会经历感觉运动 因此，与女性大脑中的类似区域进行比较，将突出最相关的变化。这个 第二个目标是选择关键的细胞类型识别符以及与感觉运动学习有关的分子 加工和开发探针以映射其在完整微电路样本中的空间表达 多重错误稳健荧光原位杂交(MerFish)。这两个综合目标将结合在一起 阐明基底节在重复的行为优化过程中如何变化，以实现最佳 感觉运动学习。这项工作对于更好地理解其背后的机制具有直接的意义。 人类行为疗法的有效性，并可能突出药物治疗目标以改进 对自闭症、中风、脑性瘫痪等脑部疾病的治疗效果。

Summary The basal ganglia comprise key brain structures for generating and refining motor sequences necessary for a variety of complex behaviors that are acquired through procedural learning. These skills are often best learned during early developmental critical periods. Prior work has shown that practicing these skills drives acute changes in gene expression within the underlying basal ganglia microcircuit. This behavior-linked transcriptional activation is observed in juveniles during the sensorimotor critical period but also occurs in adults after the critical period has closed, suggesting that it is not specific to learning. Remarkably, a separate transcriptional profile is only found in juveniles and correlates with the quality of the learned skill. These observations suggest that the spatiotemporal overlap of the behavior-linked and learning-related changes in juveniles constitute a transcriptional program that is permissive for learning. To test this idea, the individual basal ganglia cell types in which these programs occur, currently unknown, must be resolved. Understanding these ‘transcriptional fingerprints’ will be key to deciphering molecular signaling pathways that support sensorimotor learning. This project leverages a well-characterized vertebrate model, the zebra finch, in which basal ganglia transcriptional changes linked to both practice and learning have been demonstrated via bulk sequencing of the entire region, but have not yet been traced to distinct basal ganglia cell types. Thus, one major aim is to identify and compare single-cell gene transcripts from behaviorally activated and non-activated basal ganglia, during and after the critical period, in order to identify specific cell types and cell signaling pathways undergoing behaviorally regulated changes, including those that support learning. In this species, only males undergo sensorimotor learning so comparison to the analogous regions in female brains will highlight the most relevant changes. The second goal is to select key cell type identifiers as well as molecules implicated in the sensorimotor learning process and develop probes to map their spatial expression in samples of the intact microcircuit using multiplexed error-robust fluorescence in situ hybridization (MERFISH). Together, these two integrated aims will illuminate how the basal ganglia changes over the course of repeated behavioral refinement to enable optimal sensorimotor learning. This work has direct implications for better understanding of the mechanisms that underlie the effectiveness of human behavioral therapies and may highlight pharmaco-therapeutic targets to improve treatment efficacy in brain disorders ranging from autism to stroke to cerebral palsy.