Brain circuits comprise vast numbers of interconnected neurons with diverse molecular, anatomical and physiological properties. To allow targeting of individual neurons for structural and functional studies, we created light-inducible site-specific DNA recombinases based on Cre, Dre and Flp (RecVs). RecVs can induce genomic modifications by one-photon or two-photon light induction in vivo. They can produce targeted, sparse and strong labeling of individual neurons by modifying multiple loci within mouse and zebrafish genomes. In combination with other genetic strategies, they allow intersectional targeting of different neuronal classes. In the mouse cortex they enable sparse labeling and whole-brain morphological reconstructions of individual neurons. Furthermore, these enzymes allow single-cell two-photon targeted genetic modifications and can be used in combination with functional optical indicators with minimal interference. In summary, RecVs enable spatiotemporally precise optogenomic modifications that can facilitate detailed single-cell analysis of neural circuits by linking genetic identity, morphology, connectivity and function.

中文翻译：

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RecV重组酶系统，用于单细胞或细胞群体的体内靶向基因组修饰。

脑回路包括大量具有不同分子，解剖和生理特性的相互连接的神经元。为使单个神经元靶向结构和功能研究，我们基于Cre，Dre和Flp（RecVs）创建了光诱导位点特异性DNA重组酶。RecVs可以在体内通过单光子或双光子光诱导来诱导基因组修饰。通过修饰小鼠和斑马鱼基因组中的多个基因座，它们可以对单个神经元产生针对性，稀疏和强烈的标记。结合其他遗传策略，它们可以交叉靶向不同的神经元类别。在小鼠皮层中，它们使稀疏标记和单个神经元的全脑形态重建成为可能。此外，这些酶可进行单细胞双光子靶向遗传修饰，并可与功能性光学指示剂组合使用，且干扰最小。总而言之，RecV可以实现时空精确的视基因组修饰，通过链接遗传特性，形态，连通性和功能，可以促进神经回路的详细单细胞分析。