Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA.
Cereb Cortex. 2019 Mar 1;29(3):1121-1138. doi: 10.1093/cercor/bhy019.
How the variety of neurons that organize into neocortical layers and functional areas arises is a central question in the study of cortical development. While both intrinsic and extrinsic cues are known to influence this process, whether distinct neuronal progenitor groups contribute to neuron diversity and allocation is poorly understood. Using in vivo genetic fate-mapping combined with whole-cell patch clamp recording, we show that the firing pattern and apical dendritic morphology of excitatory neurons in layer 4 of the barrel cortex are specified in part by their neural precursor lineage. Further, we show that separate precursors contribute to unique features of barrel cortex topography including the intralaminar position and thalamic innervation of the neurons they generate. Importantly, many of these lineage-specified characteristics are different from those previously measured for pyramidal neurons in layers 2-3 of the frontal cortex. Collectively, our data elucidate a dynamic temporal program in neuronal precursors that fine-tunes the properties of their progeny according to the lamina of destination.
神经元如何组织成新皮层的层次和功能区域是皮质发育研究的一个核心问题。虽然已知内在和外在线索都能影响这个过程，但不同的神经元祖细胞群体是否有助于神经元的多样性和分配还知之甚少。我们使用体内遗传命运图谱结合全细胞膜片钳记录，表明在桶状皮层第 4 层中兴奋性神经元的放电模式和顶树突形态部分由其神经前体细胞系决定。此外，我们还表明，不同的前体有助于桶状皮层拓扑结构的独特特征，包括它们产生的神经元的层内位置和丘脑神经支配。重要的是，这些谱系特异性特征中的许多与之前在前额皮质 2-3 层中测量的金字塔神经元的特征不同。总的来说，我们的数据阐明了神经元前体中的一个动态时间程序，根据目标层来微调其后代的特性。
