Abstract：
Cortical wiring relies on guidepost cells and activity-dependent processes that are thought to act sequentially. Here, we show that the construction of layer 1 (L1), a main site of top-down integration, is regulated by crosstalk between transient Cajal-Retzius cells (CRc) and spontaneous activity of the thalamus, a main driver of bottom-up information. While activity was known to regulate CRc migration and elimination, we found that prenatal spontaneous thalamic activity and NMDA receptors selectively control CRc early density, without affecting their demise. CRc density, in turn, regulates the distribution of upper layer interneurons and excitatory synapses, thereby drastically impairing the apical dendrite activity of output pyramidal neurons. In contrast, postnatal sensory-evoked activity had a limited impact on L1 and selectively perturbed basal dendrites synaptogenesis. Collectively, our study highlights a remarkable interplay between thalamic activity and CRc in L1 functional wiring, with major implications for our understanding of cortical development.
摘要：
皮质布线依赖于路标细胞和活动依赖性过程，这些过程被认为是顺序起作用的。这里,我们证明了第1层(L1)的结构，自上而下整合的主要网站，受瞬时Cajal-Retzius细胞（CRc）和丘脑自发活动之间的串扰调节，自下而上信息的主要驱动因素。虽然已知活性可以调节CRc的迁移和消除，我们发现产前自发丘脑活动和NMDA受体选择性地控制CRc早期密度，而不会影响他们的死亡。CRc密度,反过来,调节上层中间神经元和兴奋性突触的分布，从而严重损害输出锥体神经元的顶端树突活动。相比之下,出生后的感觉诱发活动对L1的影响有限，并且选择性地干扰了基底树突的突触发生。总的来说，我们的研究强调了L1功能布线中丘脑活性与CRc之间的显着相互作用，对我们对皮质发育的理解有重要意义。
