A Transient Translaminar GABAergic Interneuron Circuit Connects Thalamocortical Recipient Layers in Neonatal Somatosensory Cortex.
A Transient Translaminar GABAergic Interneuron Circuit Connects Thalamocortical Recipient Layers in Neonatal Somatosensory Cortex.
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DOI：
10.1016/j.neuron.2016.01.015
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发表时间：
2016-02-03
期刊：
影响因子：
16.2
通讯作者：
Butt SJ
中科院分区：
文献类型：
--
作者：
Marques-Smith A;Lyngholm D;Kaufmann AK;Stacey JA;Hoerder-Suabedissen A;Becker EB;Wilson MC;Molnár Z;Butt SJ
GABA能活动被认为影响发育中的新皮层感觉回路。然而，出生后晚成熟的本地层（L）4电路表明替代来源的GABA能控制新生的丘脑皮质网络。我们发现，一个人口的L5 B，生长抑素（SST）阳性中间神经元接收早期丘脑突触输入，并使用激光扫描光刺激，确定这些细胞和L4棘星状（SSNs）之间的早期瞬态电路消失的L4关键期结束。感觉扰动破坏了向局部GABA能回路的过渡，表明SSN的跨椎板和局部控制之间存在联系。SST+中间神经元的条件性沉默或相反地通过过度表达神经调节蛋白-1 1 1型使回路偏向局部抑制导致突变体中缺乏早期L5 b GABA能输入和SSN的延迟丘脑神经支配。这些数据确定了L5 b SST+中间神经元在出生后早期新皮质中控制SSN的作用。出生后早期丘脑突触输入到L5 b生长抑素中间神经元L5 b IN和L4棘状星状细胞之间的瞬时相互连接感觉活动是过渡到局部L4 GABA能回路所必需的早期局部IN突触的分子偏向延迟SSN的丘脑神经支配Marques-Smith et al.鉴定一个短暂的，出生后早期GABA能中间神经元回路参与初级躯体感觉皮层的丘脑皮层整合。感觉和分子线索的扰动改变了这个回路的时间动态，从而使丘脑皮层传入输入成熟。
GABAergic activity is thought to influence developing neocortical sensory circuits. Yet the late postnatal maturation of local layer (L)4 circuits suggests alternate sources of GABAergic control in nascent thalamocortical networks. We show that a population of L5b, somatostatin (SST)-positive interneuron receives early thalamic synaptic input and, using laser-scanning photostimulation, identify an early transient circuit between these cells and L4 spiny stellates (SSNs) that disappears by the end of the L4 critical period. Sensory perturbation disrupts the transition to a local GABAergic circuit, suggesting a link between translaminar and local control of SSNs. Conditional silencing of SST+ interneurons or conversely biasing the circuit toward local inhibition by overexpression of neuregulin-1 type 1 results in an absence of early L5b GABAergic input in mutants and delayed thalamic innervation of SSNs. These data identify a role for L5b SST+ interneurons in the control of SSNs in the early postnatal neocortex. Early postnatal thalamic synaptic input onto L5b somatostatin interneurons Transient reciprocal connectivity between L5b INs and L4 spiny stellate cells Sensory activity is required for the transition to a local L4 GABAergic circuit Molecular bias toward early local IN synapses delays thalamic innervation of SSNs Marques-Smith et al. identify a transient, early postnatal GABAergic interneuron circuit involved in thalamocortical integration in primary somatosensory cortex. Perturbation of sensory and molecular cues alters the temporal dynamics of this circuit and thereby maturation of thalamocortical afferent input.