Expression of the potassium-chloride co-transporter, KCC2, within the avian song system.
Expression of the potassium-chloride co-transporter, KCC2, within the avian song system.
复制标题
氯化钾协同转运蛋白 KCC2 在鸟类鸣叫系统中的表达。
DOI：
10.1002/cne.24372
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Perkel,DavidJ
中科院分区：
文献类型：
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作者：
Vaaga,ChristopherE;Miller,KimberlyE;Bodor,ÁgnesL;Perkel,DavidJ
鸣禽在生命早期就通过聆听并模仿同种雄性的歌曲来学习发声。前脑通路与基底神经节-前脑回路同源，对于歌曲学习至关重要。由于非常负的氯离子逆转电位，纹状体苍白球结构、X 区和丘脑背外侧核 (DLM) 内侧部分之间的投影在成人中强烈超极化 (Person & Perkel, Neuron 46:129–140, 2005)。氯化物逆转电位部分取决于神经元特异性氯化钾协同转运蛋白 KCC2 的表达水平，KCC2 在哺乳动物中发育上调。为了确定发育过程中 X 区到 DLM 突触是否出现类似的 KCC2 表达上调，我们检测了成年斑胸草雀整个鸣叫系统以及 X 区 - DLM 突触发育过程中 KCC2 的表达水平。我们证明，KCC2 在整个鸣叫系统的一部分神经元中表达，包括 HVC（用作专有名称）、弓状皮质坚固核 (RA)、前巢状皮质外侧大细胞核 (LMAN)、X 区和 DLM。 X 区的大多数苍白球样投射神经元表现出 KCC2 免疫反应性。在成人中，KCC2 表达在 DLM 中很强，并且在孵化后 14 至 24 天、开始鸣叫之前表达上调。光学和电子显微镜分析表明 KCC2 免疫反应性与质膜密切相关。因此，在哺乳动物大脑中的歌曲系统中，KCC2 的表达可以很好地调节 GABA 逆转潜力。
Songbirds learn to produce vocalizations early in life by listening to, then copying the songs of conspecific males. The anterior forebrain pathway, homologous to a basal ganglia‐forebrain circuit, is essential for song learning. The projection between the striato‐pallidal structure, Area X, and the medial portion of the dorsolateral thalamic nucleus (DLM) is strongly hyperpolarizing in adults, due to a very negative chloride reversal potential (Person & Perkel, Neuron 46:129–140, 2005). The chloride reversal potential is determined, in part, by the expression level of a neuron‐specific potassium‐chloride cotransporter, KCC2, which is developmentally upregulated in mammals. To determine whether a similar upregulation in KCC2 expression occurs at the Area X to DLM synapse during development, we examined the expression level of KCC2 in adult zebra finches across the song system as well as during development in the Area X – DLM synapse. We demonstrate that KCC2 is expressed in a subset of neurons throughout the song system, including HVC (used as a proper name), robust nucleus of the arcopallium (RA), lateral magnocellular nucleus of the anterior nidopallium (LMAN), Area X, and DLM. The majority of pallidal‐like projection neurons in Area X showed KCC2 immunoreactivity. In adults, KCC2 expression was robust within DLM, and was upregulated between 14 and 24 days post hatching, before the onset of song learning. Light and electron microscopic analysis indicated that KCC2 immunoreactivity is strongly associated with the plasma membrane. Thus, in the song system as in the mammalian brain, KCC2 expression is well placed to modulate the GABAAreversal potential.