Developmental expression of Kcnq4 in vestibular neurons and neurosensory epithelia.
Developmental expression of Kcnq4 in vestibular neurons and neurosensory epithelia.
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Kcnq4 在前庭神经元和感觉神经上皮细胞中的发育表达。
DOI：
10.1016/j.brainres.2006.12.087
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发表时间：
2007
期刊：
影响因子：
2.9
通讯作者：
Beisel,KirkW
中科院分区：
文献类型：
--
作者：
Rocha-Sanchez,SoniaMS;Morris,KennethA;Kachar,Bechara;Nichols,David;Fritzsch,Bernd;Beisel,KirkW
内耳传入神经元和毛细胞（HCs）的感觉信号传导需要大量的离子电导。KCNQ4电压门控的m型钾通道被认为是设置耳蜗hc的静息膜电位。本研究描述了Kcnq4在前庭迷路hc中的时空表达模式和相关的可变剪接形式。采用全载免疫检测、定性和定量RT-PCR检测Kcnq4转录本和蛋白的表达模式。在发育过程中观察到Kcnq4的地形表达和上调，并表明Kcnq4不局限于特定的前庭结构或细胞类型，而是存在于传入花萼、前庭神经节神经元以及I型和II型hcc中。在四种可选择的剪接变体中，Kcnq4_v1转录本是hcc中的主要形式，而Kcnq4_v3是前庭神经元中的主要变体。Kcnq4_v1和Kcnq4_v3分别在胞囊和球囊的纹孔区和外纹孔区存在差异定量表达。沙鼠和大鼠的分析结果与小鼠相似，表明Kcnq4在前庭系统中的时空表达模式在啮齿类动物中是保守的。对缺乏任何神经支配的Bdnf条件突变小鼠前庭hc的分析表明，Kcnq4在前庭hc中的表达调节不依赖于神经支配。
Sensory signal transduction of the inner ear afferent neurons and hair cells (HCs) requires numerous ionic conductances. The KCNQ4 voltage-gated M-type potassium channel is thought to set the resting membrane potential in cochlear HCs. Here we describe the spatiotemporal expression patterns of Kcnq4 and the associated alternative splice forms in the HCs of vestibular labyrinth. Whole mount immunodetection, qualitative and quantitative RT-PCR were performed to characterize the expression patterns of Kcnq4 transcripts and proteins. A topographical expression and upregulation of Kcnq4 during development was observed and indicated that Kcnq4 is not restricted to either a specific vestibular structure or cell type, but is present in afferent calyxes, vestibular ganglion neurons, and both type I and type II HCs. Of the four alternative splice variants, Kcnq4_v1 transcripts were the predominant form in the HCs, while Kcnq4_v3 was the major variant in the vestibular neurons. Differential quantitative expression of Kcnq4_v1 and Kcnq4_v3 were respectively detected in the striolar and extra-striolar regions of the utricle and saccule. Analysis of gerbils and rats yielded results similar to those obtained in mice, suggesting that the spatiotemporal expression pattern of Kcnq4 in the vestibular system is conserved among rodents. Analyses of vestibular HCs of Bdnf conditional mutant mice, which are devoid of any innervation, demonstrate that regulation of Kcnq4 expression in vestibular HCs is independent of innervation.