Rosenblatt K P, Sun Z P, Heller S, Hudspeth A J
Howard Hughes Medical Institute and Laboratory of Sensory Neuroscience, The Rockefeller University, New York, New York 10021-6399, USA.
Neuron. 1997 Nov;19(5):1061-75. doi: 10.1016/s0896-6273(00)80397-9.
In some cochleae, the number and kinetic properties of Ca2+-activated K+ (KCa) channels partly determine the characteristic frequency of each hair cell and thus help establish a tonotopic map. In the chicken's basilar papilla, we found numerous isoforms of KCa channels generated by alternative mRNA splicing at seven sites in a single gene, cSlo. In situ polymerase chain reactions demonstrated cSlo expression in hair cells and revealed differential distributions of KCa channel isoforms along the basilar papilla. Analysis of single hair cells by the reverse transcription polymerase chain reaction confirmed the differential expression of channel variants. Heterologously expressed cSlo variants differed in their sensitivities to Ca2+ and voltage, suggesting that the distinct spatial distributions of cSlo variants help determine the tonotopic map.
在一些耳蜗中，Ca2+激活的K+（KCa）通道的数量和动力学特性部分决定了每个毛细胞的特征频率，从而有助于建立音调拓扑图。在鸡的基底乳头中，我们发现了由单个基因cSlo中七个位点的可变mRNA剪接产生的大量KCa通道亚型。原位聚合酶链反应证明cSlo在毛细胞中表达，并揭示了KCa通道亚型沿基底乳头的差异分布。通过逆转录聚合酶链反应对单个毛细胞的分析证实了通道变体的差异表达。异源表达的cSlo变体对Ca2+和电压的敏感性不同，这表明cSlo变体的不同空间分布有助于确定音调拓扑图。
