Ramanathan K, Michael T H, Jiang G J, Hiel H, Fuchs P A
Center for Hearing Sciences, Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Science. 1999 Jan 8;283(5399):215-7. doi: 10.1126/science.283.5399.215.
Cochlear frequency selectivity in lower vertebrates arises in part from electrical tuning intrinsic to the sensory hair cells. The resonant frequency is determined largely by the gating kinetics of calcium-activated potassium (BK) channels encoded by the slo gene. Alternative splicing of slo from chick cochlea generated kinetically distinct BK channels. Combination with accessory beta subunits slowed the gating kinetics of alpha splice variants but preserved relative differences between them. In situ hybridization showed that the beta subunit is preferentially expressed by low-frequency (apical) hair cells in the avian cochlea. Interaction of beta with alpha splice variants could provide the kinetic range needed for electrical tuning of cochlear hair cells.
低等脊椎动物的耳蜗频率选择性部分源于感觉毛细胞固有的电调谐。共振频率在很大程度上由slo基因编码的钙激活钾（BK）通道的门控动力学决定。鸡耳蜗中slo的可变剪接产生了动力学上不同的BK通道。与辅助β亚基结合减缓了α剪接变体的门控动力学，但保留了它们之间的相对差异。原位杂交表明，β亚基在鸟类耳蜗的低频（顶端）毛细胞中优先表达。β与α剪接变体的相互作用可为耳蜗毛细胞的电调谐提供所需的动力学范围。
