Complementation of physiological and behavioral defects by a slowpoke Ca2+-activated K+ channel transgene
Complementation of physiological and behavioral defects by a slowpoke Ca2+-activated K+ channel transgene
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DOI：
10.1046/j.1471-4159.2000.751310.x
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发表时间：
2000-09-01
影响因子：
4.7
通讯作者：
Atkinson, NS
中科院分区：
文献类型：
--
作者：
Brenner, R;Yu, JY;Atkinson, NS
果蝇Slowpoke基因编码一种大电导钙激活钾通道，用于神经元、肌肉和一些上皮细胞。组织特异的转录启动子和选择性的mRNA剪接产生了大量的转录本，这些不同的转录本被认为是根据细胞的要求定制通道的属性。据推测，单一的剪接变体不能满足所有细胞类型的特定需求。为了测试这一点，我们检查了单个慢速剪接变体是否能够补充所有慢速行为表型，慢速剪接中的空突变导致动物半不能飞，并表现出可诱导的“粘足”表型。在转基因果蝇中，利用特征明确的SlowPke转录控制区来指导单个SlowPke剪接变异体(CDNAH13)的表达。这些果蝇的内源性基因已经被slo(4)突变失活。动作电位记录和电压钳记录显示转基因产生了功能通道，转基因完全补充了飞行缺陷，但不是粘足表型，我们得出结论，通过选择性剪接产生的不同的慢拨通道亚型是不可互换的，是不同类型细胞正常功能所必需的。
The Drosophila slowpoke gene encodes a large conductance calcium-activated potassium channel used in neurons, muscle, and some epithelial cells. Tissue-specific transcriptional promoters and alternative mRNA splicing generate a large array of transcripts, These distinct transcripts are thought to tailor the properties of the channel to the requirements of the cell. Presumably, a single splice variant cannot satisfy the specific needs of all cell types. To test this, we examined whether a single slowpoke splice variant was capable of complementing all slowpoke behavioral phenotypes, Null mutations in slowpoke cause animals to be semiflightless and to manifest an inducible "sticky-feet" phenotype. The well-characterized slowpoke transcriptional control region was used to direct the expression of a single slowpoke splice variant (cDNA H13) in transgenic flies. The endogenous gene in these flies had been inactivated by the slo(4) mutation. Action-potential recordings and voltage-clamp recordings demonstrated the production of functional channels from the transgene, The transgene completely complemented the flight defect, but not the sticky-feet phenotype, We conclude that distinct slowpoke channel isoforms, produced by alternative splicing, are not interchangeable and are required for proper function of different cell types.