Mottes J R, Iverson L E
Division of Neurosciences Beckman Research Institute of the City of Hope, Duarte, California 91010.
Neuron. 1995 Mar;14(3):613-23. doi: 10.1016/0896-6273(95)90318-6.
Alternative splicing of the Shaker (Sh) locus of Drosophila generates several transcripts with divergent 5' and 3' domains that produce kinetically distinct K+ currents in Xenopus oocytes. Although suggestive that alternative splicing may be involved in generating K+ channel diversity, clear tissue-specific differences in the distribution of particular Sh gene products have not been demonstrated. Using lacZ as a reporter gene for accurate splicing of variable Sh3' domains, we observe differences in beta-galactosidase expression patterns in transgenic animals that indicate both temporal and spatial regulation of 3' splice choice. The differences in 3'splice choice can account for variation in recovery kinetics of Sh-encoded K+ currents recorded in adult flies. The results indicate that tissue-specific expression of functionally distinct Sh K+ channels is regulated, in part, at the level of pre-mRNA splicing and implicate sequences in or around the 3' splice sites in regulating the choice of 3' domain.
果蝇“震颤者”（Sh）基因座的可变剪接产生了几种转录本，其5'和3'结构域不同，在非洲爪蟾卵母细胞中产生动力学特性不同的K+电流。尽管提示可变剪接可能参与产生K+通道多样性，但尚未证实特定Sh基因产物分布存在明显的组织特异性差异。利用lacZ作为报告基因来精确剪接可变的Sh 3'结构域，我们在转基因动物中观察到β-半乳糖苷酶表达模式的差异，这表明3'剪接选择存在时间和空间调控。3'剪接选择的差异可以解释成年果蝇中记录到的Sh编码K+电流恢复动力学的变化。结果表明，功能不同的Sh K+通道的组织特异性表达部分在mRNA前体剪接水平受到调控，并且3'剪接位点内或其周围的序列在调控3'结构域的选择中起作用。
