McCormack T, Vega-Saenz de Miera E C, Rudy B
Department of Physiology and Biophysics, New York University Medical Center, NY 10016.
Proc Natl Acad Sci U S A. 1990 Jul;87(13):5227-31. doi: 10.1073/pnas.87.13.5227.
We report the cloning of RKShIIIA, a cDNA encoding a K+ channel sequence expressed in rat brain. This cDNA encodes K+ channel subunits that express in Xenopus oocytes a slow, 4-aminopyridine- and tetraethylammonium-sensitive, delayed rectifier-type K+ channel activated by large membrane depolarizations. This gene belongs to the Shaker (Sh) family of K+ channel genes, since the predicted protein has the same overall structure and shows significant homology to other members of this family. However, RKShIIIA cannot be assigned to either of the two known classes of Sh-family genes in mammals based on sequence analysis. Notable features of the RKShIIIA protein product include a probable cytoplasmic loop rich in prolines and a stretch very homologous to the Drosophila Shaw protein, both near the amino terminus.
我们报道了RKShIIIA的克隆，它是一个编码在大鼠脑中表达的钾离子通道序列的cDNA。该cDNA编码钾离子通道亚基，这些亚基在非洲爪蟾卵母细胞中表达一种缓慢的、对4-氨基吡啶和四乙铵敏感的、由大的膜去极化激活的延迟整流型钾离子通道。该基因属于钾离子通道基因的Shaker（Sh）家族，因为预测的蛋白质具有相同的整体结构，并且与该家族的其他成员具有显著的同源性。然而，根据序列分析，RKShIIIA不能归属于哺乳动物中已知的两类Sh家族基因中的任何一类。RKShIIIA蛋白质产物的显著特征包括靠近氨基末端的一个可能富含脯氨酸的胞质环和一段与果蝇Shaw蛋白非常同源的序列。
