de Castro María Pilar, Aránega Amelia, Franco Diego
Cardiovascular Development Group, Department of Experimental Biology, University of Jaén, Jaén, Spain.
Anat Rec A Discov Mol Cell Evol Biol. 2006 Mar;288(3):304-15. doi: 10.1002/ar.a.20312.
Voltage-dependent potassium channels consist of a pore-forming alpha-subunit, which is modulated by additional beta-ancillary or regulatory subunits. Kcnq1 and Kcnh2 alpha-channel subunits play pivotal roles in the developing and adult heart. However, Kcnq1 and Kcnh2 have a much wider expression profile than strictly confined to the myocardium, similar to their putative regulatory Kcne1-5 beta-subunits. At present, the distribution of distinct potassium channel subunits has been partially mapped in adult tissues, whereas almost no information is available during embryonic development. In this study, we report a detailed analysis of Kcnq1, Kcnh2, and Kcne3 protein expression during mouse embryogenesis. Our results demonstrate that Kcnq1 and Kcnh2 are widely distributed. Coexpression of both alpha-subunits is observed in a wide variety of organs, such as heart and the skeletal muscle, whereas others display unique Kcnq1 or Knch2 expression. Interestingly, Kcne3 expression is also widely observed in distinct tissue layers during embryogenesis, supporting the notion that an exquisite balance of alpha- and beta-subunit expression is required for modulating potassium conductance in distinct organs and tissue layers.
电压依赖性钾通道由一个形成孔道的α亚基组成，该亚基受其他β辅助或调节亚基的调控。Kcnq1和Kcnh2α通道亚基在发育中的心脏和成年心脏中发挥着关键作用。然而，Kcnq1和Kcnh2的表达谱比严格局限于心肌的范围要广泛得多，与其假定的调节性Kcne1-5β亚基类似。目前，不同钾通道亚基在成体组织中的分布已部分绘制出来，而在胚胎发育过程中几乎没有相关信息。在本研究中，我们报告了小鼠胚胎发育过程中Kcnq1、Kcnh2和Kcne3蛋白表达的详细分析。我们的结果表明，Kcnq1和Kcnh2分布广泛。在多种器官中观察到这两种α亚基的共表达，如心脏和骨骼肌，而其他器官则表现出独特的Kcnq1或Knch2表达。有趣的是，在胚胎发育过程中，Kcne3的表达也在不同组织层中广泛观察到，这支持了这样一种观点，即调节不同器官和组织层中的钾电导需要α亚基和β亚基表达的精确平衡。
