Dr. Shieh, Ru-Chi 謝如姬 博士


Dr. Shieh, Ru-Chi
謝如姬 博士

Research Fellow

  • Ph.D. University of Rochester

  • Biophysics/Electrophysics
  • Fluorescence/Ion Chennel
  • Thermodynamics


Ion channels are membrane proteins that control specific ions moving across cells. Ion movement across the cell membrane results in membrane potential changes, which are used as rapid and accurate signals in organisms. Outward currents through inward rectifier K+ channels (Kir) are important in maintaining stable resting membrane potentials, controlling excitability, and thus regulating physiological processes such as vascular tone, heart rate, renal salt flow, and insulin release.  Outward Kir currents increase as [K+]o increases and that elevated outward Kir currents are related to patho-physiological states such as in ischemia, tachycardia, and fibrillation, but the underlying mechanism remains a mystery. We have characterized how outward Kir single-channel currents and their kinetics are modulated by extracellular cations and intracellular polyamines. We are investigating how these regulations of outward Kir currents can be applicable to treatment of arrhythmia. In addition, we use Linkage Analysis based on thermodynamics to characterize and quantitate allosteric interaction of various domains in ion channels. Finally, we are developing photo-activated potassium- and calcium-selective ion channels. After both channel types are constructed, we can switch on and off cell excitability (electrical signals) via optical signals in the brain and heart, thereby allowing us to control functions and understand cell networking in these two types of cells. We anticipate the results of these studies will lead to new research tools and novel therapy interventions for a number of diseases including epilepsy in the brain as well as heart failure and arrhythmia in the heart.


離子通道是位於細胞膜上的蛋白質,負責運輸細胞內外一些特定的離子產生電流並造成細胞內外電位差。這種電位差可快速又精確地在細胞之間傳遞訊息。內向整流性的鉀通道控制細胞興奮性並進而調整許多生理功能,譬如心跳速率、腎臟鹽份的代謝及胰導素之分泌。 本實驗室結合電生理、定點突變技術及單一通道的開關分析探討內向整流性的鉀通道的基本性質如通道的開關和通道的導電性並將基礎研究得到的結果運用到生理功能及病理治療(如心律不整)的探討。此外,我們也運用熱力學的原理探討離子通道中不同區域的交互作用及其產生的能量。另一方面,我們正在研發可以被光激活的鉀離子及鈣離子通道。當我們成功地製造出此二類通道後,我們就能藉由光來調控神經及心臟細胞電訊號的開與關,進而控制這些細胞的功能以及瞭解細胞間的溝通網路。我們預期,這些研究可以發展出新的學術探討利器,並且提供一些疾病如癲癇、心臟衰竭、心律不整的治療新方法。