Batiza A F, Schulz T, Masson P H
Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
J Biol Chem. 1996 Sep 20;271(38):23357-62. doi: 10.1074/jbc.271.38.23357.
We have used the transgenic AEQUORIN calcium reporter system to monitor the cytosolic calcium ([Ca2+]cyt) response of Saccharomyces cerevisiae to hypotonic shock. Such a shock generates an almost immediate and transient rise in [Ca2+]cyt which is eliminated by gadolinium, a blocker of stretch-activated channels. In addition, this transient rise in [Ca2+]cyt is initially insensitive to 1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA), an extracellular calcium chelator. However, BAPTA abruptly attenuates the maintenance of that transient rise. These data show that hypotonic shock generates a stretch-activated channel-dependent calcium pulse in yeast. They also suggest that the immediate calcium influx is primarily generated from intracellular stores, and that a sustained increase in [Ca2+]cyt depends upon extracellular calcium.
我们使用转基因水母发光蛋白钙报告系统来监测酿酒酵母对低渗休克的胞质钙（[Ca2+]cyt）反应。这种休克几乎立即引起[Ca2+]cyt的短暂升高，而钆（一种牵张激活通道阻滞剂）可消除这种升高。此外，[Ca2+]cyt的这种短暂升高最初对细胞外钙螯合剂1,2-双-（邻氨基苯氧基）乙烷-N,N,N',N'-四乙酸（BAPTA）不敏感。然而，BAPTA会突然减弱这种短暂升高的维持。这些数据表明，低渗休克在酵母中产生了一种牵张激活通道依赖性钙脉冲。它们还表明，即时钙内流主要来自细胞内储存，并且[Ca2+]cyt的持续增加依赖于细胞外钙。
