A TRP homolog in Saccharomyces cerevisiae forms an intracellular Ca2+-permeable channel in the yeast vacuolar membrane
A TRP homolog in Saccharomyces cerevisiae forms an intracellular Ca2+-permeable channel in the yeast vacuolar membrane
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DOI：
10.1073/pnas.141036198
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发表时间：
2001-07-03
影响因子：
11.1
通讯作者：
Saimi, Y
中科院分区：
文献类型：
--
作者：
Palmer, CP;Zhou, XL;Saimi, Y
与质膜离子通道的研究相比，内膜离子通道的分子鉴定进展甚微。我们研究了酿酒酵母中 320 pS 的电压依赖性、阳离子选择性和钙激活的液泡离子电导（酵母液泡电导，YVC1）。在这里，我们报告了一个基因，其推导产物与瞬时受体电位（TRP）家族的离子通道具有显着的同源性。通过将基因删除和重新表达与酵母液泡膜直接膜片钳相结合，我们表明这种酵母TRP样基因对于YVC1电导是必需的。在生理条件下，数十微摩尔的细胞质Ca2+激活由包括Ca2+在内的阳离子穿过液泡膜携带的YVC1电流。标记的 YVC1 基因产物的免疫检测表明 YVC1 主要定位于液泡而不是其他细胞内膜。因此，我们鉴定了 YVC1 液泡/溶酶体阳离子通道基因。该报告对其他生物体中 TRP 通道的功能以及其他真核生物中液泡/溶酶体离子通道的可能分子鉴定具有影响。
The molecular identification of ion channels in internal membranes has made scant progress compared with the study of plasma membrane ion channels. We investigated a prominent voltage-dependent, cation-selective, and calcium-activated vacuolar ion conductance of 320 pS (yeast vacuolar conductance, YVC1) in Saccharomyces cerevisiae, Here we report on a gene, the deduced product of which possesses significant homology to the ion channel of the transient receptor potential (TRP) family. By using a combination of gene deletion and re-expression with direct patch clamping of the yeast vacuolar membrane, we show that this yeast TRP-like gene is necessary for the YVC1 conductance, In physiological conditions, tens of micromolar cytoplasmic Ca2+ activates the YVC1 current carried by cations including Ca2+ across the vacuolar membrane. Immunodetection of a tagged YVC1 gene product indicates that YVC1 is primarily localized in the vacuole and not other intracellular membranes. Thus we have identified the YVC1 vacuolar/lysosomal cation-channel gene. This report has implications for the function of TRP channels in other organisms and the possible molecular identification of vacuolar/lysosomal ion channels in other eukaryotes.