GOLAC: an endogenous anion channel of the Golgi complex.
GOLAC: an endogenous anion channel of the Golgi complex.
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DOI：
10.1016/s0006-3495(00)76832-9
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发表时间：
2000-06
影响因子：
3.4
通讯作者：
M. H. Nordeen;S. Jones;K. Howell;J. Caldwell
中科院分区：
文献类型：
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作者：
M. H. Nordeen;S. Jones;K. Howell;J. Caldwell
高尔基复合体存在于每个真核细胞中，并在翻译后修饰和蛋白质和脂质分选到高尔基体后目的地中发挥作用。这两种功能都需要一个酸性的内腔pH值和运输的底物和副产品的高尔基体腔。预计内源性离子通道对这些功能很重要，但尚未描述。离子通道从丰富的高尔基体部分清除转运蛋白被纳入平面脂质双层。80%的单通道记录显示相同的阴离子通道。该通道具有新颖的性质，并已被命名为GOLAC（高尔基体阴离子通道）。该通道具有六个亚电导状态，最大电导为130 pS，开放时间超过95%，并且不是电压门控的。对于高尔基体功能重要的是，通道电导通过降低内腔表面上的pH而增加。这个通道可能有两个非排他性的功能：为H+-ATP酶对高尔基体腔的酸化提供抗衡离子，以及去除高尔基体中蛋白质和脂质糖基化和硫酸化产生的无机磷酸盐。
The Golgi complex is present in every eukaryotic cell and functions in posttranslational modifications and sorting of proteins and lipids to post-Golgi destinations. Both functions require an acidic lumenal pH and transport of substrates into and by-products out of the Golgi lumen. Endogenous ion channels are expected to be important for these features, but none has been described. Ion channels from an enriched Golgi fraction cleared of transiting proteins were incorporated into planar lipid bilayers. Eighty percent of the single-channel recordings revealed the same anion channel. This channel has novel properties and has been named GOLAC (Golgi anion channel). The channel has six subconductance states with a maximum conductance of 130pS, is open over 95% of the time, and is not voltage-gated. Significant for Golgi function, the channel conductance is increased by reduction of pH on the lumenal surface. This channel may serve two nonexclusive functions: providing counterions for the acidification of the Golgi lumen by the H+-ATPase and removal of inorganic phosphate generated by glycosylation and sulfation of proteins and lipids in the Golgi.