Multiple Myo4 motors enhance ASH1 mRNA transport in Saccharomyces cerevisiae
Multiple Myo4 motors enhance ASH1 mRNA transport in Saccharomyces cerevisiae
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DOI：
10.1083/jcb.200912011
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发表时间：
2010-05-17
影响因子：
7.8
通讯作者：
Takizawa, Peter A.
中科院分区：
文献类型：
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作者：
Chung, Sunglan;Takizawa, Peter A.
在酿酒酵母中，ASH 1 mRNA通过V类肌球蛋白Myo 4转运到芽尖。在体内，Myo 4移动RNA在一个快速和连续的方式，但在体外Myo 4是一个nonprocessive，单体马达，形成一个复杂的She 3。为了了解非进行性马达如何产生连续运输，我们使用了一种新的纯化方法来证明Myo 4，She 3和RNA结合蛋白She 2是活性核糖核蛋白运输单位的唯一主要组成部分。我们证明单个定位元件包含Myo 4的多个拷贝和She 2的四聚体，这表明She 2可能为RNA募集多个马达。此外，我们表明，增加的Myo 4-She 3分子的数量结合到ASH 1 RNA在没有She 2的情况下，增加了RNA运输到芽的效率。我们的数据表明，多个，nonprocessive肌4电机可以产生连续运输的mRNA的芽尖。
In Saccharomyces cerevisiae, ASH1 mRNA is transported to the bud tip by the class V myosin Myo4. In vivo, Myo4 moves RNA in a rapid and continuous fashion, but in vitro Myo4 is a nonprocessive, monomeric motor that forms a complex with She3. To understand how nonprocessive motors generate continuous transport, we used a novel purification method to show that Myo4, She3, and the RNA-binding protein She2 are the sole major components of an active ribonucleoprotein transport unit. We demonstrate that a single localization element contains multiple copies of Myo4 and a tetramer of She2, which suggests that She2 may recruit multiple motors to an RNA. Furthermore, we show that increasing the number of Myo4-She3 molecules bound to ASH1 RNA in the absence of She2 increases the efficiency of RNA transport to the bud. Our data suggest that multiple, nonprocessive Myo4 motors can generate continuous transport of mRNA to the bud tip.