Dynamics of Auxilin 1 and GAK in clathrin-mediated traffic
Dynamics of Auxilin 1 and GAK in clathrin-mediated traffic
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网格蛋白介导的交通中辅助蛋白 1 和 GAK 的动态。
DOI：
10.1083/jcb.201908142
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发表时间：
2020-03-02
影响因子：
7.8
通讯作者：
Kirchhausen, Tom
中科院分区：
文献类型：
--
作者：
He, Kangmin;Song, Eli;Kirchhausen, Tom
网格蛋白包被的囊泡通过Hsc 70-未包被的ATP酶的作用在夹断的数秒内失去其网格蛋白晶格。“J-和PTEN样结构域的蛋白质，auxilin 1（auxilin 1）和auxilin 2（GAK），招募Hsc 70。PTEN样结构域没有磷酸酶活性，但它可以识别磷脂酰肌醇磷酸头基。在发动蛋白介导的膜断裂将囊泡从质膜释放后，GAK和GAT 1立即以连续的瞬时爆发出现在包被囊泡上。这些爆发包含非常少量的生长素，甚至四到六个分子就足以介导脱壳。与此相反，我们不能检测到生长素在失败的坑或在任何时候在涂层坑组装。我们之前表明网格蛋白包被的囊泡具有动态的磷酸肌醇景观，并且我们提出脂质头基识别可能决定Aux 1和GAK出现的时间。差异招聘的RISK 1和GAK相关的时间变化的磷脂酰肌醇组成，与脂质开关定时机制一致。
Clathrin-coated vesicles lose their clathrin lattice within seconds of pinching off, through the action of the Hsc70 "uncoating ATPase." The J- and PTEN-like domain-containing proteins, auxilin 1 (Aux1) and auxilin 2 (GAK), recruit Hsc70. The PTEN-like domain has no phosphatase activity, but it can recognize phosphatidylinositol phosphate head groups. Aux1 and GAK appear on coated vesicles in successive transient bursts, immediately after dynamin-mediated membrane scission has released the vesicle from the plasma membrane. These bursts contain a very small number of auxilins, and even four to six molecules are sufficient to mediate uncoating. In contrast, we could not detect auxilins in abortive pits or at any time during coated pit assembly. We previously showed that clathrin-coated vesicles have a dynamic phosphoinositide landscape, and we have proposed that lipid head group recognition might determine the timing of Aux1 and GAK appearance. The differential recruitment of Aux1 and GAK correlates with temporal variations in phosphoinositide composition, consistent with a lipid-switch timing mechanism.