Dissociation of clathrin coats coupled to the hydrolysis of ATP: role of an uncoating ATPase.
Dissociation of clathrin coats coupled to the hydrolysis of ATP: role of an uncoating ATPase.
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DOI：
10.1083/jcb.99.2.734
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发表时间：
1984-08
期刊：
影响因子：
--
通讯作者：
Rothman JE
中科院分区：
文献类型：
--
作者：
Braell WA;Schlossman DM;Schmid SL;Rothman JE
ATP水解用于驱动网格蛋白从包被囊泡的酶促释放。发现基于其ATP依赖性分解网格蛋白笼的能力纯化的70，000-mol-wt蛋白具有网格蛋白依赖性ATP酶活性。水解对ATP是特异性的;在网格蛋白笼的存在下，dATP和其他三磷酸核糖核苷酸都不会取代ATP或抑制ATP的水解。ATP酶活性由组装笼形式的网格蛋白引起，而不是由笼解体的产物网格蛋白三聚体引起。70，000-mol-wt多肽，而不是网格蛋白，在光化学交联中被ATP标记，表明ATP的水解位点位于未包被蛋白上。低pH或高镁浓度的条件将ATP水解与网格蛋白释放解偶联，因为ATP被水解，但基本上不释放网格蛋白。这表明触发网格蛋白依赖性ATP水解的识别事件在不存在网格蛋白释放的情况下发生，并且推测在这种释放之前。
ATP hydrolysis was used to power the enzymatic release of clathrin from coated vesicles. The 70,000-mol-wt protein, purified on the basis of its ATP-dependent ability to disassemble clathrin cages, was found to possess a clathrin-dependent ATPase activity. Hydrolysis was specific for ATP; neither dATP nor other ribonucleotide triphosphates would either substitute for ATP or inhibit the hydrolysis of ATP in the presence of clathrin cages. The ATPase activity is elicited by clathrin in the form of assembled cages, but not by clathrin trimers, the product of cage disassembly. The 70,000-mol-wt polypeptide, but not clathrin, was labeled by ATP in photochemical cross-linking, indicating that the hydrolytic site for ATP resides on the uncoating protein. Conditions of low pH or high magnesium concentration uncouple ATP hydrolysis from clathrin release, as ATP is hydrolyzed although essentially no clathrin is released. This suggests that the recognition event triggering clathrin-dependent ATP hydrolysis occurs in the absence of clathrin release, and presumably precedes such release.