Phosphorylation of the vesicle-tethering protein p115 by a casein kinase II-like enzyme is required for Golgi reassembly from isolated mitotic fragments.
Phosphorylation of the vesicle-tethering protein p115 by a casein kinase II-like enzyme is required for Golgi reassembly from isolated mitotic fragments.
复制标题
酪蛋白激酶II样酶对囊泡螺旋蛋白P115的磷酸化是从分离的有丝分裂片段中重新组装的。
DOI：
10.1083/jcb.150.3.475
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发表时间：
2000-08-07
影响因子：
7.8
通讯作者：
Warren, G
中科院分区：
文献类型：
--
作者：
Dirac-Svejstrup, A B;Shorter, J;Waters, M G;Warren, G
外壳蛋白I（COPI）转运囊泡可以通过包含p115、Giantin和GM 130的纤维状卷曲螺旋蛋白的复合物拴系到高尔基体膜。p115被认为是连接囊泡上Giantin和高尔基体膜上GM 130的桥梁。在这里，我们表明，p115的酸性COOH末端介导的GM 130和Giantin的结合，以及将两者连接在一起。丝氨酸941在这个酸性结构域内的磷酸化增强了它们之间的结合以及连接。磷酸化由酪蛋白激酶II（CKII）或CKII样激酶介导。令人惊讶的是，p115的高度保守的NH 2-末端头部结构域是不需要的NSF（N-乙基马来酰亚胺敏感的融合蛋白）催化的重组cisterectin从有丝分裂的高尔基体片段在无细胞系统。然而，p115将GM 130连接到Giantin的能力以及p115在丝氨酸941处的磷酸化是NSF催化的脑池再生长所必需的。p115磷酸化可能是从COPI囊泡拴系到COPI囊泡对接的转变所必需的，这一事件涉及t-SNARE（反式可溶性NSF附着蛋白[SNAP]受体）复合物的形成。
Coat protein I (COPI) transport vesicles can be tethered to Golgi membranes by a complex of fibrous, coiled-coil proteins comprising p115, Giantin and GM130. p115 has been postulated to act as a bridge, linking Giantin on the vesicle to GM130 on the Golgi membrane. Here we show that the acidic COOH terminus of p115 mediates binding to both GM130 and Giantin as well as linking the two together. Phosphorylation of serine 941 within this acidic domain enhances the binding as well as the link between them. Phosphorylation is mediated by casein kinase II (CKII) or a CKII-like kinase. Surprisingly, the highly conserved NH2-terminal head domain of p115 is not required for the NSF (N-ethylmaleimide–sensitive fusion protein)–catalyzed reassembly of cisternae from mitotic Golgi fragments in a cell-free system. However, the ability of p115 to link GM130 to Giantin and the phosphorylation of p115 at serine 941 are required for NSF-catalyzed cisternal regrowth. p115 phosphorylation may be required for the transition from COPI vesicle tethering to COPI vesicle docking, an event that involves the formation of t-SNARE (trans–soluble NSF attachment protein [SNAP] receptor) complexes.