The membrane transport factor TAP/p115 cycles between the Golgi and earlier secretory compartments and contains distinct domains required for its localization and function.
The membrane transport factor TAP/p115 cycles between the Golgi and earlier secretory compartments and contains distinct domains required for its localization and function.
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DOI：
10.1083/jcb.143.2.319
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发表时间：
1998-10-19
期刊：
影响因子：
--
通讯作者：
Sztul E
中科院分区：
文献类型：
--
作者：
Nelson DS;Alvarez C;Gao YS;García-Mata R;Fialkowski E;Sztul E
哺乳动物蛋白 TAP/p115 及其酵母同源物 Uso1p 在膜运输中发挥重要作用。为了探究 TAP/p115 作用的位点和机制，我们的目的是对其进行本地化并确定其功能所需的域。我们发现，在间期细胞中，TAP/p115 主要定位于高尔基体和代表参与 ER 到高尔基体运输的囊泡管状簇 (VTC) 的外围结构。使用 BFA/诺考达唑治疗，我们确认 TAP/p115 存在于 ER 至高尔基体的转运中间体上。在 15°C 处理期间，TAP/p115 重新分布到含有 ERGIC-53 的外周结构，表明它是一种循环蛋白。在高尔基体中，TAP/p115 与顺式高尔基体池的顺侧和最顺式池的多形性结构相关，但在高尔基体更远端的隔室中未检测到。 TAP/p115 结合顺式高尔基体蛋白 GM130，并且 TAP/p115 的 COOH 末端酸性结构域是这种相互作用所必需的。 TAP/p115 与 GM130 的相互作用仅发生在高尔基体中，并且 TAP/p115 与外周 VTC 的关联不需要。为了检查是否需要与 GM130 相互作用才能将 TAP/p115 招募到高尔基体，缺乏酸性结构域的 TAP/p115 突变体在转染细胞中表达并定位。缺乏 GM130 结合结构域的突变体表现出正常的高尔基体定位，表明 TAP/p115 被招募到高尔基体，与其结合 GM130 的能力无关。这些突变体也能够与外周 VTC 结合。有趣的是，含有 GM130 结合结构域但缺少 NH2 末端区域部分的 TAP/p115 突变体被限制在高尔基体中并定位于 ER。 GM130 结合所需的 COOH 末端结构域和高尔基体定位所需的 NH2 末端区域似乎在功能上相关，因为缺乏这些结构域中任何一个的 TAP/p115 突变体的表达都会导致正常高尔基体形态的丧失。
The mammalian protein TAP/p115 and its yeast homologue Uso1p have an essential role in membrane traffic. To inquire into the site and mechanism of TAP/p115 action, we aimed to localize it and to identify domains required for its function. We show that in interphase cells, TAP/p115 localizes predominantly to the Golgi and to peripheral structures that represent vesicular tubular clusters (VTCs) involved in ER to Golgi transport. Using BFA/ nocodazole treatments we confirm that TAP/p115 is present on ER to Golgi transport intermediates. TAP/ p115 redistributes to peripheral structures containing ERGIC-53 during a 15°C treatment, suggesting that it is a cycling protein. Within the Golgi, TAP/p115 is associated with pleiomorphic structures on the cis side of the cis-Golgi cisterna and the cis-most cisterna, but is not detected in more distal compartments of the Golgi. TAP/p115 binds the cis-Golgi protein GM130, and the COOH-terminal acidic domain of TAP/p115 is required for this interaction. TAP/p115 interaction with GM130 occurs only in the Golgi and is not required for TAP/p115 association with peripheral VTCs. To examine whether interaction with GM130 is required to recruit TAP/p115 to the Golgi, TAP/p115 mutants lacking the acidic domain were expressed and localized in transfected cells. Mutants lacking the GM130-binding domain showed normal Golgi localization, indicating that TAP/p115 is recruited to the Golgi independently of its ability to bind GM130. Such mutants were also able to associate with peripheral VTCs. Interestingly, TAP/p115 mutants containing the GM130-binding domain but lacking portions of the NH2-terminal region were restricted from the Golgi and localized to the ER. The COOH-terminal domain required for GM130 binding and the NH2-terminal region required for Golgi localization appear functionally relevant since expression of TAP/p115 mutants lacking either of these domains leads to loss of normal Golgi morphology.
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影响因子：
64.5
作者：
Nakamura, N;Lowe, M;Warren, G
通讯作者：
Warren, G
DOI：
10.1083/jcb.131.6.1715
发表时间：
1995-12
期刊：
The Journal of cell biology
影响因子：
--
作者：
Nakamura N;Rabouille C;Watson R;Nilsson T;Hui N;Slusarewicz P;Kreis TE;Warren G
通讯作者：
Warren G
影响因子：
64.5
作者：
BALCH, WE;MCCAFFERY, JM;FARQUHAR, MG
通讯作者：
FARQUHAR, MG
影响因子：
7.5
作者：
Hay, JC;Scheller, RH
通讯作者：
Scheller, RH
影响因子：
19
作者：
Lowe, M;Nakamura, N;Warren, G
通讯作者：
Warren, G