Aluminum fluoride stimulates surface protrusions in cells overexpressing the ARF6 GTPase.
Aluminum fluoride stimulates surface protrusions in cells overexpressing the ARF6 GTPase.
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DOI：
10.1083/jcb.134.4.935
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发表时间：
1996-08
期刊：
影响因子：
--
通讯作者：
Donaldson JG
中科院分区：
文献类型：
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作者：
Radhakrishna H;Klausner RD;Donaldson JG
为了研究ADP-核糖基化因子（ARF） 6 gtp结合蛋白的效应功能，我们用野生型、表位标记的ARF6转染HeLa细胞。先前的研究表明，氟化铝（AIF）可以间接激活ARF1 GTPase，对ARF6转染的细胞进行处理，导致ARF6和肌动蛋白重新分布到质膜上的离散位点，随着时间的推移，这些位点越来越突出。AIF的作用是可逆的，对转染野生型ARF6的细胞具有特异性，并且与表达GTPase缺陷突变型ARF6的细胞中观察到的细胞突起相似。重要的是，在转染ARF6的细胞中观察到的突起不同于分别转染RhoA和Rac1的细胞中观察到的应力纤维增强和膜褶。在形成突起的细胞中，突起结构内的巨噬细胞和膜循环明显受到刺激。相反，在这些细胞中没有检测到转铁蛋白摄取阻滞或网格蛋白AP-2复合物分布的改变。细胞松弛素D和脂氧合酶途径抑制剂阻断了aif诱导的、依赖ARF6的突起结构的形成。这些观察结果支持了ARF6 GTPase在模拟质膜和潜在细胞骨架中的新作用。
To study the effector function of the ADP- ribosylation factor (ARF) 6 GTP-binding protein, we transfected HeLa cells with wild-type, epitope- tagged ARF6. Previously shown to indirectly activate the ARF1 GTPase, aluminum fluoride (AIF) treatment of ARF6-transfected cells resulted in a redistribution of both ARF6 and actin to discrete sites on the plasma membrane, which became increasingly protrusive over time. The effects of AIF were reversible, specific to cells transfected with wild-type ARF6, and resembled the cellular protrusions observed in cells expressing the GTPase defective mutant of ARF6. Importantly, the protrusions observed in cells transfected with ARF6 were distinct from the enhanced stress fibers and membrane ruffles observed in cells transfected with RhoA and Rac1, respectively. In cells forming protrusions, there was an apparent stimulation of macropinocytosis and membrane recycling within the protrusive structures. In contrast, no block in transferrin uptake or alteration of the distribution of clathrin AP-2 complexes was detected in these cells. The AIF-induced, ARF6- dependent formation of protrusive structures was blocked by cytochalasin D and inhibitors of the lipoxygenase pathway. These observations support a novel role for the ARF6 GTPase in modeling the plasma membrane and underlying cytoskeleton.