Phospholipase C-related catalytically inactive protein, a novel microtubule-associated protein 1 light chain 3-binding protein, negatively regulates autophagosome formation
Phospholipase C-related catalytically inactive protein, a novel microtubule-associated protein 1 light chain 3-binding protein, negatively regulates autophagosome formation
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磷脂酶 C 相关催化失活蛋白是一种新型微管相关蛋白 1 轻链 3 结合蛋白，负调节自噬体形成
DOI：
10.1016/j.bbrc.2013.01.119
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发表时间：
2013
影响因子：
3.1
通讯作者：
H.
中科院分区：
文献类型：
--
作者：
Umebayashi;H.
在饥饿时，细胞经历自噬，即细胞内大量降解过程，以提供所需的营养。在这里，我们观察到，磷脂酶C相关的催化失活蛋白（PRIP）结合微管相关蛋白1轻链3（LC 3），哺乳动物自噬相关的启动子，调节自噬途径。然后，我们研究了PRIP在营养耗尽诱导的自噬途径中的参与。增强的PRIP与LC3的共定位在荧光显微镜下的营养饥饿的小鼠胚胎成纤维细胞中清楚地看到，和蛋白质的相互作用，揭示了免疫沉淀实验与抗LC3抗体。在饥饿条件下，有更多的绿色荧光蛋白融合LC 3点在小鼠胚胎成纤维细胞从PRIP缺陷型小鼠比在成纤维细胞从野生型细胞。通过延时显微镜评估，单个细胞中新点的形成增加。此外，PRIP缺陷细胞中自噬体形成的增加被外源性过表达的PRIP显著抑制。总之，PRIP是一种新的LC 3结合蛋白，作为自噬体形成的负调节剂。
Upon starvation, cells undergo autophagy, an intracellular bulk-degradation process, to provide the required nutrients. Here, we observed that phospholipase C-related catalytically inactive protein (PRIP) binds to microtubule-associated protein 1 light chain 3 (LC3), a mammalian autophagy-related initiator that regulates the autophagy pathway. Then, we examined the involvement of PRIP in the nutrient depletion-induced autophagy pathway. Enhanced colocalization of PRIP with LC3 was clearly seen in nutrient-starved mouse embryonic fibroblasts under a fluorescent microscope, and interaction of the proteins was revealed by immunoprecipitation experiments with an anti-LC3 antibody. Under starvation conditions, there were more green fluorescent protein fused-LC3 dots in mouse embryonic fibroblasts from PRIP-deficient mice than in fibroblasts from wild type cells. The formation of new dots in a single cell increased, as assessed by time-lapse microscopy. Furthermore, the increase in autophagosome formation in PRIP-deficient cells was notably inhibited by exogenously overexpressed PRIP. Taken together, PRIP is a novel LC3-binding protein that acts as a negative modulator of autophagosome formation.