Disruption of the mouse Rce1 gene results in defective Ras processing and mislocalization of Ras within cells
Disruption of the mouse Rce1 gene results in defective Ras processing and mislocalization of Ras within cells
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DOI：
10.1074/jbc.274.13.8383
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发表时间：
1999-03-26
影响因子：
4.8
通讯作者：
Young, SG
中科院分区：
文献类型：
--
作者：
Kim, E;Ambroziak, P;Young, SG
关于哺乳动物Ras蛋白的内切蛋白水解加工所需的酶知之甚少。我们确定了一个小鼠基因（指定Rce 1），该基因与参与Ras 2 p蛋白水解加工的酵母基因（RCE 1）具有序列同源性。为了确定Rce 1在哺乳动物Ras加工中的作用，我们产生并分析了Rce 1缺陷小鼠。卷轴缺陷是致命的胚胎发育后期（胚胎后15.5天）。多条证据表明，Rce 1缺陷的胚胎和细胞缺乏内蛋白水解过程Ras蛋白的能力。首先，Ras蛋白从Rce 1缺陷细胞迁移更慢的SDS-聚丙烯酰胺凝胶比Ras蛋白从野生型胚胎和成纤维细胞。其次，Rce 1缺陷细胞的代谢标记显示Ras蛋白没有羧甲基化。最后，来自Rce 1缺陷成纤维细胞的膜缺乏蛋白水解处理法尼基化Ha-Ras、N-Ras和Ki-Ras或香叶基香叶基化Ki-Ras的能力。另外两个异戊烯化的蛋白质，法尼基化的G（γ 1）亚基的转导和geranylgeranylated Rap 1B的加工，也被阻止。内蛋白水解加工和羧甲基化的缺乏导致Ras蛋白在细胞内错误定位。这些研究表明，Reel负责哺乳动物中Ras蛋白的内切蛋白水解加工，并表明该基因在加工其他异戊二烯化CAAX蛋白中具有广泛的作用。
Little is known about the enzyme(s) required for the endoproteolytic processing of mammalian Ras proteins. We identified a mouse gene (designated Rce1) that shares sequence homology with a yeast gene (RCE1) implicated in the proteolytic processing of Ras2p. To define the role of Rce1 in mammalian Ras processing, we generated and analyzed Rce1-deficient mice. Reel deficiency was lethal late in embryonic development (after embryonic day 15.5). Multiple lines of evidence revealed that Rce1-deficient embryos and cells lacked the ability to endoproteolytically process Ras proteins. First, Ras proteins from Rce1-deficient cells migrated more slowly on SDS-polyacrylamide gels than Ras proteins from wild-type embryos and fibroblasts. Second, metabolic labeling of Rce1-deficient cells revealed that the Ras proteins were not carboxymethylated. Finally, membranes from Rce1 deficient fibroblasts lacked the capacity to proteolytically process farnesylated Ha-Ras, N-Ras, and Ki-Ras or geranylgeranylated Ki-Ras. The processing of two other prenylated proteins, the farnesylated G(gamma 1) subunit of transducin and geranylgeranylated Rap1B, was also blocked. The absence of endoproteolytic processing and carboxymethylation caused Ras proteins to be mislocalized within cells. These studies indicate that Reel is responsible for the endoproteolytic processing of the Ras proteins in mammals and suggest a broad role for this gene in processing other prenylated CAAX proteins.