Molecular characterization of rabE, a developmentally regulated Dictyostelium homolog of mammalian rab GTPases.
Molecular characterization of rabE, a developmentally regulated Dictyostelium homolog of mammalian rab GTPases.
复制标题
rabE 的分子特征，rabE 是哺乳动物 rab GTP 酶的发育调节盘基网柄菌同源物。
DOI：
10.1089/104454999315628
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
O'Halloran,T
中科院分区：
文献类型：
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作者：
Norian,L;Dragoi,IA;O'Halloran,T
小gtpase超家族包括一个亚组，兔蛋白，被认为在调节膜运输的离散步骤中起作用。采用聚合酶链反应筛选方法，从土壤黏菌阿米巴（dictyostelum）中鉴定出6个新的兔基因部分序列。这些基因的保守序列片段清楚地表明它们是拉布gtpase；独特的序列显示这些是新的兔基因。对其中一个基因的全长克隆进行了详细的鉴定，我们将其命名为rabE。rabE编码序列长度为1.1 kb，包含3个内含子。RNAse保护分析显示rabE的表达受发育调控，在发育8 h后开始信息表达。rabE氨基酸序列与数据库的比较表明，其独特结构域与4种哺乳动物rabE基因的产物最为相似。有趣的是，只有rabE蛋白及其四种哺乳动物同源物含有WDIAGQE序列，这是一个保守的GTPase结构域的变异。因此，WDIAGQE基序定义了兔蛋白的一个亚群。鉴定这组蛋白的盘基骨菌同源物为探索这组含wdiagq的兔蛋白的结构和功能打开了一个实验系统。
The superfamily of small GTPases includes a subgroup, rab proteins, thought to function in the regulation of discrete steps of membrane traffic. Using a screen based on the polymerase chain reaction, we identified six partial gene sequences of novel rab genes from the soil slime mold amoeba, Dictyostelium. Stretches of conserved sequence for these genes identified them clearly as rab GTPases; unique sequences showed these were novel rab genes. A full-length clone for one gene, which we named rabE , was characterized in detail. The coding sequence of rabE was 1.1 kb in length and contained three introns. RNAse protection analysis revealed rabE expression to be under developmental regulation, with an onset of message expression after 8 h of development. Comparison of the rabE amino acid sequence with the database showed that its unique domains were most similar to the products of four mammalian rab genes. Interestingly, only the rabE protein and its four mammalian homologs contained the sequence WDIAGQE, a variation of a conserved GTPase domain. The WDIAGQE motif thus defines a subgroup of rab proteins. Identification of a Dictyostelium homolog of this group of proteins opens an experimental system to explore the structure and function of this group of WDIAGQE-containing rab proteins.