Goodman L E, Perou C M, Fujiyama A, Tamanoi F
Department of Biochemistry and Molecular Biology, University of Chicago, IL 60637.
Yeast. 1988 Dec;4(4):271-81. doi: 10.1002/yea.320040405.
The ras proteins represent a unique example of membrane proteins which apparently do not utilize the secretory pathway for their membrane localization. Instead, it is believed that palmitic acid, covalently attached to the protein, acts as an anchor to the membranes. Recent identification of yeast mutants defective in the processing of the ras proteins has provided a novel approach for defining these biosynthetic processes. We report here the characterization of yeast DPR1, a gene essential for the processing of the ras proteins. The sequence of the gene indicates that it encodes a protein of 431 amino acids which contains no significant homology with any known proteins. It is a relatively hydrophilic protein with no apparent hydrophobic stretches. The C-terminal half of the encoded protein has an unusually high content of cysteine. The DPR1 gene product has been identified in a cell-free translation system as a protein having an apparent molecular weight of 43 kd. This represents the first step in the investigation of a novel protein-processing pathway, one that is distinct from the secretory pathway.
Ras蛋白是膜蛋白的一个独特例子，其膜定位显然不利用分泌途径。相反，据信与该蛋白共价连接的棕榈酸充当膜的锚定物。最近对Ras蛋白加工有缺陷的酵母突变体的鉴定为定义这些生物合成过程提供了一种新方法。我们在此报告酵母DPR1的特征，DPR1是Ras蛋白加工所必需的基因。该基因的序列表明它编码一个431个氨基酸的蛋白质，该蛋白质与任何已知蛋白质均无明显同源性。它是一种相对亲水的蛋白质，没有明显的疏水区域。编码蛋白质的C末端一半含有异常高含量的半胱氨酸。DPR1基因产物在无细胞翻译系统中被鉴定为一种表观分子量为43kd的蛋白质。这代表了对一种新型蛋白质加工途径进行研究的第一步，该途径不同于分泌途径。
