Coppolecchia R, Buser P, Stotz A, Linder P
Department of Microbiology, University of Basel, Switzerland.
EMBO J. 1993 Oct;12(10):4005-11. doi: 10.1002/j.1460-2075.1993.tb06078.x.
We have isolated a gene, STM1, which encodes a new translation initiation factor from Saccharomyces cerevisiae. The gene acts, if present on a multicopy plasmid, as a suppressor of a temperature-sensitive mutation in eIF-4A. The single copy STM1 gene is not essential, but disruption causes a slow growth phenotype. Analysis of polysomes from a strain carrying a disrupted stm1 allele shows a clear defect in translation initiation as shown by a strong reduction in polysomes and an increase in the monosomes. Sequence analysis revealed interesting features of the putative Stm1 protein. Comparison of the entire protein sequence with databanks showed some similarity with the human eIF-4B protein. The Stm1 protein has potential RNP1 and RNP2 motifs characteristic for RNA-binding proteins. The protein also contains six highly conserved direct repeats of 21-26 amino acids and one partial repeat.
我们分离出了一个基因STM1，它编码来自酿酒酵母的一种新的翻译起始因子。如果该基因存在于多拷贝质粒上，它可作为eIF - 4A温度敏感突变的抑制因子。单拷贝的STM1基因并非必需，但破坏该基因会导致生长缓慢的表型。对携带stm1等位基因破坏的菌株的多核糖体分析表明，翻译起始存在明显缺陷，表现为多核糖体显著减少和单核糖体增加。序列分析揭示了推定的Stm1蛋白的有趣特征。将整个蛋白质序列与数据库进行比较，发现它与人类eIF - 4B蛋白有一些相似性。Stm1蛋白具有RNA结合蛋白特有的潜在RNP1和RNP2基序。该蛋白还包含六个由21 - 26个氨基酸组成的高度保守的直接重复序列和一个部分重复序列。
