Ripmaster T L, Vaughn G P, Woolford J L
Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213.
Proc Natl Acad Sci U S A. 1992 Dec 1;89(23):11131-5. doi: 10.1073/pnas.89.23.11131.
We have isolated a cold-sensitive mutant of Saccharomyces cerevisiae in which there is a deficit of 60S ribosomal subunits. Cold sensitivity and the assembly defect are recessive and cosegregate, defining a single essential gene that we designated DRS1 (deficiency of ribosomal subunits). The wild-type DRS1 gene was cloned by complementation of the cold-sensitive phenotype of drs1. Sequence analysis reveals a high degree of similarity to a family of proteins that are thought to function as ATP-dependent RNA helicases. Pulse-chase analysis of ribosomal RNA synthesis and processing indicates that the drs1 mutant accumulates the 27S precursor of the mature 25S rRNA. These results suggest that, as in pre-mRNA splicing, RNA helicase activities are involved in ribosomal RNA processing.
我们分离出了酿酒酵母的一个冷敏感突变体，其中60S核糖体亚基存在缺陷。冷敏感性和组装缺陷是隐性的且共分离，定义了一个单一的必需基因，我们将其命名为DRS1（核糖体亚基缺陷）。通过互补drs1的冷敏感表型克隆了野生型DRS1基因。序列分析显示与一类被认为作为ATP依赖性RNA解旋酶发挥作用的蛋白质具有高度相似性。对核糖体RNA合成和加工的脉冲追踪分析表明，drs1突变体积累了成熟25S rRNA的27S前体。这些结果表明，如同在前体mRNA剪接中一样，RNA解旋酶活性参与核糖体RNA加工。
