Stepien P P, Kokot L, Leski T, Bartnik E
Department of Genetics, University of Warsaw, Poland.
Curr Genet. 1995 Feb;27(3):234-8. doi: 10.1007/BF00326154.
We have constructed a yeast mitochondrial genome containing only one group-I intron, r1, from the 21s rRNA gene and introduced this genome into a strain bearing a disruption of the suv3 gene. The presence of the r1 intron alone causes a block in respiration, while the isogenic strain containing the intronless genome is respiratory competent. Northern analysis indicates that the functional suv3 protein is necessary for the yeast cell in order to process the r1-containing transcripts: in the absence of the suv3 protein the hybridization pattern of the excised r1 intron is altered and the amount of mature 21s rRNA is 50-fold lower. We suggest that the multifunctional suv3 protein, which displays motifs of ATP-dependent RNA helicases, is necessary for the in vivo pathway leading to formation of mature 21s rRNA from the transcripts containing the r1 intron in mitochondria of Saccharomyces cerevisiae.
我们构建了一个仅包含来自21s rRNA基因的一个I类内含子r1的酵母线粒体基因组，并将该基因组导入携带suv3基因缺失的菌株中。单独存在r1内含子会导致呼吸受阻，而含有无内含子基因组的同基因菌株具有呼吸能力。Northern分析表明，功能性suv3蛋白对于酵母细胞处理含r1的转录本是必需的：在没有suv3蛋白的情况下，切除的r1内含子的杂交模式发生改变，成熟21s rRNA的量降低了50倍。我们认为，具有ATP依赖性RNA解旋酶基序的多功能suv3蛋白对于酿酒酵母线粒体中从含r1内含子的转录本形成成熟21s rRNA的体内途径是必需的。
