Brow D A
Department of Biology, University of California, San Diego, La Jolla 92093.
J Biol Chem. 1987 Oct 15;262(29):13959-65.
When a yeast 5 S rRNA gene with a variant 3'-terminal nucleotide sequence was transcribed in a homologous cell-free system, primary transcripts that were shorter, more heterogeneous in length and much more resistant to processing than pre-5 S rRNA from the major "repeat" 5 S rRNA gene were produced. After 3'-end processing, variant 5 S rRNA was one nucleotide shorter than mature repeat 5 S rRNA and was bound much less strongly to ribosomal protein YL3. The stable variant pre-5 S rRNA appeared to bind another, unidentified protein. The formation of this presumptive ribonucleoprotein complex was disrupted by (Up)4UOH, suggesting that it may contain a yeast analog of the mammalian La protein.
当一个具有变异3'-末端核苷酸序列的酵母5S rRNA基因在同源无细胞系统中进行转录时，所产生的初级转录本比来自主要“重复”5S rRNA基因的前体5S rRNA更短、长度更不均一，并且对加工的抗性更强。在进行3'-末端加工后，变异型5S rRNA比成熟的重复型5S rRNA短一个核苷酸，并且与核糖体蛋白YL3的结合力弱得多。稳定的变异型前体5S rRNA似乎与另一种未鉴定的蛋白质结合。(Up)4UOH可破坏这种假定的核糖核蛋白复合物的形成，这表明它可能含有哺乳动物La蛋白的酵母类似物。
