TEMPERATURE-SENSITIVE YEAST MUTANT DEFECTIVE IN RIBONUCLEIC ACID PRODUCTION
TEMPERATURE-SENSITIVE YEAST MUTANT DEFECTIVE IN RIBONUCLEIC ACID PRODUCTION
复制标题
DOI：
10.1128/jb.99.3.807-814.1969
复制
发表时间：
1969-01-01
影响因子：
3.2
通讯作者：
MCLAUGHLIN, CS
中科院分区：
文献类型：
--
作者：
HUTCHISON, HT;HARTWELL, LH;MCLAUGHLIN, CS
在酿酒酵母的突变体ts−136中，核基因的一个单一的隐性突变会引起对温度敏感的生长反应。该突变体在23℃下正常生长，但在转变到36℃后表现出对核糖核酸(RNA)积累的快速和优先抑制，表明RNA的稳定生产存在缺陷。突变株的培养从23℃转变到36℃时，表现出以下现象，表明信使RNA(MRNA)以及稳定的RNA生产存在缺陷。脉冲标记的RNA进入细胞质多核糖体甚至比净RNA积累受到更强的抑制。蛋白质合成的速度，起初不受影响，缓慢下降；这种下降与多核糖体向单核糖体的半衰期23分钟的衰退平行。突变株在36℃预孵育30分钟后保留的多聚核糖体在体内多肽合成中是活跃的，而积累的单核糖体则不活跃。此外，从36℃预培养1小时的突变体培养中分离出的核糖体在体外合成多肽方面没有活性，但可以通过添加多尿酸作为mRNA恢复到完全活性。我们的结论是，突变株−136在合成所有类型的细胞质核糖核酸或将新合成的核糖核酸从细胞核运输到细胞质的过程中存在缺陷，真核生物(酵母)的核糖核酸代谢不稳定，在36℃下的半衰期约为23min。
A single, recessive mutation in a nuclear gene confers a temperature-sensitive growth response in a mutant ofSaccharomyces cerevisiae, ts−136. The mutant grows normally at 23 C, but exhibits a rapid and preferential inhibition of ribonucleic acid (RNA) accumulation after a shift to 36 C, demonstrating a defect in stable RNA production. Cultures of the mutant which were shifted from 23 to 36 C display the following phenomena which indicate that messenger RNA (mRNA), as well as stable RNA production, is defective. The entrance of pulse-labeled RNA into cytoplasmic polyribosomes is even more strongly inhibited than is net RNA accumulation. The rate of protein synthesis, at first unaffected, decreases slowly; this decrease is paralleled by the decay of polyribosomes to monoribosomes with a half-time of 23 min. The polyribosomes which remain after a 30-min preincubation of the mutant at 36 C are active in polypeptide synthesis in vivo, whereas the monoribosomes which accumulate are not. Furthermore, ribosomes isolated from a culture of the mutant preincubated for 1 hr at 36 C are inactive in polypeptide synthesis in vitro, but can be restored to full activity by the addition of polyuridylic acid as mRNA. We conclude that mutantts−136 is defective either in the synthesis of all types of cytoplasmic RNA, or in the transport of newly synthesized RNA from the nucleus to the cytoplasm, and that the mRNA of a eucaryotic organism (yeast) is metabolically unstable, having a half-life of approximately 23 min at 36 C.