Evidence for long-lived mRNA during fruiting body formation in myxococcus xanthus.
Evidence for long-lived mRNA during fruiting body formation in myxococcus xanthus.
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黄粘球菌子实体形成过程中 mRNA 寿命较长的证据。
DOI：
10.1073/pnas.80.5.1467
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发表时间：
1983
影响因子：
11.1
通讯作者：
Zusman,DR
中科院分区：
文献类型：
--
作者：
Nelson,DR;Zusman,DR
通过用利福平抑制RNA聚合酶，然后测量[35 S]甲硫氨酸掺入蛋白质的速率来测定黄色粘球菌mRNA的半衰期。重悬于克隆子实体液体培养物中的营养细胞显示出约3.5分钟的平均mRNA半衰期。（24或48小时）表现出双相衰减曲线，表观mRNA半衰期约为3.5分钟和20-30分钟。48小时细胞的所有mRNA。通过NaDodSO 4/聚丙烯酰胺凝胶电泳分析35 S标记的蛋白质表明，利福平处理30分钟后，仅合成5-10个主要多肽。其中之一是蛋白S，孢子表面的外壳蛋白，因为免疫沉淀的35 S标记的蛋白质与特异性的蛋白S的抗血清表明，在利福平的存在下继续合成的蛋白S。其mRNA的半衰期计算为15-30分钟。从营养和发育细胞的RNA脉冲标记与32 PO 4随后利福平治疗。在3%NaDodSO_4/聚丙烯酰胺凝胶上分析标记的RNA，显示在发育中的细胞中有5-10条长寿命mRNA带。这些结果表明，有几个丰富的mRNA种类合成发育异常长寿。大多数mRNA种类显示较短半衰期的事实表明，发育中的细胞保留了mRNA降解的正常机制。
Half-lives of Myxococcus xanthus mRNA were determined by inhibiting RNA polymerase with rifampin and then measuring the rate of [35S]methionine incorporation into protein. Vegetative cells resuspended in clone fruiting liquid culture showed an average mRNA half-life of approximately 3.5 min. Developmental cells (24 or 48 hr) exhibited biphasic decay curves with apparent mRNA half-lives of approximately 3.5 min and 20-30 min. The more-stable mRNA species accounted for about 30% of all mRNA present in 24-hr cells and as much as 40% of all mRNA of 48-hr cells. Analysis of the 35S-labeled proteins by NaDodSO4/polyacrylamide gel electrophoresis showed that only 5-10 major polypeptides are synthesized after 30 min of rifampin treatment. One of these is protein S, the spore surface coat protein, because immunoprecipitation of the 35S-labeled proteins with antisera specific for protein S showed continued synthesis of protein S in the presence of rifampin. The half-life for its mRNA was calculated to be 15-30 min. RNA from vegetative and developing cells was pulse labeled with 32PO4 followed by rifampin treatment. Analysis of the labeled RNA on 3% NaDodSO4/polyacrylamide gels showed 5-10 long-lived mRNA bands in developing cells. These results show that there are several abundant mRNA species synthesized developmentally that are exceptionally long lived. The fact that the majority of the mRNA species show the shorter half-life suggests that developing cells retain the normal mechanism for mRNA degradation.