Hallberg R L, Sutton C A
J Cell Biol. 1977 Oct;75(1):268-76. doi: 10.1083/jcb.75.1.268.
We have examined the ribosomal structural proteins isolated from vegetatively growing Tetrahymena pyriformis and from cells that had been starved of all nutrients for 24 h. Reproducible, nonartifactual differences in protein complement, primarily associated with the large ribosomal subunit, were found. The kinetics of change in ribosomal protein complement were followed both in refed and in newly starved cells. Furthermore, attempts at correlating a certain protein "phenotype" with a particular functional state of the ribosome were made. It was concluded that the alterations seen could not be correlated with a specific stage in the normal ribosome cycle. We did show, however, that the change in protein complement could occur as a result of altering preexisting ribosomes. In addition, we showed that the change correlates with a decrease in growth rate rather than being caused by the starvation conditions themselves. Speculations as to the functional significance of the protein changes are presented.
我们研究了从营养生长状态的梨形四膜虫以及饥饿24小时、缺乏所有营养物质的细胞中分离出的核糖体结构蛋白。发现了蛋白质组成上可重复的、非人为的差异，这些差异主要与核糖体大亚基相关。在重新喂食的细胞和新饥饿的细胞中都追踪了核糖体蛋白质组成的变化动力学。此外，还尝试将某种蛋白质“表型”与核糖体的特定功能状态联系起来。得出的结论是，所观察到的变化与正常核糖体循环中的特定阶段无关。然而，我们确实表明，蛋白质组成的变化可能是由于改变已有的核糖体而发生的。此外，我们还表明，这种变化与生长速率的降低相关，而不是由饥饿条件本身引起的。文中还对蛋白质变化的功能意义进行了推测。
