DeSilver D A, Benedict M A, Ratner D I
Department of Biology, Amherst College, MA 01002.
Biochim Biophys Acta. 1991 Jul 23;1089(3):309-19. doi: 10.1016/0167-4781(91)90170-q.
The in vivo accumulation of several prespore transcripts of Dictyostelium discoideum has previously been shown to depend upon concomitant protein synthesis (Ratner, D.I., Pentz, W.H. and Pelletier, D.A. (1989) Biochim. Biophys. Acta 1008, 71-78). Measurements of in vivo mRNA decay and nuclear run-on transcription assays have now been used to learn whether protein synthesis is required primarily for mRNA synthesis or transcript stability. The translational inhibitors cycloheximide and pactamycin stabilized existing prespore transcripts, despite their effect upon mRNA accumulation. Transcriptional assays, performed at intervals throughout the developmental cycle, demonstrated that temporal changes in the abundance of several cell-specific transcripts correlated closely with changes in their rates of synthesis. Finally, blocking protein synthesis strongly inhibited the transcription of the prespore genes examined. These results imply that one or more developmentally regulated, labile proteins are needed for the activation of prespore gene transcription.
此前已表明，盘基网柄菌几种芽孢前体转录本的体内积累依赖于伴随的蛋白质合成（Ratner, D.I., Pentz, W.H. 和 Pelletier, D.A. (1989) Biochim. Biophys. Acta 1008, 71 - 78）。现在已使用体内mRNA衰变测量和细胞核连续转录分析来了解蛋白质合成是否主要是mRNA合成或转录本稳定性所必需的。翻译抑制剂环己酰亚胺和放线菌酮稳定了现有的芽孢前体转录本，尽管它们对mRNA积累有影响。在整个发育周期中定期进行的转录分析表明，几种细胞特异性转录本丰度的时间变化与其合成速率的变化密切相关。最后，阻断蛋白质合成强烈抑制了所检测的芽孢前体基因的转录。这些结果表明，芽孢前体基因转录的激活需要一种或多种受发育调控的不稳定蛋白质。
