Rabbitts P H, Watson J V, Lamond A, Forster A, Stinson M A, Evan G, Fischer W, Atherton E, Sheppard R, Rabbitts T H
EMBO J. 1985 Aug;4(8):2009-15. doi: 10.1002/j.1460-2075.1985.tb03885.x.
The presence and synthesis of c-myc protein and mRNA in the cell cycle has been studied. We find that c-myc mRNA is present, at equivalent levels, at all times in the cell cycle with the possible exception of mitosis. Furthermore, we demonstrate that this mRNA is transcribed in both G1 and G2 phases. An analysis of the c-myc protein in vivo shows that de novo synthesis occurs in G1 and G2 and the protein turns over with a half-life of approximately 20-30 min in both phases. Furthermore, the level of c-myc protein rapidly increases in cell populations when they re-initiate the cell cycle, thereafter decreasing as the culture reaches quiescence. The results therefore suggest that expression of c-myc can be rapidly modulated and that it is activated during the G0 to G1 transition, but is expressed thereafter in the cell cycle.
已对细胞周期中c-myc蛋白和mRNA的存在及合成进行了研究。我们发现，c-myc mRNA在细胞周期的所有时间均以相当的水平存在，有丝分裂期可能除外。此外，我们证明该mRNA在G1期和G2期均有转录。对体内c-myc蛋白的分析表明，从头合成发生在G1期和G2期，且该蛋白在这两个时期的半衰期约为20 - 30分钟。此外，当细胞群体重新启动细胞周期时，c-myc蛋白水平迅速升高，随后随着培养物进入静止期而降低。因此，结果表明c-myc的表达可被快速调节，且在从G0期到G1期的转变过程中被激活，但在随后的细胞周期中持续表达。
