Paulsson J, Ehrenberg M
Department of Cell and Molecular Biology, Uppsala University, BMC, Box 596, Uppsala, 75124 Sweden.
Phys Rev Lett. 2000 Jun 5;84(23):5447-50. doi: 10.1103/PhysRevLett.84.5447.
Many intracellular components are present in low copy numbers per cell and subject to feedback control. We use chemical master equations to analyze a negative feedback system where species X and S regulate each other's synthesis with standard intracellular kinetics. For a given number of X-molecules, S-variation can be significant. We show that this signal noise does not necessarily increase X-variation as previously thought but, surprisingly, can be necessary to reduce it below a Poissonian limit. The principle resembles Stochastic Resonance in that signal noise improves signal detection.
许多细胞内成分在每个细胞中的拷贝数较低，并受到反馈控制。我们使用化学主方程来分析一个负反馈系统，其中X和S两种物质以标准的细胞内动力学相互调节彼此的合成。对于给定数量的X分子，S的变化可能很显著。我们表明，这种信号噪声并不一定会像之前认为的那样增加X的变化，令人惊讶的是，它可能是将X的变化降低到泊松极限以下所必需的。这一原理类似于随机共振，即信号噪声可改善信号检测。
