Potter Garrett D, Byrd Tommy A, Mugler Andrew, Sun Bo
Department of Physics, Oregon State University, Corvallis, Oregon.
Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana.
Biophys J. 2017 Feb 28;112(4):795-804. doi: 10.1016/j.bpj.2016.12.045.
Cells use biochemical networks to translate environmental information into intracellular responses. These responses can be highly dynamic, but how the information is encoded in these dynamics remains poorly understood. Here, we investigate the dynamic encoding of information in the ATP-induced calcium responses of fibroblast cells, using a vectorial, or multi-time-point, measure from information theory. We find that the amount of extracted information depends on physiological constraints such as the sampling rate and memory capacity of the downstream network, and it is affected differentially by intrinsic versus extrinsic noise. By comparing to a minimal physical model, we find, surprisingly, that the information is often insensitive to the detailed structure of the underlying dynamics, and instead the decoding mechanism acts as a simple low-pass filter. These results demonstrate the mechanisms and limitations of dynamic information storage in cells.
细胞利用生化网络将环境信息转化为细胞内反应。这些反应可能高度动态，但信息如何在这些动态中编码仍知之甚少。在这里，我们使用信息论中的矢量或多时间点测量方法，研究成纤维细胞中ATP诱导的钙反应中的信息动态编码。我们发现提取的信息量取决于生理限制，如下游网络的采样率和记忆容量，并且内在噪声与外在噪声对其影响不同。通过与一个最小物理模型进行比较，令人惊讶的是，我们发现信息通常对潜在动态的详细结构不敏感，相反，解码机制起到了一个简单的低通滤波器的作用。这些结果证明了细胞中动态信息存储的机制和局限性。
