Taillefumier Thibaud, Wingreen Ned S
Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America.
Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America; Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America.
PLoS Comput Biol. 2015 May 12;11(5):e1004238. doi: 10.1371/journal.pcbi.1004238. eCollection 2015 May.
Quorum sensing is the regulation of gene expression in response to changes in cell density. To measure their cell density, bacterial populations produce and detect diffusible molecules called autoinducers. Individual bacteria internally represent the external concentration of autoinducers via the level of monitor proteins. In turn, these monitor proteins typically regulate both their own production and the production of autoinducers, thereby establishing internal and external feedbacks. Here, we ask whether feedbacks can increase the information available to cells about their local density. We quantify available information as the mutual information between the abundance of a monitor protein and the local cell density for biologically relevant models of quorum sensing. Using variational methods, we demonstrate that feedbacks can increase information transmission, allowing bacteria to resolve up to two additional ranges of cell density when compared with bistable quorum-sensing systems. Our analysis is relevant to multi-agent systems that track an external driver implicitly via an endogenously generated signal.
群体感应是指基因表达根据细胞密度的变化进行调节。为了测量其细胞密度，细菌群体产生并检测称为自诱导物的可扩散分子。单个细菌通过监测蛋白的水平在内部表征自诱导物的外部浓度。反过来，这些监测蛋白通常会调节它们自身的产生以及自诱导物的产生，从而建立内部和外部反馈。在这里，我们要问反馈是否能增加细胞可获得的关于其局部密度的信息。对于群体感应的生物学相关模型，我们将可用信息量化为监测蛋白丰度与局部细胞密度之间的互信息。使用变分方法，我们证明反馈可以增加信息传递，与双稳态群体感应系统相比，使细菌能够分辨出多达两个额外的细胞密度范围。我们的分析适用于通过内源性产生的信号隐式跟踪外部驱动因素的多智能体系统。
