Bhalla Upinder S
National Centre for Biological Sciences, Gandhi Krishi Vigyan Kendra Campus, Bangalore 560065, India.
Biophys J. 2002 Aug;83(2):740-52. doi: 10.1016/S0006-3495(02)75205-3.
Networks of signaling pathways perform complex temporal decoding functions in diverse biological systems, including the synapse, development, and bacterial chemotaxis. This paper examines temporal filtering and tuning properties of synaptic signaling pathways as a possible substrate for emergent temporal decoding. A mass action kinetic model of 16 synaptic signaling pathways was used to dissect out the contribution of these pathways in linear cascades and when coupled to form a network. The model predicts two primary mechanisms of temporal tuning of pathways: a weighted summation of responses of pathways with different timings and the presence of biochemical feedback loop(s) with emergent dynamics. Regulatory inputs act differently on these two tuning mechanisms. In the first case, regulators act like a gain-control on pathways with different intrinsic tuning. In the case of feedback loops, the temporal properties of the loop itself are changed. These basic tuning mechanisms may underlie specialized temporal tuning functions in more complex signaling systems in biology.
信号通路网络在包括突触、发育和细菌趋化性在内的多种生物系统中执行复杂的时间解码功能。本文研究了突触信号通路的时间滤波和调谐特性，将其作为新兴时间解码的一种可能底物。使用一个包含16条突触信号通路的质量作用动力学模型，来剖析这些通路在线性级联反应中以及耦合形成网络时的贡献。该模型预测了通路时间调谐的两种主要机制：具有不同时间的通路响应的加权求和，以及具有新兴动力学的生化反馈环的存在。调节输入对这两种调谐机制的作用不同。在第一种情况下，调节因子对具有不同固有调谐的通路起增益控制作用。在反馈环的情况下，环本身的时间特性会发生变化。这些基本的调谐机制可能是生物学中更复杂信号系统中专门时间调谐功能的基础。
