Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
Trends Microbiol. 2021 Nov;29(11):993-1003. doi: 10.1016/j.tim.2021.02.003. Epub 2021 Feb 24.
The striking multiplicity, signal input diversity, and output specificity of c-di-GMP signaling proteins in many bacteria has brought second messenger signaling back onto the agenda of contemporary microbiology. How can several signaling pathways act in parallel in a specific manner if all of them use the same diffusible second messenger present at a certain global cellular concentration? Recent research has now shown that bacteria achieve this by flexibly combining modes of local and global c-di-GMP signaling in complex signaling networks. Three criteria have to be met to define local c-di-GMP signaling: specific knockout phenotypes, direct interactions between proteins involved, and actual cellular c-di-GMP levels remaining below the K of effectors. Adaptive changes in signaling network architecture can further enhance signaling flexibility.
许多细菌中二鸟苷酸（c-di-GMP）信号蛋白的显著多样性、信号输入多样性和输出特异性，使得第二信使信号再次成为当代微生物学的研究课题。如果所有这些信号通路都使用相同的可扩散第二信使，以特定的全局细胞浓度存在，那么它们如何以特定的方式并行作用呢？最近的研究表明，细菌通过在复杂的信号网络中灵活组合局部和全局 c-di-GMP 信号的方式来实现这一点。要定义局部 c-di-GMP 信号，需要满足三个标准：特定的敲除表型、涉及的蛋白质之间的直接相互作用以及实际的细胞 c-di-GMP 水平仍低于效应物的 K。信号网络结构的适应性变化可以进一步增强信号的灵活性。
