Laboratory of Molecular Plant Physiology, Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic.
Curr Protein Pept Sci. 2011 Mar;12(2):126-36. doi: 10.2174/138920311795684940.
Multistep phosphorelay (MSP) pathways mediate a wide spectrum of adaptive responses in plants, including hormonal and abiotic stress regulations. Recent genetic evidence suggests both partial redundancy and possible functional cross-talk on the one hand and a certain level of specificity on the other. Here, we discuss recent achievements improving our understanding of possible molecular mechanisms of specificity in MSP. We consider a certain evolutionary conservation of ancestral two-component signalling systems from bacteria in a process of molecular recognition that, as we have recently shown, could be applied also to a certain extent in the case of plant MSP. Furthermore, we discuss possible roles of kinase and phosphatase activities, kinetics of both these enzymatic reactions, and phosphorylation lifetime. We include also recent findings on the expression specificity of individual members of MSP pathways and, finally, based on our recent findings, we speculate about a possible role of magnesium in regulation of MSP pathways in plants. All these mechanisms could significantly influence specificity and signalling output of the MSP pathways.
多步磷酸传递（MSP）途径介导了植物中广泛的适应性反应，包括激素和非生物胁迫调节。最近的遗传证据表明，一方面存在部分冗余和可能的功能交叉对话，另一方面存在一定程度的特异性。在这里，我们讨论了最近在提高对 MSP 特异性可能分子机制的理解方面取得的成就。我们考虑了从细菌中进化而来的祖先双组分信号系统在分子识别过程中的一定程度的保守性，正如我们最近所表明的，这种保守性在植物 MSP 的情况下在一定程度上也可以适用。此外，我们还讨论了激酶和磷酸酶活性、这两种酶反应的动力学以及磷酸化寿命的可能作用。我们还包括了关于 MSP 途径中各个成员表达特异性的最新发现，最后，根据我们最近的发现，我们推测镁可能在植物中 MSP 途径的调节中发挥作用。所有这些机制都可能显著影响 MSP 途径的特异性和信号输出。
