Selim Khaled A, Ermilova Elena, Forchhammer Karl
Organismic Interactions Department, Interfaculty Institute of Microbiology and Infection Medicine, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany.
Biological Faculty, Saint-Petersburg State University, Universitetskaya nab. 7/9, Saint-Petersburg, 199034, Russia.
New Phytol. 2020 Aug;227(3):722-731. doi: 10.1111/nph.16492. Epub 2020 Mar 27.
The PII superfamily consists of signal transduction proteins found in all domains of life. Canonical PII proteins sense the cellular energy state through the competitive binding of ATP and ADP, and carbon/nitrogen balance through 2-oxoglutarate binding. The ancestor of Archaeplastida inherited its PII signal transduction protein from an ancestral cyanobacterial endosymbiont. Over the course of evolution, plant PII proteins acquired a glutamine-sensing C-terminal extension, subsequently present in all Chloroplastida PII proteins. The PII proteins of various algal strains (red, green and nonphotosynthetic algae) have been systematically investigated with respect to their sensory and regulatory properties. Comparisons of the PII proteins from different phyla of oxygenic phototrophs (cyanobacteria, red algae, Chlorophyta and higher plants) have yielded insights into their evolutionary conservation vs adaptive properties. The highly conserved role of the controlling enzyme of arginine biosynthesis, N-acetyl-l-glutamate kinase (NAGK), as a main PII-interactor has been demonstrated across oxygenic phototrophs of cyanobacteria and Archaeplastida. In addition, the PII signalling system of red algae has been identified as an evolutionary intermediate between that of Cyanobacteria and Chloroplastida. In this review, we consider recent advances in understanding metabolic signalling by PII proteins of the plant kingdom.
PII超家族由存在于生命所有域中的信号转导蛋白组成。典型的PII蛋白通过ATP和ADP的竞争性结合来感知细胞能量状态，并通过2-氧代戊二酸结合来感知碳/氮平衡。原始色素体生物的祖先从祖先蓝藻内共生体继承了其PII信号转导蛋白。在进化过程中，植物PII蛋白获得了一个谷氨酰胺感知C末端延伸，随后存在于所有绿藻门PII蛋白中。已经系统地研究了各种藻类菌株（红藻、绿藻和非光合藻类）的PII蛋白的传感和调节特性。对不同门的产氧光合生物（蓝细菌、红藻、绿藻门和高等植物）的PII蛋白进行比较，有助于深入了解它们的进化保守性与适应性特性。在蓝细菌和原始色素体生物的产氧光合生物中，精氨酸生物合成的控制酶N-乙酰-L-谷氨酸激酶（NAGK）作为主要的PII相互作用蛋白的高度保守作用已得到证实。此外，红藻的PII信号系统已被确定为蓝细菌和绿藻门之间的进化中间产物。在这篇综述中，我们考虑了植物王国中PII蛋白在理解代谢信号方面的最新进展。
