The Activators of Type 2A Phosphatases (PP2A) Regulate Multiple Cellular Processes Via PP2A-Dependent and - Independent Mechanisms in Fusarium graminearum
The Activators of Type 2A Phosphatases (PP2A) Regulate Multiple Cellular Processes Via PP2A-Dependent and - Independent Mechanisms in Fusarium graminearum
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DOI：
10.1094/mpmi-03-18-0056-r
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发表时间：
2018-11-01
影响因子：
3.5
通讯作者：
Yin，Yanni
中科院分区：
文献类型：
--
作者：
Liu，Zunyong;Liu，Na;Yin，Yanni
禾谷镰刀菌（Fusarium graminearum）含有FgPp2A、FgSit4和FgPpg1三种蛋白磷酸酶，它们在真菌的生长发育和致病力中起着重要作用。在这里，我们确定了两个PP2A激活剂（PTPAs），FgRrd1和FgRrd2，并发现他们控制PP2A的活性在PP2A特异性的方式。FgRrd1与FgPpg1相互作用，但FgRrd2与FgPp2A相互作用，与FgSit4相互作用非常弱。此外，FgRrd2通过调节FgPp2A甲基化来激活FgPp2A。表型分析表明，FgRrd1和FgRrd2调节菌丝生长，分生孢子，性发育和脂滴生物合成。更重要的是，FgRrd1和FgRrd2都与RNA聚合酶II相互作用，随后在真菌毒素生物合成基因的启动子处调节其富集，这不依赖于PP2A。此外，FgRrd2通过调节高渗透压甘油途径中激酶FgHog1的磷酸化来调节对苯基吡咯杀真菌剂的反应，并通过调节FgPp2A甲基化来调节对咖啡因的反应。综上所述，本研究结果表明FgRrd1和FgRrd2通过不同的调控机制调控禾谷镰刀菌的多种生理过程，为理解PTPAs在真菌中的生物学功能提供了新的视角。
The type 2A protein phosphatases (PP2As) are holoenzymes in all eukaryotes but their activators remain unknown in filamentous fungi.Fusarium graminearumcontains three PP2As (FgPp2A, FgSit4, and FgPpg1), which play critical roles in fungal growth, development, and virulence. Here, we identified two PP2A activators (PTPAs), FgRrd1 and FgRrd2, and found that they control PP2A activity in a PP2A-specific manner. FgRrd1 interacts with FgPpg1, but FgRrd2 interacts with FgPp2A and very weakly with FgSit4. Furthermore, FgRrd2 activates FgPp2A via regulating FgPp2A methylation. Phenotypic assays showed that FgRrd1 and FgRrd2 regulate mycelial growth, conidiation, sexual development, and lipid droplet biogenesis. More importantly, both FgRrd1 and FgRrd2 interact with RNA polymerase II, subsequently modulating its enrichments at the promoters of mycotoxin biosynthesis genes, which is independent on PP2A. In addition, FgRrd2 modulates response to phenylpyrrole fungicide, via regulating the phosphorylation of kinase FgHog1 in the high-osmolarity glycerol pathway, and to caffeine, via modulating FgPp2A methylation. Taken together, results of this study indicate that FgRrd1 and FgRrd2 regulate multiple physiological processes via different regulatory mechanisms inF. graminearum, which provides a novel insight into understanding the biological functions of PTPAs in fungi.