IPD3 and IPD3L Function Redundantly in Rhizobial and Mycorrhizal Symbioses.
IPD3 and IPD3L Function Redundantly in Rhizobial and Mycorrhizal Symbioses.
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IPD3 和 IPD3L 在根瘤菌和菌根共生中发挥冗余作用
DOI：
10.3389/fpls.2018.00267
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发表时间：
2018
影响因子：
5.6
通讯作者：
Wang E
中科院分区：
文献类型：
--
作者：
Jin Y;Chen Z;Yang J;Mysore KS;Wen J;Huang J;Yu N;Wang E
豆科植物与固氮菌或丛枝菌根真菌形成共生关系，它们受一系列共同的共生信号途径基因调控。信号通路的中心是通过钙离子振荡激活DMI3/IPD3蛋白复合体，启动根瘤器官发生和菌根共生。DMI3是根瘤菌侵染和根瘤器官发生所必需的；然而，突变体ipd3仅在侵染线的形成中受到损害，而在紫花苜蓿根瘤器官发生中没有受到影响。我们在元宝菇基因组中发现了一个类似IPD3(IPD3L)的基因。1个ipd3l突变体表现出正常的根瘤表型。Ipd3l/ipd3-2双突变体完全不能启动侵染线和根瘤原基。当在IPD3启动子的控制下表达时，IPD3L可以在功能上取代IPD3，这表明这两个转录调控因子之间存在功能冗余。我们构建了一个与两个保守的丝氨酸残基(IPD3-2D)类似的IPD3。这足以触发根瘤器官发生，但IPD3(IPD3-8D)多位点磷酸化增加导致转录活性降低，这表明IPD3的磷酸化水平微调了其在根瘤共生中的转录活性。有趣的是，IPD3的仿磷版本在dmi3-1和dmi2-1的根上触发了自发的根状结节(DMI2是一种含有LRR的受体样激酶基因，是钙离子尖峰所必需的)，但不在野生型或ipd3l ipd3-2的根上。此外，在ipd3l ipd3-2突变体中形成了发育完全的丛枝，而在ccamk/dmi3-1突变体中没有。总之，我们的数据表明，在根瘤菌和菌根共生体中，除了IPD3和IPD3L之外，IPD3的另一个新的遗传成分或其他新的磷酸化位点在DMI3下游发挥作用。
Legume plants form symbiotic associations with either nitrogen-fixing bacteria or arbuscular mycorrhizal (AM) fungi, which are regulated by a set of common symbiotic signaling pathway genes. Central to the signaling pathway is the activation of the DMI3/IPD3 protein complex by Ca2+ oscillations, and the initiation of nodule organogenesis and mycorrhizal symbiosis. DMI3 is essential for rhizobial infection and nodule organogenesis; however, ipd3 mutants have been shown to be impaired only in infection thread formation but not in root nodule organogenesis in Medicago truncatula. We identified an IPD3-like (IPD3L) gene in the M. truncatula genome. A single ipd3l mutant exhibits a normal root nodule phenotype. The ipd3l/ipd3-2 double mutant is completely unable to initiate infection threads and nodule primordia. IPD3L can functionally replace IPD3 when expressed under the control of the IPD3 promoter, indicating functional redundancy between these two transcriptional regulators. We constructed a version of IPD3 that was phosphomimetic with respect to two conserved serine residues (IPD3-2D). This was sufficient to trigger root nodule organogenesis, but the increased multisite phosphorylation of IPD3 (IPD3-8D) led to low transcriptional activity, suggesting that the phosphorylation levels of IPD3 fine-tune its transcriptional activity in the root nodule symbiosis. Intriguingly, the phosphomimetic version of IPD3 triggers spontaneous root-like nodules on the roots of dmi3-1 and dmi2-1 (DMI2 is an LRR-containing receptor-like kinase gene which is required for Ca2+ spiking), but not on the roots of wild-type or ipd3l ipd3-2 plants. In addition, fully developed arbuscules were formed in the ipd3l ipd3-2 mutants but not the ccamk/dmi3-1 mutants. Collectively, our data indicate that, in addition to IPD3 and IPD3L, another new genetic component or other new phosphorylation sites of IPD3 function downstream of DMI3 in rhizobial and mycorrhizal symbioses.
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影响因子：
16.6
作者：
Jin Y;Liu H;Luo D;Yu N;Dong W;Wang C;Zhang X;Dai H;Yang J;Wang E
通讯作者：
Wang E
影响因子：
9.4
作者：
Chen, Caiyan;Ane, Jean-Michel;Zhu, Hongyan
通讯作者：
Zhu, Hongyan
影响因子：
11.6
作者：
Middleton, Patrick H.;Jakab, Julia;Oldroyd, Giles E. D.
通讯作者：
Oldroyd, Giles E. D.
影响因子：
7.4
作者：
Arrighi, Jean-Francois;Barre, Annick;Gough, Clare
通讯作者：
Gough, Clare
影响因子：
3.5
作者：
Boisson-Dernier, A;Chabaud, M;Barker, DG
通讯作者：
Barker, DG