一種激酶控制稻瘟病菌通過膨壓驅動侵染
作者:
小柯機器人發布時間:2019/10/10 15:43:35
英國埃克塞特大學Nicholas J. Talbot小組研究發現,一種傳感激酶控制由稻瘟菌引起的膨壓驅動的植物感染。 這一研究成果2019年10月9日在線發表在《自然》上。
課題組人員發現,組氨酸激酶Sln1促使附著胞感受壓力達到臨界膨閾值,從而促進宿主滲透。研究人員發現Sln1傳感器以壓力依賴的方式定位於附著胞的孔,這與植物感染數學模型的預測相符。Δsln1突變體會產生過量的附著胞膨壓,產生高度黑化、無功能的附著胞,並且不會組織葉片感染所需的隔膜和極性決定因素。Sln1與蛋白激酶C通路並行起作用,通過蛋白激酶A來調節cAMP依賴的信號通路。 Pkc1磷酸化NADPH氧化酶的調節分子NoxR。總的來說,這些信號通路調節附著胞膨壓並觸發生成入侵力量引起枯萎病。
研究人員表示,稻瘟病菌進入其寄主植物通過專門的增壓感染細胞,稱為附著胞,其物理性斷裂葉角質層。膨壓通過胞裂蛋白介導的細胞骨架重組,和肌動蛋白依賴的菌絲的突出來施加巨大的入侵力。然而,在附著胞介導的植物感染過程中,調節膨大壓力產生的分子機制仍然知之甚少。
附:英文原文
Title: A sensor kinase controls turgor-driven plant infection by the rice blast fungus
Author: Lauren S. Ryder, Yasin F. Dagdas, Michael J. Kershaw, Chandrasekhar Venkataraman, Anotida Madzvamuse, Xia Yan, Neftaly Cruz-Mireles, Darren M. Soanes, Miriam Oses-Ruiz, Vanessa Styles, Jan Sklenar, Frank L. H. Menke, Nicholas J. Talbot
Issue&Volume: 2019-10-09
Abstract:
The blast fungus Magnaporthe oryzae gains entry to its host plant by means of a specialized pressure-generating infection cell called an appressorium, which physically ruptures the leaf cuticle1,2. Turgor is applied as an enormous invasive force by septin-mediated reorganization of the cytoskeleton and actin-dependent protrusion of a rigid penetration hypha3. However, the molecular mechanisms that regulate the generation of turgor pressure during appressorium-mediated infection of plants remain poorly understood. Here we show that a turgor-sensing histidine–aspartate kinase, Sln1, enables the appressorium to sense when a critical turgor threshold has been reached and thereby facilitates host penetration. We found that the Sln1 sensor localizes to the appressorium pore in a pressure-dependent manner, which is consistent with the predictions of a mathematical model for plant infection. A Δsln1 mutant generates excess intracellular appressorium turgor, produces hyper-melanized non-functional appressoria and does not organize the septins and polarity determinants that are required for leaf infection. Sln1 acts in parallel with the protein kinase C cell-integrity pathway as a regulator of cAMP-dependent signalling by protein kinase A. Pkc1 phosphorylates the NADPH oxidase regulator NoxR and, collectively, these signalling pathways modulate appressorium turgor and trigger the generation of invasive force to cause blast disease.
DOI: 10.1038/s41586-019-1637-x
Source: https://www.nature.com/articles/s41586-019-1637-x