Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 50463, Republic of Korea.
College of General Education, Kookmin University, Seoul 02707, Republic of Korea.
J Proteomics. 2022 Sep 15;267:104687. doi: 10.1016/j.jprot.2022.104687. Epub 2022 Jul 30.
Pathogen-associated molecular patterns (PAMPs) play a key role in triggering PAMPs triggered immunity (PTI) in plants. In the case of the rice-Magnaporthe oryzae pathosystem, fewer PAMPs and their pattern recognition receptors (PRRs) have been characterized. Recently, a M. oryzae snodprot1 homolog protein (MSP1) has been identified that functions as PAMP and triggering the PTI responses in rice. However, the molecular mechanism underlying MSP1-induced PTI is currently elusive. Therefore, we generated MSP1 overexpressed transgenic lines of rice, and a tandem mass tag (TMT)-based quantitative membrane proteomic analysis was employed to decipher the potential MSP1-induced signaling in rice using total cytosolic as well as membrane protein fractions. This approach led to the identification of 8033 proteins of which 1826 were differentially modulated in response to overexpression of MSP1 and/or exogenous jasmonic acid treatment. Of these, 20 plasma membrane-localized receptor-like kinases (RLKs) showed increased abundance in MSP1 overexpression lines. Moreover, activation of proteins related to the protein degradation and modification, calcium signaling, redox, and MAPK signaling was observed in transgenic lines expressing MSP1 in the apoplast. Taken together, our results identified potential PRR candidates involved in MSP1 recognition and suggested the overview mechanism of the MSP1-induced PTI signaling in rice leaves. SIGNIFICANCE: In plants, recognition of pathogen pathogen-derived molecules, such as PAMPs, by plant plant-derived PRRs has an essential role for in the activation of PTI against pathogen invasion. Typically, PAMPs are recognized by plasma membrane (PM) localized PRRs, however, identifying the PM-localized PRR proteins is challenging due to their low abundance. In this study, we performed an integrated membrane protein enrichment by microsomal membrane extraction (MME) method and subsequent TMT-labeling-based quantitative proteomic analysis using MSP1 overexpressed rice. Based on these results, we successfully identified various intracellular and membrane membrane-localized proteins that participated in the MSP1-induced immune response and characterized the potential PM-localized PRR candidates in rice.
病原体相关分子模式（PAMPs）在触发植物的 PAMPs 触发免疫（PTI）中起着关键作用。在水稻-稻瘟病菌病理系统中，已经鉴定出较少的 PAMPs 和它们的模式识别受体（PRRs）。最近，已经鉴定出一种稻瘟病菌 snodprot1 同源蛋白（MSP1），它作为 PAMP 并在水稻中触发 PTI 反应。然而，目前尚不清楚 MSP1 诱导的 PTI 的分子机制。因此，我们生成了水稻的 MSP1 过表达转基因系，并采用串联质量标签（TMT）定量膜蛋白质组学分析，使用总胞质和膜蛋白部分来破译 MSP1 在水稻中诱导的信号。这种方法导致鉴定了 8033 种蛋白质，其中 1826 种在响应 MSP1 的过表达和/或外源茉莉酸处理时发生差异调节。其中，20 种质膜定位的受体样激酶（RLKs）在 MSP1 过表达系中丰度增加。此外，在表达 MSP1 的质外体的转基因系中观察到与蛋白质降解和修饰、钙信号、氧化还原和 MAPK 信号相关的蛋白质的激活。总之，我们的结果确定了参与 MSP1 识别的潜在 PRR 候选物，并提出了 MSP1 诱导的水稻 PTI 信号转导的概述机制。意义：在植物中，植物衍生的 PRR 对病原体衍生分子（如 PAMPs）的识别对于激活针对病原体入侵的 PTI 至关重要。通常，PAMPs 被质膜（PM）定位的 PRRs 识别，然而，由于其丰度低，鉴定 PM 定位的 PRR 蛋白具有挑战性。在这项研究中，我们通过微粒体膜提取（MME）方法进行了整合的膜蛋白富集，并用 MSP1 过表达水稻进行了随后的 TMT 标记定量蛋白质组学分析。基于这些结果，我们成功地鉴定了参与 MSP1 诱导免疫反应的各种细胞内和膜定位的蛋白质，并鉴定了水稻中潜在的 PM 定位的 PRR 候选物。
