Abstract:
Phytophthora sojae is a widely distributed, destructive oomycete plant pathogen that has been developed as a model for oomycete biology. Given the important but limited reports on the comparison of the sexual and asexual stages in Phytophthora, we performed a large-scale quantitative proteomics study on two key asexual life stages of P. sojae-the mycelium and cyst-as well as on the oospore, which is a key sexual stage. Over 29,631 peptides from 4688 proteins were analyzed. Briefly, 445 proteins, 624 proteins, and 579 proteins were defined as differentially quantified proteins in cyst vs mycelium, oospore vs cyst, and oospore vs mycelium comparisons, respectively (|log2 fold change| > 1 and P < 0.05). Compared to the mycelium and oospore, fatty acid and nitrogen metabolism were specifically induced in cysts. In oospores, the up-regulated proteins focused on RNA transport and protein processing in endoplasmic reticulum, indicating translation, folding, and the secretion of core cellular or stage-specific proteins active in oospores, which might be used for oospore germination. The data presented expand our knowledge of pathways specifically linked to asexual and sexual stages of this pathogen. BIOLOGICAL SIGNIFICANCE: The sexual spores (oospores) in oomycetes have thick cell walls and can survive in the soil for years, thus providing a primary source and allowing the reinfection of their host plant in subsequent growing seasons. However, the proteomic study on oospores remains very limited as they are generally considered to be dormant. In the present study, we successfully isolated oospores, and performed a large-scale comparative quantitative proteomics study on this key sexual stage and two representative asexual stages of P. sojae. The results provide an improved understanding of P. sojae biology and suggest potential metabolic targets for disease control at the three different developmental stages in oomycetes.
摘要:
大豆疫霉是一种分布广泛的,已开发为卵菌生物学模型的破坏性卵菌植物病原体。鉴于关于疫霉性和无性阶段比较的重要但有限的报道,我们对大豆芽孢杆菌的两个关键无性生命阶段-菌丝体和囊肿-以及卵孢子进行了大规模的定量蛋白质组学研究,这是一个关键的性阶段。分析了来自4688个蛋白质的超过29,631个肽。简而言之,445种蛋白质,624个蛋白质,579种蛋白质被定义为囊肿与菌丝体中差异定量的蛋白质,卵孢子与囊肿,和卵孢子与菌丝体的比较,分别为(|log2倍数变化|>1和P<0.05)。与菌丝体和卵孢子相比,在囊肿中特异性诱导脂肪酸和氮代谢。在卵孢子中,上调的蛋白质集中在内质网的RNA转运和蛋白质加工,指示翻译,折叠,分泌卵孢子中具有活性的核心细胞或阶段特异性蛋白质,可用于卵孢子萌发。所提供的数据扩展了我们对与该病原体的无性和性阶段特别相关的途径的了解。生物学意义:卵菌中的性孢子(卵孢子)具有厚厚的细胞壁,可以在土壤中存活多年,从而提供了主要来源,并允许在随后的生长季节中重新感染其寄主植物。然而,卵孢子的蛋白质组学研究仍然非常有限,因为它们通常被认为是休眠的。在本研究中,我们成功地分离了卵孢子,并对该关键性阶段和两个代表性的无性阶段进行了大规模的比较定量蛋白质组学研究。结果提供了对大豆假单胞菌生物学的更好理解,并为卵菌在三个不同发育阶段的疾病控制提供了潜在的代谢目标。