Oomycetes are fungal-like eukaryotes and many of them are pathogens that threaten natural ecosystems and cause huge financial losses for the aqua- and agriculture industry. Amongst them, Aphanomyces invadans causes Epizootic Ulcerative Syndrome (EUS) in fish which can be responsible for up to 100% mortality in aquaculture. As other eukaryotic pathogens, in order to establish and promote an infection, A. invadans secretes proteins, which are predicted to overcome host defence mechanisms and interfere with other processes inside the host. We investigated the role of Lhs1 which is part of an ER-resident complex that generally promotes the translocation of proteins from the cytoplasm into the ER for further processing and secretion. Interestingly, proteomic studies reveal that only a subset of virulence factors are affected by the silencing of AiLhs1 in A. invadans indicating various secretion pathways for different proteins. Importantly, changes in the secretome upon silencing of AiLhs1 significantly reduces the virulence of A. invadans in the infection model Galleriamellonella. Furthermore, we show that AiLhs1 is important for the production of zoospores and their cluster formation. This renders proteins required for protein ER translocation as interesting targets for the potential development of alternative disease control strategies in agri- and aquaculture.

中文翻译：

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伴侣 Lhs1 有助于鱼类致病卵菌 Aphanomyces invadans 的毒力

卵菌纲是真菌样真核生物，其中许多是威胁自然生态系统并给水产和农业造成巨大经济损失的病原体。其中，入侵Aphanomyces invadans 会导致鱼类流行性溃疡综合征 (EUS)，这会导致水产养殖中高达 100% 的死亡率。与其他真核病原体一样，为了建立和促进感染，A. invadans 会分泌蛋白质，预计这些蛋白质会克服宿主防御机制并干扰宿主内部的其他过程。我们研究了 Lhs1 的作用，它是内质网驻留复合物的一部分，通常促进蛋白质从细胞质转移到内质网进行进一步加工和分泌。有趣的是，蛋白质组学研究表明，只有一部分毒力因子受到入侵 AiLhs1 沉默的影响，表明不同蛋白质的各种分泌途径。重要的是，AiLhs1 沉默后分泌组的变化显着降低了感染模型 Galleriamellonella 中入侵者的毒力。此外，我们表明 AiLhs1 对游动孢子的产生及其集群形成很重要。这使得蛋白质 ER 易位所需的蛋白质成为农业和水产养殖中替代疾病控制策略潜在发展的有趣目标。此外，我们表明 AiLhs1 对游动孢子的产生及其集群形成很重要。这使得蛋白质 ER 易位所需的蛋白质成为农业和水产养殖中替代疾病控制策略潜在发展的有趣目标。此外，我们表明 AiLhs1 对游动孢子的产生及其集群形成很重要。这使得蛋白质 ER 易位所需的蛋白质成为农业和水产养殖中替代疾病控制策略潜在发展的有趣目标。