A Novel Set of SNARE Partners Facilitating Bacterial Pathogen Defence

一组新的 SNARE 合作伙伴促进细菌病原体防御

• 批准号: BB/S017348/1
• 负责人: Rucha Karnik
• 金额: $ 73.65万
• 依托单位: University of Glasgow
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FS017348%2F1
• 关键词: Novel; Set; SNARE; Partners; Facilitating

Plant microbial pathogens destroy some 15% of crop production worldwide, inflicting major agricultural and socio-economic losses. Thus, understanding plant immunity is at the centre of efforts to mitigate the challenges in food production facing human society in the coming decades. Although plants have evolved defence systems, immunity comes at a cost to plant growth; crop bred to maximize growth-related traits, by contrast, often compromise on defense. To strategically maximize plant disease resistance, knowledge of the mechanisms underlying plant defences is vital to minimize reductions in yield. Stomatal pores on the leaf surface exchange gas and water with the environment and are primary entry points for microbial pathogen. The initial defence against bacterial pathogen is stomatal closure, but pathogens commonly manipulate these defences and force stomatal opening. At a cellular level, these manipulations include commandeering ion transporters and their regulatory proteins to prevent stomata closure. Microbial pathogens also hijack cellular vesicle traffic to suppress secretion of defence-related molecules to the cell wall. Secretion at the plant plasma membrane is mediated by so-called SNARE proteins that assemble to drive the final stages of membrane vesicle fusion and deliver the vesicle contents to the cell wall and space outside the cell. Yet, the knowledge of molecular basis of these processes during plant pathogenesis is sparse and virtually nothing is known of their coordination. The plasma membrane SNARE SYP132 has been associated with the secretion of antimicrobial peptides. Recently, I found that its expression and traffic within the cell are tied directly to bacterial infection. SYP132 expression, I observed, affects stomatal responses to bacterial pathogens. Furthermore, SYP132 interacts physically with the plasma membrane ion transporters and regulatory proteins that are essential for pathogen defence, and traffic of the SNARE appears to co-opt the ion transport proteins during pathogen infection. These findings point to an unexpected and central role for this SNARE as a key regulator of in stomatal defence and immunity. My hypothesis is that SYP132 endocytosis and vesicle membrane recycling are critical for early stages of bacterial pathogenesis. SYP132 traffic and functions in immunity are particularly regulated by its interactions with the ion transporters and regulatory proteins at the plasma membrane and they allow for a co-ordination between defence signalling, antimicrobial secretion and stomatal responses to fight off disease and to regulate plant-microbe interactions. I propose to elucidate the mechanisms underlying SYP132 traffic and its impact on the transporter binding partners to resolve the impact on plant immunity. These studies will make use of established plant and pathogen models as a backdrop for the work. I will determine how interactions of SYP132, particularly with the ion transporter and regulatory proteins identified to date, change during the progression of bacterial disease. I will expand the studies with proteomic analysis of the SYP132 interactome and measurement of quantitative changes in SYP132 interactions with new and known partners during bacterial pathogenesis to assess their roles in SYP132-mediated immunity. The knowledge gained will inform future efforts in approaches to engineering crops with enhanced defence systems in sustainable agriculture.

植物微生物病原体破坏了全球约15%的作物产量，造成重大的农业和社会经济损失。因此，了解植物免疫力是减轻人类社会在未来几十年面临的粮食生产挑战的核心。虽然植物已经进化出防御系统，但免疫力是以植物生长为代价的;相比之下，为了最大限度地提高与生长相关的性状而培育的作物往往会在防御上妥协。为了从战略上最大限度地提高植物抗病性，了解植物防御机制对最大限度地减少产量下降至关重要。 叶片表面的气孔与环境交换气体和水分，是微生物病原体的主要入口。细菌对病原菌的最初防御是气孔关闭，但病原菌通常操纵这些防御并迫使气孔开放。在细胞水平上，这些操纵包括征用离子转运蛋白及其调节蛋白，以防止气孔关闭。微生物病原体还劫持细胞囊泡运输以抑制防御相关分子向细胞壁的分泌。植物质膜的分泌是由所谓的SNARE蛋白介导的，这些蛋白组装以驱动膜囊泡融合的最后阶段，并将囊泡内容物递送到细胞壁和细胞外的空间。然而，在植物发病过程中这些过程的分子基础的知识是稀疏的，几乎没有什么是知道他们的协调。质膜SNARE SYP 132与抗菌肽的分泌有关。最近，我发现它在细胞内的表达和运输与细菌感染直接相关。我观察到SYP 132的表达影响气孔对细菌病原体的反应。此外，SYP 132与质膜离子转运蛋白和对病原体防御至关重要的调节蛋白发生物理相互作用，并且SNARE的运输似乎在病原体感染期间与离子转运蛋白协同作用。这些发现指出了这个陷阱作为气孔防御和免疫的关键调节器的意想不到的核心作用。我的假设是，SYP 132的内吞作用和囊泡膜再循环是细菌致病的早期阶段的关键。SYP 132在免疫中的运输和功能特别是通过其与质膜上的离子转运蛋白和调节蛋白的相互作用来调节，并且它们允许防御信号传导、抗微生物分泌和气孔响应之间的协调，以抵抗疾病并调节植物-微生物相互作用。我建议阐明SYP 132交通及其对转运蛋白结合伙伴的影响的机制，以解决对植物免疫的影响。这些研究将利用已建立的植物和病原体模型作为工作的背景。我将确定如何SYP 132的相互作用，特别是与离子转运蛋白和调节蛋白的日期，在细菌性疾病的进展过程中的变化。我将扩大研究SYP 132相互作用组的蛋白质组学分析和SYP 132与新的和已知的合作伙伴在细菌发病过程中的相互作用的定量变化的测量，以评估其在SYP 132介导的免疫作用。所获得的知识将为今后在可持续农业中采用增强防御系统的工程作物方法提供信息。

项目成果

Analyzing Protein-Protein Interactions Using the Split-Ubiquitin System.

使用分裂泛素系统分析蛋白质-蛋白质相互作用。

• DOI: 10.1007/978-1-0716-3327-4_3
• 发表时间: 2023
• 期刊: Methods in molecular biology (Clifton, N.J.)
• 作者: Karnik R

SNARE SYP132 mediates divergent traffic of plasma membrane H+-ATPase AHA1 and antimicrobial PR1 during bacterial pathogenesis.

• DOI: 10.1093/plphys/kiac149
• 发表时间: 2022-06-27
• 期刊: PLANT PHYSIOLOGY
• 影响因子: 7.4
• 作者: Baena, Guillermo;Xia, Lingfeng;Waghmare, Sakharam;Karnik, Rucha Anil
• 通讯作者: Karnik, Rucha Anil

Tri-SUS: a yeast split-ubiquitin assay to examine protein interactions governed by a third binding partner.

Tri-SUS：一种酵母分裂泛素检测，用于检查由第三个结合配偶体控制的蛋白质相互作用。

• DOI: 10.1093/plphys/kiaa039
• 发表时间: 2021
• 期刊: Plant physiology
• 影响因子: 7.4
• 作者: Zhang B