The Cellular and Molecular Bases of Penetration Resistance to Fungal Pathogens in Arabidopsis

植物病害每年都对农业生产和粮食供应造成破坏性影响。 然而，为了应对病原体的攻击，大多数植物已经进化出物理和化学防御来抵御入侵。 在植物表面上，病原体渗透尝试通常通过由另外的细胞壁材料如木质素、胼胝质和结构蛋白的沉积形成的靶向细胞壁附着（CWA）来满足。 渗透抗性一直被认为是植物基础防御反应中最重要的方面之一。 最近已经鉴定了几个涉及穿透抗性的基因座，包括主要的穿透（PEN）基因（PEN 1、PEN 2和PEN 3）。 然而，在病原体渗透位点的细胞壁物质的生物合成和沉积的细胞途径仍然在很大程度上未知。 我的研究项目一直致力于了解模式植物拟南芥和作物物种对真菌病原体攻击的渗透抗性的分子和细胞机制。 我们最近的研究表明，由肌动蛋白细胞骨架调节的细胞运输介导了CWAs，并有助于穿透阻力。 拟议研究的目标是：（a）阐明在病原体穿透位点促成CWA的生物化学和分子途径，（B）理解在病原体穿透位点协调细胞壁物质的运输和沉积的细胞运输机制，以及（c）揭示参与调节宿主细胞中肌动蛋白细胞骨架动态重排的分子组分，病原体攻击 我们将应用分子生物学，细胞生物学，生物化学，遗传学和基因组学的方法沿着高通量和经典的植物病理学技术，以实现这些目标。 这项研究将导致对植物抵抗病原体攻击的防御机制的理解取得重大进展。我的研究计划也将提供宝贵的见解，设计策略，以产生持久的抗病作物对更广泛的植物病原体。

Plant diseases have a devastating impact on agricultural production and food supply every year. In response to pathogen attack, most plants however, have evolved physical and chemical defenses to ward off attempted invasions. On the plant surface, pathogen penetration attempts are often met by targeted cell wall appositions (CWAs) formed by the deposition of additional cell wall materials such as lignin, callose and structural proteins. Penetration resistance has long been recognized as one of the most prominent facets of plant basal defense responses. Several loci involved in the penetration resistance have recently been identified including major PENETRATION (PEN) genes (PEN1, PEN2, and PEN3). However, the cellular pathways underlying the biosynthesis and deposition of cell wall materials at the pathogen penetration site remain largely unknown. My research program has been devoted to understanding the molecular and cellular mechanisms of penetration resistance in the model plant Arabidopsis and crop species against fungal pathogen attack. We have recently shown that cellular trafficking regulated by the actin cytoskeleton mediates CWAs and contributes to the penetration resistance. The objectives of the proposed research are: (a) to elucidate biochemical and molecular pathways that contribute to CWAs at the pathogen penetration site, (b) to understand cellular trafficking mechanisms that coordinate transport and deposition of cell wall materials at pathogen penetration sites, and (c) to uncover molecular components that are involved in the regulation of dynamic rearrangement of the actin cytoskeleton in host cells in response to pathogen attack. We will apply molecular biology, cell biology, biochemistry, genetics, and genomics approaches along with high throughput and classical plant pathology techniques to achieve these objectives. This research will lead to significant advances in the understanding of plant defense mechanisms against pathogen attack. My research program will also provide valuable insights into designing strategies for the generation of durable disease resistant crops against a broader spectrum of plant pathogens.