Melotto Maeli, Underwood William, Koczan Jessica, Nomura Kinya, He Sheng Yang
Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA.
Cell. 2006 Sep 8;126(5):969-80. doi: 10.1016/j.cell.2006.06.054.
Microbial entry into host tissue is a critical first step in causing infection in animals and plants. In plants, it has been assumed that microscopic surface openings, such as stomata, serve as passive ports of bacterial entry during infection. Surprisingly, we found that stomatal closure is part of a plant innate immune response to restrict bacterial invasion. Stomatal guard cells of Arabidopsis perceive bacterial surface molecules, which requires the FLS2 receptor, production of nitric oxide, and the guard-cell-specific OST1 kinase. To circumvent this innate immune response, plant pathogenic bacteria have evolved specific virulence factors to effectively cause stomatal reopening as an important pathogenesis strategy. We provide evidence that supports a model in which stomata, as part of an integral innate immune system, act as a barrier against bacterial infection.
微生物进入宿主组织是动植物感染过程中的关键第一步。在植物中，人们一直认为诸如气孔等微观表面开口在感染期间是细菌进入的被动通道。令人惊讶的是，我们发现气孔关闭是植物先天免疫反应的一部分，用于限制细菌入侵。拟南芥的气孔保卫细胞感知细菌表面分子，这需要FLS2受体、一氧化氮的产生以及保卫细胞特异性的OST1激酶。为了规避这种先天免疫反应，植物致病细菌已经进化出特定的毒力因子，以有效地使气孔重新开放，作为一种重要的致病策略。我们提供的证据支持了一种模型，即气孔作为完整先天免疫系统的一部分，充当抵御细菌感染的屏障。
