Abstract：
Plant microRNAs (miRNAs) control key agronomic traits that are associated with their conserved role(s) in development. However, despite a multitude of studies, the utility of miRNAs in plant-pathogen resistance remains less certain. Reviewing the literature identifies three general classes of miRNAs regarding plant pathogen defense. Firstly, a number of evolutionary dynamic 22 nucleotide miRNA families that repress large numbers of plant immunity genes, either directly, or through triggering the biogenesis of secondary siRNAs. However, understanding of their role in defense and of their manipulation to enhance pathogen resistance are still lacking. Secondly, highly conserved miRNAs that indirectly impact disease resistance through their targets that are primarily regulating development or hormone signaling. Any alteration of these miRNAs usually results in pleiotropic impacts, which may alter disease resistance in some plant species, and against some pathogens. Thirdly, are the comparatively diverse and evolutionary dynamic set of non-conserved miRNAs, some of which contribute to pathogen resistance, but whose narrow evolutionary presence will likely restrict their utility. Therefore, reflecting the diverse and evolving nature of plant-pathogen interactions, a complex interplay of plant miRNAs with pathogen responses exists. Any miRNA-based solution for pathogen resistance will likely be highly specific, rather than a general panacea.
摘要：
植物微RNA(miRNA)控制与其在发育中的保守作用相关的关键农艺性状。然而,尽管进行了大量研究，miRNAs在植物病原体抗性中的效用仍然不太确定。回顾文献确定了关于植物病原体防御的三种一般类型的miRNA。首先,许多进化动态的22个核苷酸miRNA家族，它们抑制了大量的植物免疫基因，要么直接,或通过触发次级siRNA的生物发生。然而,仍然缺乏对它们在防御中的作用以及增强病原体抗性的操作的理解。其次,高度保守的miRNA通过其主要调节发育或激素信号传导的靶标间接影响疾病抗性。这些miRNA的任何改变通常会导致多效性影响，这可能会改变一些植物的抗病性，并对抗一些病原体。第三，是相对多样化和进化动态的非保守miRNA集合，其中一些有助于病原体抗性，但其狭隘的进化存在可能会限制它们的效用。因此,反映了植物-病原体相互作用的多样性和不断发展的性质，植物miRNA与病原体反应之间存在复杂的相互作用。任何基于miRNA的病原体抗性解决方案都可能是高度特异性的，而不是一般的灵丹妙药.
