Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Palermo, Italy.
Department of Biology, University of Florence, Sesto Fiorentino, Italy.
Mol Biol Rep. 2019 Oct;46(5):5163-5174. doi: 10.1007/s11033-019-04974-6. Epub 2019 Jul 20.
Arbuscular mycorrhizal fungi (AMF) are soil microrganisms that establish symbiosis with plants positively influencing their resistance to abiotic stresses. The aim of this work was to identify wheat miRNAs differentially regulated by water deficit conditions in presence or absence of AMF treatment. Small RNA libraries were constructed for both leaf and root tissues considering four conditions: control (irrigated) or water deficit in presence/absence of mycorrhizal (AMF) treatment. A total of 12 miRNAs were significantly regulated by water deficit in leaves: five in absence and seven in presence of AMF treatment. In roots, three miRNAs were water deficit-modulated in absence of mycorrhizal treatment while six were regulated in presence of it. The most represented miRNA family was miR167 that was regulated by water deficit in both leaf and root tissues. Interestingly, miR827-5p was differentially regulated in leaves in the absence of mycorrhizal treatment while it was water deficit-modulated in roots irrespective of AMF treatment. In roots, water deficit repressed miR827-5p, miR394, miR6187, miR167e-3p, and miR9666b-3p affecting transcription, RNA synthesis, protein synthesis, and protein modifications. In leaves, mycorrhizae modulated miR5384-3p and miR156e-3p affecting trafficking and cell redox homeostasis. DNA replication and transcription regulation should be targeted by the repression of miR1432-5p and miR166h-3p. This work provided interesting insights into the post-transcriptional mechanisms of wheat responses to water deficit in relation to mycorrhizal symbiosis.
丛枝菌根真菌（AMF）是与植物建立共生关系的土壤微生物，积极影响植物对非生物胁迫的抗性。本研究的目的是鉴定在存在或不存在 AMF 处理的情况下，水分亏缺条件下小麦差异调控的 microRNA。考虑到四种条件：对照（灌溉）或存在/不存在菌根（AMF）处理的水分亏缺，构建了叶片和根组织的小 RNA 文库。共鉴定出 12 个 microRNA 叶片受水分亏缺显著调控：AMF 处理缺失 5 个，存在 7 个。在根中，3 个 microRNA 在不存在菌根处理的情况下受水分亏缺调节，而 6 个在存在菌根处理的情况下受调节。最具代表性的 microRNA 家族是 miR167，它在叶片和根组织中均受水分亏缺调控。有趣的是，miR827-5p 在缺乏菌根处理的叶片中差异调节，而在根中无论 AMF 处理与否，它都受水分亏缺调节。在根中，水分亏缺抑制了 miR827-5p、miR394、miR6187、miR167e-3p 和 miR9666b-3p，影响转录、RNA 合成、蛋白质合成和蛋白质修饰。在叶片中，菌根调节 miR5384-3p 和 miR156e-3p，影响运输和细胞氧化还原稳态。miR1432-5p 和 miR166h-3p 的抑制可能靶向 DNA 复制和转录调控。本研究为小麦与菌根共生关系下对水分亏缺的转录后响应机制提供了新的见解。
