Sattar Sampurna, Addo-Quaye Charles, Thompson Gary A
College of Agricultural Sciences, The Pennsylvania State University, University Park, PA, 16802, USA.
Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA.
Plant Cell Environ. 2016 Jun;39(6):1216-27. doi: 10.1111/pce.12645. Epub 2016 Feb 10.
Resistance to Aphis gossypii in melon is attributed to the presence of the single dominant R gene virus aphid transmission (Vat), which is biologically expressed as antibiosis, antixenosis and tolerance. However, the mechanism of resistance is poorly understood at the molecular level. Aphid-induced transcriptional changes, including differentially expressed miRNA profiles that correspond to resistance interaction have been reported in melon. The potential regulatory roles of miRNAs in Vat-mediated aphid resistance were further revealed by identifying the specific miRNA degradation targets. A total of 70 miRNA:target pairs, including 28 novel miRNA:target pairs, for the differentially expressed miRNAs were identified: 11 were associated with phytohormone regulation, including six miRNAs that potentially regulate auxin interactions. A model for a redundant regulatory system of miRNA-mediated auxin insensitivity is proposed that incorporates auxin perception, auxin modification and auxin-regulated transcription. Chemically inhibiting the transport inhibitor response-1 (TIR-1) auxin receptor in susceptible melon tissues provides in vivo support for the model of auxin-mediated impacts on A. gossypii resistance.
甜瓜对棉蚜的抗性归因于单个显性R基因病毒蚜虫传播基因（Vat）的存在，该基因在生物学上表现为抗生性、抗选择性和耐受性。然而，在分子水平上，抗性机制尚不清楚。在甜瓜中已经报道了蚜虫诱导的转录变化，包括与抗性相互作用相对应的差异表达miRNA谱。通过鉴定特定的miRNA降解靶标，进一步揭示了miRNA在Vat介导的蚜虫抗性中的潜在调控作用。共鉴定出70个miRNA：靶标对，包括28个新的miRNA：靶标对，这些miRNA为差异表达的miRNA：11个与植物激素调控相关，其中6个miRNA可能调控生长素相互作用。提出了一个miRNA介导的生长素不敏感冗余调控系统模型，该模型包括生长素感知、生长素修饰和生长素调控转录。在易感甜瓜组织中化学抑制运输抑制剂响应1（TIR-1）生长素受体，为生长素介导的对棉蚜抗性影响模型提供了体内支持。
