Department of Food Science, Shenyang Agricultural University, Shenyang 110866, PR China; College of Food Science and Engineering, Shanxi Agricultural University, Taigu, Shanxi 030801, PR China.
Department of Food Science, Shenyang Agricultural University, Shenyang 110866, PR China.
Food Res Int. 2019 Feb;116:942-952. doi: 10.1016/j.foodres.2018.09.031. Epub 2018 Sep 10.
Cold storage is commonly employed to delay senescence in 'Nanguo' pear after harvest. However, this technique also causes fruit aroma weakening. MicroRNAs are regulators of gene expression at the post-transcriptional level that play important roles in plant development and in eliciting responses to abiotic environmental stressors. In this study, the miRNA transcript profiles of the fruit on the first day (C0, LT0) move in and out of cold storage and the optimum tasting period (COTP, LTOTP) during shelf life at room temperature and after cold storage were analyzed, respectively. 314 known miRNAs were identified in 'Nanguo' pear; 176 and 135 miRNAs were significantly differentially expressed on the C0 vs. LT0 and on the COTP vs. LTOTP, respectively. After prediction the target genes of these differentially expressed miRNAs, 9 s-lipoxygenase (LOX2S), 13 s-lipoxygenase (LOX1_5), hydroperoxide lyase (HPL), and alcohol dehydrogenase (ADH1) were found differentially expressed, which were the key genes during aroma formation. The expression pattern of these target genes and the related miRNAs were identified by RT-PCR. mdm-miR172a-h, mdm-miR159a/b, mdm-miR160a-e, mdm-miR395a-i, mdm-miR399a/b/c, mdm/ppe-miR535a/b, and mdm-miR7120a/b may negatively regulate the target genes expression. These results indicate that miRNAs may play key roles in aroma weakening in cold storage 'Nanguo' pear and provide valuable information for studying the molecular mechanisms of miRNAs in the aroma weakening of fruit due to low temperature.
冷藏通常用于延缓采后‘南国’梨的衰老。然而，这种技术也会导致果实香气减弱。miRNA 是基因表达的转录后调控因子，在植物发育和对非生物环境胁迫的响应中发挥重要作用。在这项研究中，分别分析了果实进入和离开冷藏以及在货架期（COTP，LTOTP）在室温下和冷藏后的最佳品尝期（COTP，LTOTP）的第一天（C0，LT0）的 miRNA 转录谱。在‘南国’梨中鉴定出 314 个已知的 miRNA；C0 与 LT0 相比和 COTP 与 LTOTP 相比，分别有 176 个和 135 个 miRNA 差异表达。预测这些差异表达 miRNA 的靶基因后，发现 9-脂氧合酶（LOX2S）、13-脂氧合酶（LOX1_5）、过氧化物裂解酶（HPL）和醇脱氢酶（ADH1）差异表达，它们是香气形成过程中的关键基因。通过 RT-PCR 鉴定了这些靶基因和相关 miRNA 的表达模式。mdm-miR172a-h、mdm-miR159a/b、mdm-miR160a-e、mdm-miR395a-i、mdm-miR399a/b/c、mdm/ppe-miR535a/b 和 mdm-miR7120a/b 可能负调控靶基因的表达。这些结果表明，miRNA 可能在冷藏‘南国’梨香气减弱中发挥关键作用，为研究低温引起的果实香气减弱中 miRNA 的分子机制提供了有价值的信息。
