Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture, School of Biology and Technology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, People's Republic of China.
Sericultural Research Institute, Guangxi Zhuang Autonomous Regin, Nanning, 530007, People's Republic of China.
Biochem Genet. 2021 Apr;59(2):589-603. doi: 10.1007/s10528-020-10021-y. Epub 2021 Jan 3.
Copper (Cu) is an essential trace element for plant growth and development. It is widely involved in respiration, photosynthesis, pollen formation, and other biological processes. Therefore, low or excessive copper causes damage to plants. Mulberry is an essential perennial economic tree. At present, research on the abiotic stress responses in mulberry is mainly focused on the identification of resistant germplasm resources and cloning of resistant genes. In contrast, studies on the resistance function of microRNAs and the regulatory gene responses to stress are rare. In this study, small RNA libraries (control and copper stressed) were constructed from mulberry leaf RNA. High-throughput sequencing and screening were employed, a total of 65 known miRNAs and 78 predicted novel mature miRNAs were identified, among which 40 miRNAs were differentially expressed under copper stress. Subsequently, expression patterns were verified for 14 miRNAs by real-time fluorescence quantitative PCR (qPCR). The target genes of miRNAs were validated by 5' RLM-RACE. Our results provide the bases for further study on the molecular mechanism of copper stress regulation in mulberry.
铜（Cu）是植物生长和发育所必需的微量元素。它广泛参与呼吸、光合作用、花粉形成等生物过程。因此，铜含量过低或过高都会对植物造成损害。桑树是一种重要的多年生经济树种。目前，桑树对非生物胁迫响应的研究主要集中在抗性种质资源的鉴定和抗性基因的克隆上。相比之下，关于 microRNAs 的抗性功能和调控基因对应激的响应研究则较少。在本研究中，我们构建了桑树叶片 RNA 的小 RNA 文库（对照和铜胁迫）。通过高通量测序和筛选，共鉴定出 65 个已知的 miRNA 和 78 个预测的新成熟 miRNA，其中 40 个 miRNA 在铜胁迫下差异表达。随后，通过实时荧光定量 PCR（qPCR）验证了 14 个 miRNA 的表达模式。通过 5' RLM-RACE 验证了 miRNA 的靶基因。我们的研究结果为进一步研究桑树铜胁迫调控的分子机制提供了基础。
