Rabuma Tilahun, Sanan-Mishra Neeti
Department of Biotechnology, College of Natural and Computational Science, Wolkite University, Wolkite, Ethiopia.
Plant RNAi Biology Group, International Center for Genetic Engineering and Biotechnology, New Delhi, India.
Physiol Mol Biol Plants. 2025 Jan;31(1):67-91. doi: 10.1007/s12298-025-01550-0. Epub 2025 Jan 17.
MicroRNAs (miRNAs) are endogenous, small molecules that negatively regulate gene expression to control the normal development and stress response in plants. They mediate epigenetic changes and regulate gene expression at both transcriptional and post-transcriptional levels. Synthetic biology approaches have been utilized to design efficient artificial miRNAs (amiRNAs) or target-mimics to regulate specific gene expression for understanding the biological function of genes and crop improvement. The amiRNA based gene silencing is an effective technique to "turn off" gene expression, while miRNA target-mimics or decoys are used for efficiently down regulating miRNAs and "turn on" gene expression. In this context, the development of endogenous target-mimics (eTMs) and short tandem target mimics (STTMs) represent promising biotechnological tools for enhancing crop traits like stress tolerance and disease resistance. Through this review, we present the recent developments in understanding plant miRNA biogenesis, which is utilized for the efficient design and development of amiRNAs. This is important to incorporate the artificially synthesized miRNAs as internal components and utilizing miRNA biogenesis pathways for the programming of synthetic circuits to improve crop tolerance to various abiotic and biotic stress factors. The review also examines the recent developments in the use of miRNA target-mimics or decoys for efficiently down regulating miRNAs for trait improvement. A perspective analysis and challenges on the use of amiRNAs and STTM as potent tools to engineer useful traits in plants have also been presented.
微小RNA（miRNA）是内源性小分子，可负向调控基因表达，以控制植物的正常发育和应激反应。它们介导表观遗传变化，并在转录和转录后水平调控基因表达。合成生物学方法已被用于设计高效的人工miRNA（amiRNA）或靶标模拟物，以调控特定基因的表达，从而了解基因的生物学功能并改良作物。基于amiRNA的基因沉默是一种有效“关闭”基因表达的技术，而miRNA靶标模拟物或诱饵则用于有效下调miRNA并“开启”基因表达。在此背景下，内源性靶标模拟物（eTM）和短串联靶标模拟物（STTM）的开发代表了增强作物胁迫耐受性和抗病性等性状的有前景的生物技术工具。通过本综述，我们介绍了在理解植物miRNA生物发生方面的最新进展，这被用于amiRNA的高效设计和开发。将人工合成的miRNA作为内部组件纳入，并利用miRNA生物发生途径来设计合成回路，以提高作物对各种非生物和生物胁迫因子的耐受性，这一点很重要。该综述还研究了在使用miRNA靶标模拟物或诱饵以有效下调miRNA以改良性状方面的最新进展。还对使用amiRNA和STTM作为在植物中设计有用性状的有力工具进行了前瞻性分析和挑战阐述。
