Institute of Biotechnology, Fujian Academy of Agricultural Sciences/Fujian Provincial Key Laboratory of Genetic Engineering for Agriculture, Fuzhou, China.
Xiamen Key Laboratory for Plant Genetics, School of Life Sciences, Xiamen University, Xiamen, China.
J Exp Bot. 2021 Oct 26;72(20):7067-7077. doi: 10.1093/jxb/erab336.
MicroRNAs (miRNAs) target specific mRNA molecules based on sequence complementarity for their degradation or repression of translation, thereby regulating various developmental and physiological processes in eukaryotic organisms. Expressing the target mimicry (MIM) and short tandem target mimicry (STTM) can block endogenous activity of mature miRNAs and eliminate the inhibition of their target genes, resulting in phenotypic changes due to higher expression of the target genes. Here, we report a strategy to achieve derepression of interested miRNA-target genes through CRISPR/Cas9-based generation of in-frame mutants within the miRNA-complementary sequence of the target gene. We show that two rice genes, OsGRF4 (GROWTH REGULATING FACTOR 4) and OsGRF8 carrying in-frame mutants with disruption of the miR396 recognition sites, escape from miR396-mediated post-transcriptional silencing, resulting in enlarged grain size and increase in brown planthopper (BPH) resistance, in their respective transgenic rice lines. These results demonstrate that CRISPR/Cas9-mediated disruption of miRNA target sites can be effectively employed to precisely derepress particular target genes of functional importance for trait improvement in plants.
微小 RNA（miRNAs）基于序列互补性靶向特定的 mRNA 分子，降解或抑制其翻译，从而调节真核生物的各种发育和生理过程。表达靶 mimicry（MIM）和短串联靶 mimicry（STTM）可以阻断成熟 miRNAs 的内源性活性，并消除对其靶基因的抑制，导致靶基因表达升高而产生表型变化。在这里，我们报告了一种通过 CRISPR/Cas9 技术在靶基因的 miRNA 互补序列内产生框内突变来实现感兴趣的 miRNA-靶基因去抑制的策略。我们表明，两个水稻基因，OsGRF4（生长调节因子 4）和 OsGRF8，携带 miR396 识别位点中断的框内突变，逃避 miR396 介导的转录后沉默，导致粒型增大和褐飞虱（BPH）抗性增加，在各自的转基因水稻系中。这些结果表明，CRISPR/Cas9 介导的 miRNA 靶位点的破坏可以有效地用于精确去抑制对植物性状改良具有重要功能的特定靶基因。
Zotero 插件
