Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
National Key Facility of Crop Resources and Genetic Improvement, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Int J Mol Sci. 2023 Feb 23;24(5):4416. doi: 10.3390/ijms24054416.
Histone acetylation is the earliest and most well-characterized of post-translation modifications. It is mediated by histone acetyltransferases (HAT) and histone deacetylases (HDAC). Histone acetylation could change the chromatin structure and status and further regulate gene transcription. In this study, nicotinamide, a histone deacetylase inhibitor (HDACi), was used to enhance the efficiency of gene editing in wheat. Transgenic immature and mature wheat embryos harboring a non-mutated gene, the and a -targeting sgRNA were treated with nicotinamide in two concentrations (2.5 and 5 mM) for 2, 7, and 14 days in comparison with a no-treatment control. The nicotinamide treatment resulted in mutations in up to 36% of regenerated plants, whereas no mutants were obtained from the non-treated embryos. The highest efficiency was achieved when treated with 2.5 mM nicotinamide for 14 days. To further validate the impact of nicotinamide treatment on the effectiveness of genome editing, the endogenous gene, which is responsible for amylose synthesis, was tested. Utilizing the aforementioned nicotinamide concentration to treat embryos containing the molecular components for editing the gene, the editing efficiency could be increased to 30.3% and 13.3%, respectively, for immature and mature embryos in comparison to the 0% efficiency observed in the control group. In addition, nicotinamide treatment during transformation progress could also improve the efficiency of genome editing approximately threefold in a base editing experiment. Nicotinamide, as a novel approach, may be employed to improve the editing efficacy of low-efficiency genome editing tools such as base editing and prime editing (PE) systems in wheat.
组蛋白乙酰化是翻译后修饰中最早和研究最充分的修饰之一。它由组蛋白乙酰转移酶（HAT）和组蛋白去乙酰化酶（HDAC）介导。组蛋白乙酰化可以改变染色质结构和状态，并进一步调节基因转录。在这项研究中，烟酰胺，一种组蛋白去乙酰化酶抑制剂（HDACi），被用于提高小麦中基因编辑的效率。含有非突变基因和靶向 sgRNA 的转基因未成熟和成熟小麦胚胎在两种浓度（2.5 和 5 mM）下用烟酰胺处理 2、7 和 14 天，与未处理对照进行比较。烟酰胺处理导致高达 36%的再生植物发生突变，而未经处理的胚胎则没有突变体。当用 2.5 mM 烟酰胺处理 14 天时，效率最高。为了进一步验证烟酰胺处理对基因组编辑有效性的影响，测试了负责直链淀粉合成的内源基因。利用上述烟酰胺浓度处理含有编辑基因分子成分的胚胎，编辑效率可以分别提高到 30.3%和 13.3%，而对照组观察到的效率为 0%。此外，在转化过程中进行烟酰胺处理也可以使碱基编辑实验中的基因组编辑效率提高约三倍。烟酰胺作为一种新方法，可用于提高小麦中低效率基因组编辑工具（如碱基编辑和 prime editing (PE) 系统）的编辑效率。
