2020年10月12日出版的《自然—生物技术》杂志发表了美国加州大学戴维斯分校Jorge Dubcovsky课题组的一项最新研究成果。该团队的研究开发出了GRF-GIF嵌合蛋白，可提高转基因植物的再生效率。

研究团队表明由小麦生长调节因子4（GRF4）及其辅因子GRF相互作用因子1（GIF1）组成的融合蛋白的表达能够显著提高小麦，黑小麦和水稻的再生效率和再生速度，并增加了可转化小麦的基因型数量。GRF4-GIF1转基因植物是肥沃的,没有明显的发育缺陷。

此外，GRF4-GIF1在不存在外源性细胞分裂素的情况下诱导了小麦的高效再生，这有助于选择无选择标记的转基因植物。该课题组人员还将GRF4-GIF1和CRISPR-Cas9基因组编辑相结合，生成了30个编辑过的基因Q(AP2L-A5)破坏的小麦植物。最后，小组表明双子叶植物的GRF-GIF嵌合体能够提高柑橘类的再生效率，表明该策略可以应用于双子叶植物作物。

据悉，潜在的基因组编辑能够改善农艺作物的性能，但通常受限于植物再生效率低和可转化基因型少的问题。

附：英文原文

Title: A GRF–GIF chimeric protein improves the regeneration efficiency of transgenic plants

Author: Juan M. Debernardi, David M. Tricoli, Maria F. Ercoli, Sadiye Hayta, Pamela Ronald, Javier F. Palatnik, Jorge Dubcovsky

Issue&Volume: 2020-10-12

Abstract: The potential of genome editing to improve the agronomic performance of crops is often limited by low plant regeneration efficiencies and few transformable genotypes. Here, we show that expression of a fusion protein combining wheat GROWTH-REGULATING FACTOR 4 (GRF4) and its cofactor GRF-INTERACTING FACTOR 1 (GIF1) substantially increases the efficiency and speed of regeneration in wheat, triticale and rice and increases the number of transformable wheat genotypes. GRF4–GIF1 transgenic plants were fertile and without obvious developmental defects. Moreover, GRF4–GIF1 induced efficient wheat regeneration in the absence of exogenous cytokinins, which facilitates selection of transgenic plants without selectable markers. We also combined GRF4–GIF1 with CRISPR–Cas9 genome editing and generated 30 edited wheat plants with disruptions in the gene Q (AP2L-A5). Finally, we show that a dicot GRF–GIF chimera improves regeneration efficiency in citrus, suggesting that this strategy can be applied to dicot crops.

DOI: 10.1038/s41587-020-0703-0

Source: https://www.nature.com/articles/s41587-020-0703-0