Corteva Agriscience, Johnston, IA, USA.
MyFloraDNA, Woodland, CA, USA.
Nat Plants. 2023 Feb;9(2):255-270. doi: 10.1038/s41477-022-01338-0. Epub 2023 Feb 9.
Transformation in grass species has traditionally relied on immature embryos and has therefore been limited to a few major Poaceae crops. Other transformation explants, including leaf tissue, have been explored but with low success rates, which is one of the major factors hindering the broad application of genome editing for crop improvement. Recently, leaf transformation using morphogenic genes Wuschel2 (Wus2) and Babyboom (Bbm) has been successfully used for Cas9-mediated mutagenesis, but complex genome editing applications, requiring large numbers of regenerated plants to be screened, remain elusive. Here we demonstrate that enhanced Wus2/Bbm expression substantially improves leaf transformation in maize and sorghum, allowing the recovery of plants with Cas9-mediated gene dropouts and targeted gene insertion. Moreover, using a maize-optimized Wus2/Bbm construct, embryogenic callus and regenerated plantlets were successfully produced in eight species spanning four grass subfamilies, suggesting that this may lead to a universal family-wide method for transformation and genome editing across the Poaceae.
传统上，草物种的转化依赖于未成熟的胚胎，因此仅限于少数几种主要的禾本科作物。其他转化外植体，包括叶组织，也已经被探索过，但成功率很低，这是阻碍基因组编辑在作物改良中广泛应用的主要因素之一。最近，使用形态发生基因 Wuschel2（Wus2）和 Babyboom（Bbm）的叶片转化已成功用于 Cas9 介导的诱变，但需要大量再生植物进行筛选的复杂基因组编辑应用仍然难以实现。在这里，我们证明了增强的 Wus2/Bbm 表达显著提高了玉米和高粱的叶片转化效率，允许恢复 Cas9 介导的基因缺失和靶向基因插入的植物。此外，使用优化的玉米 Wus2/Bbm 构建体，成功地在跨越四个禾本科亚科的八个物种中产生了胚性愈伤组织和再生小植株，这表明这可能导致在整个禾本科范围内进行转化和基因组编辑的通用方法。
