Glyphosate is the most widely used herbicide in world agriculture and for general vegetation control in a wide range of situations. Global and often intensive glyphosate selection of very large weedy plant populations has resulted in widespread glyphosate resistance evolution in populations of many weed species. Here, working with a glyphosate-resistant (GR) Echinochloa colona population that evolved in a Western Australia agricultural field, we identified an ATP-binding cassette (ABC) transporter (EcABCC8) that is consistently up-regulated in GR plants. When expressed in transgenic rice, this EcABCC8 transporter endowed glyphosate resistance. Equally, rice, maize, and soybean overexpressing the EcABCC8 ortholog genes were made resistant to glyphosate. Conversely, CRISPR/Cas9-mediated knockout of the EcABCC8 ortholog gene OsABCC8 increased rice susceptibility to glyphosate. Subcellular localization analysis and quantification of glyphosate cellular levels in treated ABCC8 transgenic rice plants and isolated leaf protoplasts as well as structural modeling support that EcABCC8 is likely a plasma membrane–localized transporter extruding cytoplasmic glyphosate to the apoplast, lowering the cellular glyphosate level. This is a report of a membrane transporter effluxing glyphosate in a GR plant species, and its function is likely conserved in crop plant species.

草甘膦是世界农业中使用最广泛的除草剂，可用于多种情况下的一般植被控制。对非常大的杂草植物种群进行全球且通常是密集的草甘膦选择，导致许多杂草物种种群中出现了广泛的草甘膦抗性进化。在这里，我们使用在西澳大利亚农田中进化的抗草甘膦 (GR)稗草种群，鉴定了一种 ATP 结合盒 (ABC) 转运蛋白 ( EcABCC8 )，它在 GR 植物中持续上调。当在转基因水稻中表达时，这种EcABCC8转运蛋白赋予了草甘膦抗性。同样，过表达EcABCC8 的水稻、玉米和大豆直向同源基因对草甘膦具有抗性。相反，CRISPR/Cas9 介导的EcABCC8直向同源基因OsABCC8 的敲除增加了水稻对草甘膦的敏感性。亚细胞定位分析和量化处理过的ABCC8转基因水稻植物和分离的叶原生质体中草甘膦细胞水平以及结构模型支持 EcABCC8 可能是质膜定位的转运蛋白，将细胞质草甘膦挤压到质外体，降低细胞草甘膦水平。这是一篇关于在 GR 植物物种中外排草甘膦的膜转运蛋白的报告，其功能在作物植物物种中可能是保守的。