Main conclusion Rhizobium etli CE3-DsRed pMP604 drives infection 12-24 h earlier than R. etli CE3-DsRed and it is an excellent tool in live-cell imaging studies of IT developement in P. vulgaris roots. Abstract The study of the cellular dynamics of nodulation has frequently been limited by the difficulty of performing live-cell imaging in nodule primordia and legume roots, which are constituted by multiple cell layers, such is the case of Phaseolus vulgaris . Seeking conditions to reduce the time it takes for rhizobia to infect P. vulgaris root, we decided to explore the nodulation properties of Rhizobium etli CE3 pMP604, a strain that constitutively produces Nod factors through a flavonoids-independent transcriptional activation which is often used to purify Nod factors. Even though the strain infects 12–24 h earlier than the parental R. etli CE3 strain, infection thread (IT) formation, nodule organogenesis processes and N 2 -fixation activity are similar for both strains. Additionally, we have confirmed that R. etli CE3-DsRed pMP604 is an excellent tool to trace IT development in P. vulgaris roots.

中文翻译：

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根瘤菌 CE3-DsRed pMP604：研究菜豆结瘤初始感染步骤的有用生物学工具

主要结论 Rhizobium etli CE3-DsRed pMP604 比 R. etli CE3-DsRed 早 12-24 小时驱动感染，它是活细胞成像研究中 P. vulgaris 根中 IT 发育的极好工具。摘要 结瘤的细胞动力学研究经常受到在由多个细胞层构成的结节原基和豆科植物根部进行活细胞成像的难度的限制，例如菜豆。寻求条件以减少根瘤菌感染 P. vulgaris 根所需的时间，我们决定探索 Rhizobium etli CE3 pMP604 的结瘤特性，该菌株通过类黄酮非依赖性转录激活组成性地产生 Nod 因子，通常用于纯化点头因素。即使该菌株比亲本 R 早 12-24 小时感染。etli CE3菌株、感染线(IT)形成、结节器官发生过程和N 2 固定活性对于两种菌株都是相似的。此外，我们已经证实，R. etli CE3-DsRed pMP604 是追踪 P. vulgaris 根部 IT 发展的优秀工具。