Abstract：
Legumes enter into symbiotic associations with soil nitrogen-fixing rhizobia, culminating in the creation of new organs, root nodules. This complex process relies on chemical and physical interaction between legumes and rhizobia, including early signalling events informing the host legume plant of a potentially beneficial microbe and triggering the nodulation program. The great significance of this plant-microbe interaction rests upon conversion of atmospheric dinitrogen not accessible to plants into a biologically active form of ammonia available to plants. The plant cytoskeleton consists in a highly dynamic network and undergoes rapid remodelling upon sensing various developmental and environmental cues, including response to attachment, internalization, and accommodation of rhizobia in plant root and nodule cells. This dynamic nature is governed by cytoskeleton-associated proteins that modulate cytoskeletal behaviour depending on signal perception and transduction. Precisely localized cytoskeletal rearrangements are therefore essential for the uptake of rhizobia, their targeted delivery, and establishing beneficial root nodule symbiosis. This review summarizes current knowledge about rhizobia-dependent rearrangements and functions of the cytoskeleton in legume roots and nodules. General patterns and nodule type-, nodule stage-, and species-specific aspects of actin filaments and microtubules remodelling are discussed. Moreover, emerging evidence is provided about fine-tuning the root nodulation process through cytoskeleton-associated proteins. We also consider future perspectives on dynamic localization studies of the cytoskeleton during early symbiosis utilizing state of the art molecular and advanced microscopy approaches. Based on acquired detailed knowledge of the mutualistic interactions with microbes, these approaches could contribute to broader biotechnological crop improvement.
摘要：
豆科植物与土壤固氮根瘤菌进入共生关系，最终创造了新的器官，根瘤。这个复杂的过程依赖于豆科植物和根瘤菌之间的化学和物理相互作用，包括早期信号事件，告知宿主豆科植物潜在有益的微生物并触发结瘤程序。这种植物与微生物相互作用的重大意义在于将植物无法获得的大气二氮转化为植物可利用的生物活性形式的氨。植物细胞骨架由高度动态的网络组成，并在感知各种发育和环境线索时经历快速重塑，包括对依恋的回应，内化，根瘤菌在植物根和根瘤细胞中的调节。这种动态性质由细胞骨架相关蛋白控制，这些蛋白根据信号感知和转导调节细胞骨架行为。因此，精确定位的细胞骨架重排对于根瘤菌的摄取至关重要，他们有针对性的交付，建立有益的根瘤共生关系。这篇综述总结了有关根瘤菌依赖性重排和豆科植物根和根瘤细胞骨架功能的最新知识。一般模式和结节类型-，结节阶段-，讨论了肌动蛋白丝和微管重塑的物种特异性方面。此外，提供了关于通过细胞骨架相关蛋白微调根结瘤过程的新证据。我们还考虑了利用最先进的分子和先进的显微镜方法在早期共生过程中对细胞骨架进行动态定位研究的未来观点。基于获得的与微生物相互作用的详细知识，这些方法可能有助于更广泛的生物技术作物改良。
