Plant flotillins are required for infection by nitrogen-fixing bacteria
Plant flotillins are required for infection by nitrogen-fixing bacteria
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DOI：
10.1073/pnas.0910081107
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发表时间：
2010-01-05
影响因子：
11.1
通讯作者：
Long, Sharon R.
中科院分区：
文献类型：
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作者：
Haney, Cara H.;Long, Sharon R.
为了建立兼容的根瘤菌-豆科植物共生环境，植物根通过宿主来源的感染线索(ITS)支持细菌感染。本文报道了紫花苜蓿根瘤菌侵染豆科植物紫花苜蓿对植物FLOTLING基因(FLOT)的需求。在其他生物中，Flotillins在病毒致病、内吞和膜形成中起作用。我们鉴定了7个FLOT基因，发现其中两个，FLOT2和FLOT4，在早期共生事件中强烈上调。这种上调取决于细菌结节因子和植物感知结节因子的能力。显微镜观察数据表明，元胞杆菌FLOT2和FLOT4定位于膜微区。在根瘤菌接种后，FLOT4独特地定位于伸长的根毛的尖端。沉默FLOT2和FLOT4基因的表达揭示了在IT启动和根瘤形成过程中对这两个基因的非冗余需求。FLOT4对于IT延伸是唯一必需的，并且FLOT4定位于IT膜。这项工作揭示了植物漂浮物在共生细菌感染中的关键作用。
To establish compatible rhizobial-legume symbioses, plant roots support bacterial infection via host-derived infection threads (ITs). Here, we report the requirement of plant flotillin-like genes (FLOTs) in Sinorhizobium meliloti infection of its host legume Medicago truncatula. Flotillins in other organisms have roles in viral pathogenesis, endocytosis, and membrane shaping. We identified seven FLOT genes in the M. truncatula genome and show that two, FLOT2 and FLOT4, are strongly up-regulated during early symbiotic events. This up-regulation depends on bacterial Nod Factor and the plant's ability to perceive Nod Factor. Microscopy data suggest that M. truncatula FLOT2 and FLOT4 localize to membrane microdomains. Upon rhizobial inoculation, FLOT4 uniquely becomes localized to the tips of elongating root hairs. Silencing FLOT2 and FLOT4 gene expression reveals a nonredundant requirement for both genes in IT initiation and nodule formation. FLOT4 is uniquely required for IT elongation, and FLOT4 localizes to IT membranes. This work reveals a critical role for plant flotillins in symbiotic bacterial infection.