Extensive membrane systems at the host-arbuscular mycorrhizal fungus interface
Extensive membrane systems at the host-arbuscular mycorrhizal fungus interface
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DOI：
10.1038/s41477-019-0364-5
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发表时间：
2019-02-01
期刊：
影响因子：
18
通讯作者：
Harrison, Maria J.
中科院分区：
文献类型：
--
作者：
Ivanov, Sergey;Austin, Jotham, II;Harrison, Maria J.
在丛枝菌根（AM）共生过程中，根皮层内的细胞发育成一个充满基质的质外体室，其中分化的AM真菌菌丝称为丛枝。隔室的发育迅速发生，与真菌菌丝的细胞内渗透和快速分支一致，并且它需要植物细胞的许多分泌机制来产生界定隔室的丛枝周膜。尽管最近的进展，我们的理解的发展的丛枝周围膜和跨共生界面的分子转移是有限的。在这里，使用电子显微镜和断层扫描，我们发现，动脉周围基质包含两种类型的膜结合的隔间。我们提出，其中之一出现作为一个结果的生物发生的丛枝周围膜，并可能促进运动的分子之间的共生伙伴。此外，我们发现，丛枝包含大量的膜管阵列位于原生质体和细胞壁之间。我们推测，这些小管可能提供所需的营养同化和可能的水分吸收，使菌丝快速扩张的吸收能力。
During arbuscular mycorrhizal (AM) symbiosis, cells within the root cortex develop a matrix-filled apoplastic compartment in which differentiated AM fungal hyphae called arbuscules reside. Development of the compartment occurs rapidly, coincident with intracellular penetration and rapid branching of the fungal hypha, and it requires much of the plant cell's secretory machinery to generate the periarbuscular membrane that delimits the compartment. Despite recent advances, our understanding of the development of the periarbuscular membrane and the transfer of molecules across the symbiotic interface is limited. Here, using electron microscopy and tomography, we reveal that the periarbuscular matrix contains two types of membrane-bound compartments. We propose that one of these arises as a consequence of biogenesis of the periarbuscular membrane and may facilitate movement of molecules between symbiotic partners. Additionally, we show that the arbuscule contains massive arrays of membrane tubules located between the protoplast and the cell wall. We speculate that these tubules may provide the absorptive capacity needed for nutrient assimilation and possibly water absorption to enable rapid hyphal expansion.