The Complex Cell Wall Composition of Syncytia Induced by Plant Parasitic Cyst Nematodes Reflects Both Function and Host Plant.
The Complex Cell Wall Composition of Syncytia Induced by Plant Parasitic Cyst Nematodes Reflects Both Function and Host Plant.
复制标题
DOI：
10.3389/fpls.2017.01087
复制
发表时间：
2017
影响因子：
5.6
通讯作者：
Urwin PE
中科院分区：
文献类型：
--
作者：
Zhang L;Lilley CJ;Imren M;Knox JP;Urwin PE
植物寄生囊线虫在其寄主根部诱导形成专门的进食结构，合胞体。在整个生物营养相互作用过程中，这些独特的植物器官是发育和繁殖的唯一营养来源。多核合胞体是通过细胞壁的局部溶解和多个相邻细胞的原生质体融合而产生的，具有含有大量细胞器的致密细胞质，被增厚的外细胞壁包围，必须承受高膨胀压力。然而，关于合胞细胞壁的成分及其构象如何支持其在线虫寄生过程中的作用，人们知之甚少。我们利用一组针对一系列植物细胞壁成分的单克隆抗体，揭示了四种最具经济价值的囊线虫（Globodera pallida、Heterodera glycines、Heterodera avenae和Heterodera filipjevi）在其各自的马铃薯、大豆和春小麦寄主根系中诱导的合胞细胞壁的微观结构。原位荧光分析显示，苍白藻和甘氨酸诱导的合胞体细胞壁组成高度相似。两者都含有丰富的木葡聚糖、甲基化的均半乳糖酸和果胶阿拉伯糖。相比之下，H. avenae和H. filipjevi在小麦根系诱导的合胞体壁上含有很少的木聚糖，但富含阿魏酸木聚糖和阿拉伯糖残基，并具有不同水平的混合连锁葡聚糖。合胞细胞壁的整体化学成分反映了不同寄主植物根细胞壁的一般特征。我们将合胞细胞壁的特定成分，如丰富的阿拉伯糖、果胶均半乳糖酸的甲基酯化状态和木聚糖的阿魏酰化，与它们在形成网络以支持合胞体功能所需的强度和灵活性方面的潜在作用联系起来。
Plant–parasitic cyst nematodes induce the formation of specialized feeding structures, syncytia, within their host roots. These unique plant organs serve as the sole nutrient resource for development and reproduction throughout the biotrophic interaction. The multinucleate syncytium, which arises through local dissolution of cell walls and protoplast fusion of multiple adjacent cells, has dense cytoplasm containing numerous organelles, surrounded by thickened outer cell walls that must withstand high turgor pressure. However, little is known about how the constituents of the syncytial cell wall and their conformation support its role during nematode parasitism. We used a set of monoclonal antibodies, targeted to a range of plant cell wall components, to reveal the microstructures of syncytial cell walls induced by four of the most economically important cyst nematode species, Globodera pallida, Heterodera glycines, Heterodera avenae and Heterodera filipjevi, in their respective potato, soybean, and spring wheat host roots. In situ fluorescence analysis revealed highly similar cell wall composition of syncytia induced by G. pallida and H. glycines. Both consisted of abundant xyloglucan, methyl-esterified homogalacturonan and pectic arabinan. In contrast, the walls of syncytia induced in wheat roots by H. avenae and H. filipjevi contain little xyloglucan but are rich in feruloylated xylan and arabinan residues, with variable levels of mixed-linkage glucan. The overall chemical composition of syncytial cell walls reflected the general features of root cell walls of the different host plants. We relate specific components of syncytial cell walls, such as abundant arabinan, methyl-esterification status of pectic homogalacturonan and feruloylation of xylan, to their potential roles in forming a network to support both the strength and flexibility required for syncytium function.