Abstract:
Plasmodesmata (PD) pores connect neighbouring plant cells and enable direct transport across the cell wall. Understanding the molecular composition of these structures is essential to address their formation and later dynamic regulation. Here we provide a biochemical characterisation of the cell wall co-purified with primary PD of Arabidopsis thaliana cell cultures. To achieve this result we combined subcellular fractionation, polysaccharide analyses and enzymatic fingerprinting approaches. Relative to the rest of the cell wall, specific patterns were observed in the PD fraction. Most xyloglucans, although possibly not abundant as a group, were fucosylated. Homogalacturonans displayed short methylated stretches while rhamnogalacturonan I species were remarkably abundant. Full rhamnogalacturonan II forms, highly methyl-acetylated, were also present. We additionally showed that these domains, compared to the broad wall, are less affected by wall modifying activities during a time interval of days. Overall, the protocol and the data presented here open new opportunities for the study of wall polysaccharides associated with PD.
摘要:
浆细胞(PD)孔连接相邻的植物细胞并能够直接运输穿过细胞壁。了解这些结构的分子组成对于解决它们的形成和随后的动态调节至关重要。在这里,我们提供了与拟南芥细胞培养物的原代PD共纯化的细胞壁的生化表征。为了达到这个结果,我们结合了亚细胞分馏,多糖分析和酶指纹图谱方法。相对于细胞壁的其余部分,在PD部分中观察到特定的模式。大多数木葡聚糖,虽然作为一个群体可能不丰富,被岩藻糖基化。同源半乳糖醛酸显示出短的甲基化延伸,而鼠李糖半乳糖醛酸I物种非常丰富。完整的鼠李糖半乳糖醛酸II型,高度甲基乙酰化,也在场。我们还表明,这些域,与宽阔的墙壁相比,在几天的时间间隔内,受墙壁修改活动的影响较小。总的来说,协议和这里提出的数据为研究与PD相关的壁多糖开辟了新的机会。