Plasmodesmata are intercellular pores connecting together most plant cells. These structures consist of a central constricted form of the endoplasmic reticulum, encircled by some cytoplasmic space, in turn delimited by the plasma membrane, itself ultimately surrounded by the cell wall. The presence and structure of plasmodesmata create multiple routes for intercellular trafficking of a large spectrum of molecules (encompassing RNAs, proteins, hormones and metabolites) and also enable local signalling events. Movement across plasmodesmata is finely controlled in order to balance processes requiring communication with those necessitating symplastic isolation. Here, we describe the identities and roles of the molecular components (specific sets of lipids, proteins and wall polysaccharides) that shape and define plasmodesmata structural and functional domains. We highlight the extensive and dynamic interactions that exist between the plasma/endoplasmic reticulum membranes, cytoplasm and cell wall domains, binding them together to effectively define plasmodesmata shapes and purposes.

疟原虫是将大多数植物细胞连接在一起的细胞间孔。这些结构由内质网的中央收缩形式组成，内质网被一些细胞质空间所包围，而细胞质空间又被质膜所界定，质膜本身最终被细胞壁所包围。疟原虫的存在和结构为多种分子（包括RNA，蛋白质，激素和代谢物）的细胞间运输创造了多种途径，也使局部信号事件成为可能。为了控制需要沟通的过程与需要进行共生分离的过程之间的平衡，可以精确控制跨等离子藻的运动。在这里，我们描述分子成分（特定组的脂质，蛋白质和壁多糖）来塑造和定义胞膜的结构和功能结构域。我们强调血浆/内质网膜，细胞质和细胞壁结构域之间存在的广泛而动态的相互作用，将它们结合在一起以有效地定义胞质的形状和目的。