植物细胞与细胞间物质转运及其对生长发育的调控

Cell-to-Cell Trafficking of Molecules and Its Role in the Regulation of Plant Development

细胞与细胞之间的物质运输和信号传递对于多细胞生物的生长发育非常重要.一些内源的大分子物质如蛋白质、核酸或核酸蛋白质复合体可以选择性地通过植物特有的亚细胞结构即胞间连丝(PD)在细胞之间运输.小分子物质主要以被动的形式在细胞间通过PD进行扩散.PD对蛋白质和核酸的运输具有选择性,这种运输受到严格调控.大分子物质在细胞间的运输对植物的生长和发育有极其重要的调控作用.KN1,STM,SHR,TRY和WER等转录因子在细胞之间的转运对于维持植物的茎尖分生组织、根尖分生组织和表皮细胞功能起重要作用.另外,某些小分子RNA也能够在植物细胞间进行选择性运输,并通过在不同细胞中降解或抑制靶mRNA的翻译来调节植物组织的生长发育.

Intercellular movement of molecules and signals is very important for the development of multicellular organisms. Small molecules can passively spread between cells, while endogenous macromolecules are actively transported between cells. In plant, some proteins, nucleic acids and ribonuleoproteins are able to be transported between cells through the plant-specific subceUular structure, plasmodesmata （PD）. This trafficking of endogenous macro- molecules is selective and strictly regulated, which is of tremendous importance to the plant development. KN1, STM, SHR, TRY and WER are movable transcription factors that contribute to the establishment and maintenance of plant shoot apical meristem, root apical meristem and epidermis. Besides, a number of small RNAs are reported to selectively move between plant cells and regulate plant development through their roles in the degradation or inhibition of the translation of target mRNAs.