Thomas Clément, Tholl Stéphane, Moes Danièle, Dieterle Monika, Papuga Jessica, Moreau Flora, Steinmetz André
Plant Molecular Biology Laboratory, Centre de Recherche Public-Santé, L-1526 Luxembourg.
Cell Motil Cytoskeleton. 2009 Nov;66(11):940-57. doi: 10.1002/cm.20389.
Tight regulation of plant actin cytoskeleton organization and dynamics is crucial for numerous cellular processes including cell division, expansion and intracellular trafficking. Among the various actin regulatory proteins, actin-bundling proteins trigger the formation of bundles composed of several parallel actin filaments closely packed together. Actin bundles are present in virtually all plant cells, but their biological roles have rarely been addressed directly. However, decades of research in the plant cytoskeleton field yielded a bulk of data from which an overall picture of the functions supplied by actin bundles in plant cells emerges. Although plants lack several equivalents of animal actin-bundling proteins, they do possess major bundler classes including fimbrins, villins and formins. The existence of additional players is not excluded as exemplified by the recent characterization of plant LIM proteins, which trigger the formation of actin bundles both in vitro and in vivo. This apparent functional redundancy likely reflects the need for plant cells to engineer different types of bundles that act at different sub-cellular locations and exhibit specific function-related properties. By surveying information regarding the properties of plant actin bundles and their associated bundling proteins, the present review aims at clarifying why and how plants make actin bundles.
植物肌动蛋白细胞骨架组织和动力学的严格调控对于包括细胞分裂、扩展和细胞内运输在内的众多细胞过程至关重要。在各种肌动蛋白调节蛋白中，肌动蛋白成束蛋白触发由几根紧密排列在一起的平行肌动蛋白丝组成的束的形成。肌动蛋白束几乎存在于所有植物细胞中，但其生物学作用很少被直接探讨。然而，植物细胞骨架领域数十年的研究产生了大量数据，从中可以看出植物细胞中肌动蛋白束所发挥功能的整体情况。尽管植物缺乏几种与动物肌动蛋白成束蛋白相对应的蛋白，但它们确实拥有主要的成束蛋白类别，包括丝束蛋白、绒毛蛋白和formin。不排除存在其他相关蛋白，最近对植物LIM蛋白的表征就证明了这一点，该蛋白在体外和体内都能触发肌动蛋白束的形成。这种明显的功能冗余可能反映了植物细胞构建不同类型束的需求，这些束在不同的亚细胞位置起作用并表现出与特定功能相关的特性。通过审视有关植物肌动蛋白束及其相关成束蛋白特性的信息，本综述旨在阐明植物为何以及如何形成肌动蛋白束。
