微丝-肌球蛋白-胞质环流与棉纤维极性生长

棉花纤维的极性生长是棉花品质形成的关键。同时，棉花纤维细胞作为一种极度伸长的单细胞，一直是研究植物细胞极性生长的理想模型。在植物细胞的极性伸长过程中，微丝骨架的组织、肌球蛋白介导的囊泡运输以及由此产生的胞质环流都发挥了重要的功能。然而由于缺乏直接的活细胞证据，在棉花纤维细胞中的相关研究还几乎是一片空白。我们课题组前期活细胞显微成像分析，发现棉花纤维呈向顶的扩散性生长模式。本课题将进一步探究棉花纤维中的微丝骨架动态组织特性，同时也聚焦于肌球蛋白介导的囊泡运输及产生的胞质环流在棉花纤维极性生长的作用。并通活细胞的观察以及计算机模拟分析，深入解析“微丝骨架-肌球蛋白-胞质环流”所形成的三维交互网络。这些结果将为阐明植物细胞极性伸长的细胞驱动力、遗传改良棉花纤维品质提供重要理论依据。

Cotton fibers, have been regarded as an ideal highly elongated single cell model for plant cell polar growth. Highly polarized elongation of cotton fibers is a determine factor for fiber length, one of the most important indexes of fiber quality. Dynamic organization of actin filaments, and the myosin-mediated vesicle trafficking and the cytoplasmic streaming are considered to play vital roles during plant cell polarity elongation. However, lacking of direct evidences in living cells, cellular mechanisms for cotton fiber polar growth remain largely unknown. Our group has uncovered the tip-biased diffuse growth mode for cotton fibers using living cell imaging. In this study, we are going to further explore the dynamic behavior of actin filaments, as well as the myosin-directed vesicle trafficking and cytoplasmic streaming during cotton fiber development. Combining the living cell observation and computational modeling to Illuminate the three-dimensional interactive network of the “actin filaments-myosin-cytoplasmic streaming” system. These results will provide important insights into the clarification of the driven force for polar growth in plant cells. Moreover, it provides important theoretical basis for genetic improvement of cotton fiber quality.