Department of Biochemistry, University of Oxford, Oxford OX1 3QU, England, UK.
J Cell Biol. 2011 Jul 11;194(1):121-35. doi: 10.1083/jcb.201103160.
Cytoskeletal organization is central to establishing cell polarity in various cellular contexts, including during messenger ribonucleic acid sorting in Drosophila melanogaster oocytes by microtubule (MT)-dependent molecular motors. However, MT organization and dynamics remain controversial in the oocyte. In this paper, we use rapid multichannel live-cell imaging with novel image analysis, tracking, and visualization tools to characterize MT polarity and dynamics while imaging posterior cargo transport. We found that all MTs in the oocyte were highly dynamic and were organized with a biased random polarity that increased toward the posterior. This organization originated through MT nucleation at the oocyte nucleus and cortex, except at the posterior end of the oocyte, where PAR-1 suppressed nucleation. Our findings explain the biased random posterior cargo movements in the oocyte that establish the germline and posterior.
细胞骨架组织对于在各种细胞环境中建立细胞极性至关重要，包括在果蝇卵母细胞中通过微管（MT）依赖性分子马达进行信使核糖核酸（mRNA）分拣的过程中。然而，卵母细胞中的 MT 组织和动力学仍然存在争议。在本文中，我们使用新型的多通道活细胞成像和图像分析、跟踪和可视化工具来描述 MT 极性和动力学，同时对后部货物运输进行成像。我们发现卵母细胞中的所有 MT 都具有高度动态性，并呈现出向后部倾斜的随机极性。这种组织起源于卵母细胞核和皮质处的 MT 成核，除了卵母细胞的后端，那里的 PAR-1 抑制了成核。我们的发现解释了卵母细胞中偏向随机的后部货物运动，这些运动建立了生殖系和后部。
