Kobe University Research Center for Inland Seas, Kobe 657-8501, Japan.
Protist. 2012 Sep;163(5):686-700. doi: 10.1016/j.protis.2011.09.003. Epub 2011 Nov 21.
F-actin organization during the cell cycle was investigated in two stramenopile microalgae, Ochromonas danica (Chrysophyceae; UTEX LB1298) and Heterosigma akashiwo (Raphidophyceae; NIES-6) using FITC-phalloidin. In the interphase cell of O. danica, F-actin bundles were localized forming a network structure in the cortical region, which converged from the anterior region to the posterior, whereas in the interphase cell of H. akashiwo, F-actin bundles were observed forming a network structure in the cortical region without any polarity. In both O. danica and H. akashiwo, at the initial stage of mitosis the cortical F-actin disappeared, and then during cytokinesis assembly of an actin-based ring-like structure occurred in the cell cortex in the plane of cytokinesis. The ring-like structure initiated from aster-like structures was composed of F-actin in both O. danica and H. akashiwo. Different from animal cells, later stages of cytokinesis of O. danica seemed to be promoted by microtubules, although the early stages of cytokinesis progressed with a constriction of the ring-like structure, whereas cytokinesis of H. akashiwo was apparently completed by constriction of the cell mediated by the F-actin ring, as in animal cells.
使用 FITC-鬼笔环肽研究了两种甲藻（金藻门；UTEX LB1298）和异沟藻（红藻门；NIES-6）中的有丝分裂周期中 F-肌动蛋白的组织。在 Ochromonas danica 的间期中，F-肌动蛋白束定位于皮质区域形成网络结构，从前部区域汇聚到后部，而在 Heterosigma akashiwo 的间期中，观察到 F-肌动蛋白束在皮质区域形成网络结构而没有任何极性。在 O. danica 和 H. akashiwo 中，在有丝分裂的初始阶段，皮质 F-肌动蛋白消失，然后在胞质分裂过程中，在胞质分裂平面中在细胞皮质中组装了基于肌动蛋白的环状结构。该环状结构从星状结构开始，由 O. danica 和 H. akashiwo 中的 F-肌动蛋白组成。与动物细胞不同，O. danica 的胞质分裂后期似乎由微管促进，尽管胞质分裂的早期阶段通过环状结构的收缩进行，而 H. akashiwo 的胞质分裂显然是通过 F-肌动蛋白环介导的细胞收缩完成的，与动物细胞一样。
