Jerka-Dziadosz M, Strzyewska-Jówko I, Wojsa-Lugowska U, Krawczyńska W, Krzywicka A
Department of Cell Biology, M. Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw.
Protist. 2001 May;152(1):53-67. doi: 10.1078/1434-4610-00043.
The ciliate Tetrahymena thermophila possesses a multitude of cytoskeletal structures whose differentiation is related to the basal bodies - the main mediators of the cortical pattern. This investigation deals with immunolocalization using light and electron microscopy of filaments labeled by the monoclonal antibody 12G9, which in other ciliates identifies filaments involved in transmission of cellular polarities and marks cell meridians with the highest morphogenetic potential. In Tetrahymena interphase cells, mAb 12G9 localizes to the sites of basal bodies and to the striated ciliary rootlets, to the apical band of filaments and to the fine fibrillar oral crescent. We followed the sequence of development of these structures during divisional morphogenesis. The labeling of the maternal oral crescent disappears in pre-metaphase cells and reappears during anaphase, concomitantly with differentiation of the new structure in the posterior daughter cell. In the posterior daughter cell, the new apical band originates as small clusters of filaments located at the base of the anterior basal bodies of the apical basal body couplets during early anaphase. The differentiation of the band is completed in the final stages of cytokinesis and in the young post-dividing cell. The maternal band is reorganized earlier, simultaneously with the oral structure. The mAb 12G9 identifies two transient structures present only in dividing cells. One is a medial structure demarcating the two daughter cells during metaphase and anaphase, and defining the new anterior border of the posterior daughter cell. The other is a post-oral meridional filament marking the stomatogenic meridian in postmetaphase cells. Comparative analysis of immunolocalization of transient filaments labeled with mAb12G9 in Tetrahymena and other ciliates indicates that this antibody identifies a protein bound to filamentous structures, which might play a role in relying polarities of cortical domains and could be a part of a mechanism which governs the positioning of cortical organelles in ciliates.
嗜热四膜虫拥有众多细胞骨架结构，其分化与基体相关——基体是皮层模式的主要介导者。本研究利用光镜和电镜对单克隆抗体12G9标记的细丝进行免疫定位，在其他纤毛虫中，该抗体可识别参与细胞极性传递的细丝，并标记具有最高形态发生潜能的细胞子午线。在嗜热四膜虫间期细胞中，单克隆抗体12G9定位于基体部位、横纹状纤毛小根、细丝顶端带以及细纤维状口新月区。我们追踪了这些结构在分裂形态发生过程中的发育顺序。母本口新月区的标记在中期前细胞中消失，在后期重新出现，同时后仔细胞中新结构开始分化。在后仔细胞中，新的顶端带在后期早期起源于顶端基体对中前基体基部的细丝小簇。带的分化在胞质分裂的最后阶段和刚分裂后的幼细胞中完成。母本带更早进行重组，与口部结构同时发生。单克隆抗体12G9识别出仅存在于分裂细胞中的两种瞬时结构。一种是中期和后期划分两个仔细胞并界定后仔细胞新前缘的中间结构。另一种是后期细胞中标记产口子午线的口后子午线细丝。对嗜热四膜虫和其他纤毛虫中用单克隆抗体12G9标记的瞬时细丝进行免疫定位的比较分析表明，该抗体识别一种与丝状结构结合的蛋白质，它可能在传递皮层区域极性方面发挥作用，并且可能是纤毛虫中控制皮层细胞器定位机制的一部分。
