Kessel R G, Beams H W
Department of Biology, University of Iowa, Iowa City.
J Submicrosc Cytol Pathol. 1990 Jul;22(3):367-78.
Phase contrast, scanning electron microscope (SEM), and freeze fracture studies on the parasitic flagellate, Lophomonas blattarum, have demonstrated that the endomembrane system (parabasal apparatus) is highly ordered, restricted in position to a perinuclear zone at the anterior end of the organism, and is supported in this localized cytoplasmic region by overlapping sheets or plates of microtubules, previously called the calyx and axial filament, which may participate in supporting the nucleus-endomembrane system in a restricted region of the cell. Light microscope observations, SEM and freeze fracture data provide support to previous views that the rough- and smooth-surfaced endoplasmic reticulum are interconnected and attached to the outer layer of the nuclear envelope. The continuity of these membrane systems provides an orderly and restricted packing in the perinuclear cytoplasm since other areas of the cell may become filled with yeast. These flagellates are especially adept at phagocytosis of entire yeast. In yeast-laden cells, the flagella-nucleus-parabasal body-calyx-axial filament complex may separate from the remainder of the cell and assume a motile existence for a time. The significance of the described relationships, in addition to providing efficiency in endomembrane localization, may also reflect synthesis of enzymes and proteins by the RER and packaging in the SER, both of which are continuous. Granules characteristic of glycogen are concentrated around the SER which may be involved in glycogen metabolism. Although critical information is lacking, the endomembrane system may also be involved in the synthesis and morphogenesis of lysosomes, and perhaps peroxisomes. Lophomonas thus amplifies a highly ordered spatial relationship between the nuclear envelope and the ER.
对寄生鞭毛虫——蜚蠊披发虫（Lophomonas blattarum）进行的相差显微镜、扫描电子显微镜（SEM）和冷冻蚀刻研究表明，内膜系统（副基器）高度有序，位置局限于生物体前端的核周区域，并在这个局部细胞质区域由先前称为萼和轴丝的微管重叠片层或板块支撑，这些微管可能参与在细胞的受限区域支撑核内膜系统。光学显微镜观察、SEM和冷冻蚀刻数据支持了先前的观点，即粗面和滑面内质网相互连接并附着于核膜外层。这些膜系统的连续性在核周细胞质中提供了有序且受限的堆积，因为细胞的其他区域可能充满酵母。这些鞭毛虫特别擅长吞噬整个酵母。在充满酵母的细胞中，鞭毛-核-副基体-萼-轴丝复合体可能与细胞的其余部分分离，并在一段时间内以可移动的形式存在。除了在内膜定位方面提供效率外，所描述关系的意义还可能反映了粗面内质网对酶和蛋白质的合成以及滑面内质网中的包装，二者都是连续的。糖原特有的颗粒集中在可能参与糖原代谢的滑面内质网周围。尽管缺乏关键信息，但内膜系统也可能参与溶酶体，或许还有过氧化物酶体的合成和形态发生。因此，蜚蠊披发虫放大了核膜和内质网之间高度有序的空间关系。
