Knabe W, Kuhn H J
Abteilung Morphologie, Zentrum Anatomie, Georg-August-Universität Göttingen, Germany.
J Anat. 1996 Oct;189 ( Pt 2)(Pt 2):383-91.
The translocation of mitochondria towards the primitive inner segment of the cones in the tree shrew Tupaia belangeri was investigated by transmission electron microscopy. Throughout ontogeny the migrating mitochondria were codistributed with cytoplasmic microtubules which were preserved after the application of conventional preparation techniques for transmission electron microscopy. Both the basal body of the connecting cilium and the second centriole located in the vicinity of the basal body were demonstrated to act as microtubule-organising centres (MTOCs) from which axonemal and cytoplasmic microtubules originated. The megamitochondria in the inner segment of the retinal cones of Tupaia are unique among mammals with respect to their extraordinary size and to their ordered distribution characterised by longitudinal and radial size-gradients within developing and mature cone inner segments. Thus the consistent finding of microtubules and MTOCs in the structurally polarised cones represents an extreme example of the capacity of cells to regulate the transport and distribution of organelles.
利用透射电子显微镜研究了树鼩（Tupaia belangeri）视锥细胞原始内节中线粒体的移位情况。在整个个体发育过程中，迁移的线粒体与细胞质微管共同分布，在应用传统的透射电子显微镜制备技术后，这些微管得以保留。连接纤毛的基体和位于基体附近的第二个中心粒均被证明可作为微管组织中心（MTOC），轴丝微管和细胞质微管均起源于此。树鼩视网膜视锥细胞内节中的巨型线粒体在哺乳动物中独具特色，其尺寸超常，且在发育中和成熟的视锥细胞内节中呈现出纵向和径向尺寸梯度的有序分布。因此，在结构极化的视锥细胞中持续发现微管和微管组织中心，代表了细胞调节细胞器运输和分布能力的一个极端例子。
