BEAMS H W, KESSEL R G
J Cell Biol. 1963 Sep;18(3):621-49. doi: 10.1083/jcb.18.3.621.
The endoplasmic reticulum is composed, in places, of stacks of parallel cisternae which are limited by membranes having great numbers of ribosomes attached to their outer surface. These are connected with other cisternae of similar structure but with fewer ribosomes and without preferred orientation. The latter extend in all directions from the stacked cisternae, branching and anastomosing freely so that the entire system of membrane-limited cisternae appears interconnected; a morphological condition suitable to serve as the basis for an active transport system. Within the stacked cisternae appear granules about 40 to 60 mmicro in diameter. These are thought to represent the precursors of proteinaceous yolk, and the hypothesis is advanced that most of the intracisternal granules are synthesized here, possibly under the influence of the ribosomes. They then "flow" into and along the unoriented cisternae to regions where they collect, expand the cisternae, and undergo transformation into finely granular, relatively large proteinaceous yolk bodies. The mitochondria are somewhat pleomorphic, often show atypical cristae, and frequently contain a few dense granules. Lipid is abundant. Other cytoplasmic components are illustrated.
内质网在某些部位由平行排列的扁平囊堆叠而成，这些扁平囊由膜所界定，其外表面附着有大量核糖体。它们与其他结构相似但核糖体较少且无特定取向的扁平囊相连。后者从堆叠的扁平囊向各个方向延伸，自由分支并相互吻合，从而使整个膜界定的扁平囊系统显得相互连接；这种形态学状况适合作为主动运输系统的基础。在堆叠的扁平囊内出现直径约40至60微米的颗粒。这些颗粒被认为代表蛋白质卵黄的前体，并且有人提出假说，即大多数池内颗粒在此处合成，可能是在核糖体的影响下。然后它们“流入”并沿着无特定取向的扁平囊到达它们聚集的区域，使扁平囊扩张，并转化为细颗粒状、相对较大的蛋白质卵黄体。线粒体有些多形性，常显示出非典型的嵴，并且经常含有一些致密颗粒。脂质丰富。还展示了其他细胞质成分。
