Zweig S, Singer S J
J Cell Biol. 1979 Feb;80(2):487-91. doi: 10.1083/jcb.80.2.487.
Concanavalin A (Con A) was taken up to a limited extent by endocytosis in rabbit reticulocytes but not in rabbit erythrocytes. This process was observed by the use of ferritin-labeled Con A and transmission electron microscopy of thin sections of plastic-embedded cells. Furthermore, the extent of endocytosis among the reticulocytes decreased with the extent of their maturation, reticulocyte age being measured by ribosome configurations. These results are consistent with the proposal that there are domains in the membranes of reticulocytes in which the Con A receptors are laterally mobile, and can be clustered and endocytosed. These mobile domains exist, or are formed, within a larger framework of immobile membrane. During reticulocyte maturation, these domains are gradually eliminated, eventually disappearing upon formation of the mature erythrocyte. Possible molecular mechanisms for this proposed elimination process are discussed.
伴刀豆球蛋白A（Con A）在兔网织红细胞中可通过内吞作用被有限摄取，但在兔红细胞中则不能。通过使用铁蛋白标记的Con A以及对塑料包埋细胞的超薄切片进行透射电子显微镜观察来监测这一过程。此外，网织红细胞内吞作用的程度随着其成熟程度的增加而降低，网织红细胞的年龄通过核糖体形态来衡量。这些结果与以下观点一致：网织红细胞膜中存在一些区域，其中Con A受体可侧向移动，能够聚集并被内吞。这些可移动区域存在于或形成于更大的不可移动膜框架内。在网织红细胞成熟过程中，这些区域逐渐被消除，最终在成熟红细胞形成时消失。文中还讨论了这种假定消除过程可能的分子机制。
