Pierce G B, Jones A, Orfanakis N G, Nakane P K, Lustig L
Differentiation. 1982;23(1):60-72. doi: 10.1111/j.1432-0436.1982.tb01267.x.
The biosynthesis of basement membrane (Reichert's membrane) by parietal yolk sac cells of the mouse embryo was studied using immunohistochemistry and autoradiography with the electron microscope. Fab' fragments of characterized antisera to either a mixture of type IV collagen and laminin, or to type IV collagen alone, were conjugated to horseradish peroxidase for the immunohistochemical study; radiolabeled proline, leucine, and glucosamine were utilized either in vivo or in isolated yolk sac membranes in vitro for autoradiography. Whereas neither of the two antisera employed localized in either the Golgi apparatus or in the cytosol, both localized in the rough endoplasmic reticulum (RER) and in the extracellular basement membrane. Furthermore, no evidence of passage of isotopically labeled precursors of basement membrane from the RER to the Golgi apparatus was observed. Consequently, it is concluded that the basement membrane precursors are synthesized in the RER of parietal yolk sac cells and neither traverse the Golgi apparatus nor diffuse across the cytosol of the cell in the process of secretion. By elimination, secretion must be via direct communications between RER and plasma membrane or via small vesicles observed in the cytosol between RER and plasma membrane. These data are not in accord with the concept of the universality of the Golgi apparatus in the biosynthesis of glycoprotein. Parietal yolk sac cells do not use the Golgi apparatus in the biosynthesis of basement membrane, but do use the Golgi apparatus for the biosynthesis of other proteins.
利用免疫组织化学和电子显微镜放射自显影技术，研究了小鼠胚胎壁层卵黄囊细胞合成基底膜（雷氏膜）的过程。将针对IV型胶原蛋白和层粘连蛋白混合物或单独针对IV型胶原蛋白的特异性抗血清的Fab'片段与辣根过氧化物酶偶联，用于免疫组织化学研究；放射性标记的脯氨酸、亮氨酸和氨基葡萄糖在体内或体外分离的卵黄囊膜中用于放射自显影。所用的两种抗血清均未定位在高尔基体或细胞质中，而是都定位在粗面内质网（RER）和细胞外基底膜中。此外，未观察到基底膜同位素标记前体从RER转运至高尔基体的证据。因此，得出结论，基底膜前体在壁层卵黄囊细胞的RER中合成，在分泌过程中既不穿过高尔基体也不扩散穿过细胞的细胞质。通过排除法，分泌必定是通过RER与质膜之间的直接连通或通过在RER和质膜之间的细胞质中观察到的小泡进行的。这些数据与高尔基体在糖蛋白生物合成中的普遍性概念不一致。壁层卵黄囊细胞在基底膜生物合成中不使用高尔基体，但在其他蛋白质的生物合成中使用高尔基体。
