European Molecular Biology Laboratory, Postfach 10.2209, D-6900 Heidelberg, FRG.
EMBO J. 1982;1(1):59-62. doi: 10.1002/j.1460-2075.1982.tb01124.x.
Lysates were made of whole salivary glands from Chironomus tentans and electron microscopic spreads prepared according to Miller and Beatty (1969). The sedimented material consisted mainly of ribosomes, most of which were present in giant polysomes which showed gradients of material protruding laterally from the ribosomes, interpreted as nascent polypeptide chains. Each giant polysome contained one such gradient. On the basis of the presence of a small group of terminal ribosomes without nascent chains at the 3' end, 19 apparently complete polysomes were selected, representing a discrete class of polysomes containing between 66 and 92 ribosomes (79 +/- 7, m +/- s.d.). Arguments are presented that they constitute the translation units for giant secretory proteins coded by RNA from the large Balbiani rings, BR1 and BR2.
从摇蚊的全唾液腺中提取了溶菌产物，并根据 Miller 和 Beatty（1969）的方法制备了电子显微镜铺片。沉淀物质主要由核糖体组成，其中大部分存在于巨型多核糖体中，这些多核糖体显示出物质从核糖体侧向突出的梯度，被解释为新生多肽链。每个巨型多核糖体都包含这样一个梯度。基于在 3' 末端没有新生链的一小群末端核糖体的存在，选择了 19 个显然完整的多核糖体，它们代表了一类含有 66 到 92 个核糖体的离散多核糖体（79 +/- 7，m +/- s.d.）。有论据表明，它们构成了由大巴尔比尼环 RNA 编码的巨型分泌蛋白的翻译单位，BR1 和 BR2。
