Le Roith D, Shiloach J, Roth J, Lesniak M A
Proc Natl Acad Sci U S A. 1980 Oct;77(10):6184-8. doi: 10.1073/pnas.77.10.6184.
Tetrahymena pyriformis, Neurospora crassa, and Aspergillus fumigatus that had been grown in simple defined media were extracted with acid ethanol by a classic method for recovering insulin from pancreas. After filtration of the extracts on Sephadex G-50, distinct peaks of insulin immunoreactivity were recovered in the region typical of insulin. The gel-filtered material from the Tetrahymena had reactivity in the pork insulin radioimmunoassay about equal to its reactivity in the insulin bioassay (stimulation of lipogenesis in isolated rat adipocytes), and the gel-filtered material from neurospora had an immunoreactivity-to-bioactivity ratio of about 1:3. The material that stimulated lipogenesis could be neturalized by anti-insulin sera (i.e., 75-95% of the Tetrahymena material and 60% of the Neurospora material). Bioactive and immunoactive insulin was found in the conditioned medium equal in amount to that in the cells. The findings suggest that insulin did not arise evolutionarily in the intestinal or neural tissues of primitive vertebrates or complex invertebrates but rather has its molecular origins at least as far back as the simplest unicellular eukaryotes.
采用从胰腺中提取胰岛素的经典方法，用酸性乙醇对在简单限定培养基中培养的梨形四膜虫、粗糙脉孢菌和烟曲霉进行提取。提取物经葡聚糖凝胶G - 50过滤后，在胰岛素的典型区域回收了明显的胰岛素免疫反应峰。来自四膜虫的凝胶过滤物质在猪胰岛素放射免疫测定中的反应性与其在胰岛素生物测定（刺激分离的大鼠脂肪细胞中的脂肪生成）中的反应性大致相等，来自脉孢菌的凝胶过滤物质的免疫反应性与生物活性之比约为1:3。刺激脂肪生成的物质可被抗胰岛素血清中和（即四膜虫物质的75 - 95%和脉孢菌物质的60%）。在条件培养基中发现的生物活性和免疫活性胰岛素的量与细胞中的量相等。这些发现表明，胰岛素并非在原始脊椎动物或复杂无脊椎动物的肠道或神经组织中进化产生，而是其分子起源至少可追溯到最简单的单细胞真核生物。
