Nishi M, Steiner D F
Department of Biochemistry, Howard Hughes Medical Institute, University of Chicago, Illinois 60637.
Mol Endocrinol. 1990 Aug;4(8):1192-8. doi: 10.1210/mend-4-8-1192.
The degu, Octodon degus, is a South American hystricomorph rodent that is of interest because it develops spontaneous diabetes mellitus and has been found to have islet amyloidosis. To help clarify these problems we have cloned cDNAs encoding islet amyloid polypeptide (IAPP), insulin, and glucagon precursors from this species. The predicted amino acid sequence of degu IAPP is very similar to that of nonamyloid-forming guinea pig IAPP. In contrast, degu insulin and the C-terminal region of degu glucagon are highly divergent from those of other mammals, as is also the case in the guinea pig, suggesting the existence of some form of positive evolutionary pressure on these hormones of carbohydrate metabolism in the hystricomorph rodents.
八齿鼠（Octodon degus）是一种南美洲豪猪型啮齿动物，因其会自发患上糖尿病且已发现存在胰岛淀粉样变而备受关注。为了帮助阐明这些问题，我们从该物种中克隆了编码胰岛淀粉样多肽（IAPP）、胰岛素和胰高血糖素前体的cDNA。八齿鼠IAPP的预测氨基酸序列与不形成淀粉样蛋白的豚鼠IAPP非常相似。相比之下，八齿鼠胰岛素和八齿鼠胰高血糖素的C末端区域与其他哺乳动物的差异很大，豚鼠也是如此，这表明在豪猪型啮齿动物中，碳水化合物代谢的这些激素存在某种形式的正向进化压力。
