Petruzzelli L, Herrera R, Garcia-Arenas R, Rosen O M
J Biol Chem. 1985 Dec 25;260(30):16072-5.
We have previously reported (Petruzzelli, L., Herrera, R., Garcia, R., and Rosen, O. M. (1985) Cancer Cells 3, 115-121) that adult Drosophila melanogaster contain a specific, high-affinity insulin-binding protein. Insulin-dependent protein tyrosine kinase activity has now been identified in Drosophila. Activity first appears at 6-12 h of embryogenesis, increases during the 12-18-h period and falls to low levels in the adult. 125I-insulin was cross-linked specifically and with high affinity to a protein (Mr = 135,000) throughout embryogenesis and in the adult. However, during the 6-12- and 12-18-h periods of embryogenesis when insulin-dependent protein tyrosine kinase activity is expressed, another protein (Mr = 100,000) becomes cross-linked to 125I-insulin. Crosslinking to both proteins was competitively inhibited by the addition of 100 nM insulin. We conclude that the insulin-binding and insulin-dependent protein tyrosine kinase activities of the mammalian insulin receptor are conserved in Drosophila. However, the insulin-dependent protein tyrosine kinase activity of the receptor is detected only during specific times in embryogenesis.
我们之前曾报道过（彼得鲁泽利，L.，埃雷拉，R.，加西亚，R.，以及罗森，O.M.（1985年）《癌细胞》3，115 - 121），成年黑腹果蝇含有一种特定的、高亲和力的胰岛素结合蛋白。现已在果蝇中鉴定出胰岛素依赖性蛋白酪氨酸激酶活性。该活性在胚胎发育6 - 12小时时首次出现，在12 - 18小时期间增加，在成虫中降至低水平。在整个胚胎发育过程以及成虫中，125I - 胰岛素都能特异性且高亲和力地与一种蛋白质（分子量 = 135,000）交联。然而，在胚胎发育的6 - 12小时和12 - 18小时期间，当胰岛素依赖性蛋白酪氨酸激酶活性表达时，另一种蛋白质（分子量 = 100,000）会与125I - 胰岛素交联。加入100 nM胰岛素会竞争性抑制与这两种蛋白质的交联。我们得出结论，哺乳动物胰岛素受体的胰岛素结合和胰岛素依赖性蛋白酪氨酸激酶活性在果蝇中是保守的。然而，该受体的胰岛素依赖性蛋白酪氨酸激酶活性仅在胚胎发育的特定时期被检测到。
