Zimmer W E, Zagon I S, Casoria L A, Goodman S R
Department of Structural and Cellular Biology, University of South Alabama College of Medicine, Mobile 36688.
Brain Res. 1992 Jun 5;582(1):94-100. doi: 10.1016/0006-8993(92)90321-y.
A new axonal isoform of amelin, an analogue of the erythrocyte spectrin binding protein termed protein 4.1 has been identified in mouse brain. This new isoform has a molecular weight of 93 kDa, and migrates to a more acidic pH (pH 7.5-8.0) than the previously described amelin E (pH 8.5) on two dimensional NEPHGE-SDS PAGE. The 93 kDa protein looks nearly identical to amelin E on two dimensional chymotryptic iodopeptide mapping, and both share partial homology with rbc protein 4.1. The new isoform is located in axons, and the soma of neurons in mouse cerebellum, while amelin E is located in neuronal soma and dendrites. The axonal amelin antibody detects a 97 kDa protein in embryonic tissue which diminishes during development; and a 93 kDa protein which is first seen at postnatal day 1 of mouse brain ontogeny, increasing constantly to its adult concentrations. This time course of expression is quite different than amelin E, which is present at embryonic day 15 and diminishes constantly reaching its lowest concentration in the adult brain. We hypothesize that axonal amelin and amelin E may play important roles in the interaction of brain spectrin(240/235) and brain spectrin(240/235E) with f-actin and neuronal membranes.
在小鼠大脑中发现了一种新的amelin轴突异构体，它是红细胞血影蛋白结合蛋白（称为蛋白4.1）的类似物。这种新异构体的分子量为93 kDa，在二维非平衡pH梯度-十二烷基硫酸钠聚丙烯酰胺凝胶电泳（NEPHGE-SDS PAGE）上，其迁移至比先前描述的amelin E（pH 8.5）更偏酸性的pH值范围（pH 7.5 - 8.0）。在二维胰凝乳蛋白酶碘肽图谱上，93 kDa的蛋白与amelin E看起来几乎相同，并且两者都与红细胞蛋白4.1有部分同源性。新异构体位于小鼠小脑的轴突以及神经元胞体中，而amelin E位于神经元胞体和树突中。轴突amelin抗体在胚胎组织中检测到一种97 kDa的蛋白，该蛋白在发育过程中减少；还检测到一种93 kDa的蛋白，它在小鼠脑发育的出生后第1天首次出现，并持续增加至成年浓度。这种表达的时间进程与amelin E有很大不同，amelin E在胚胎第15天出现，并持续减少，在成年大脑中达到最低浓度。我们推测轴突amelin和amelin E可能在脑血影蛋白（240/235）和脑血影蛋白（240/235E）与丝状肌动蛋白和神经元膜的相互作用中发挥重要作用。
