Davis J Q, Bennett V
J Biol Chem. 1984 Nov 10;259(21):13550-9.
Brain ankyrin was purified from pig brain membranes in milligram quantities by a procedure involving affinity chromatography on erythrocyte spectrinagarose. Brain ankyrin included two polypeptides of Mr = 210,000 and 220,000 that were nearly identical by peptide mapping and were monomers in solution. Brain ankyrin and erythrocyte ankyrin are closely related proteins with the following properties in common: 1) shared antigenic sites, 2) high-affinity binding to the spectrin beta subunit at the midregion of spectrin tetramers, 3) a binding site for the cytoplasmic domain of the erythrocyte anion channel, 4) a binding site for tubulin, 5) a similar domain structure with a protease-resistant domain of Mr = 72,000 that contains the spectrin-binding activity and domains of Mr = 95,000 (brain ankyrin) or 90,000 (erythrocyte ankyrin) that contain binding sites for both tubulin and the anion channel. Brain ankyrin is present at about 100 pmol/mg of membrane protein in demyelinated membranes based on radioimmunoassay with antibody raised against brain ankyrin and affinity purified on brain ankyrin-agarose. Brain spectrin tetramers are present at 30 pmol/mg of membrane protein. Brain ankyrin thus is present in sufficient amounts to attach spectrin to membranes. Brain ankyrin also may attach microtubules to membranes independently of spectrin and has the potential to interconnect microtubules and spectrin-associated actin filaments.
通过在红细胞血影蛋白琼脂糖上进行亲和层析的方法，从猪脑膜中纯化出了毫克量的脑锚蛋白。脑锚蛋白包含两种分子量分别为210,000和220,000的多肽，通过肽图谱分析它们几乎完全相同，且在溶液中为单体。脑锚蛋白和红细胞锚蛋白是密切相关的蛋白质，具有以下共同特性：1）共享抗原位点；2）在血影蛋白四聚体的中部区域与血影蛋白β亚基具有高亲和力结合；3）红细胞阴离子通道胞质结构域的结合位点；4）微管蛋白的结合位点；5）相似的结构域结构，具有一个分子量为72,000的抗蛋白酶结构域，该结构域包含血影蛋白结合活性，以及分子量为95,000（脑锚蛋白）或90,000（红细胞锚蛋白）的结构域，这些结构域包含微管蛋白和阴离子通道的结合位点。基于用针对脑锚蛋白产生的抗体进行放射免疫测定，并在脑锚蛋白琼脂糖上进行亲和纯化，在脱髓鞘膜中脑锚蛋白的含量约为100 pmol/mg膜蛋白。脑血影蛋白四聚体的含量为30 pmol/mg膜蛋白。因此，脑锚蛋白的含量足以将血影蛋白附着于膜上。脑锚蛋白也可能独立于血影蛋白将微管附着于膜上，并且有可能使微管与血影蛋白相关的肌动蛋白丝相互连接。
