Uchida Y, Tomonaga M, Nomura K
J Neurochem. 1986 May;46(5):1376-81. doi: 10.1111/j.1471-4159.1986.tb01750.x.
Age-related changes in amounts of myelin proteins from rat sciatic nerve or spinal root were analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE). In the aged peripheral nerve myelin, the relative amounts of band 105K and proteins X and Y increased, whereas those of proteins P0 and P1 and band 190K decreased. Band 105K purified by preparative SDS-PAGE exhibited three bands of 105K, 28K, and 21K at the second electrophoresis. A repeated SDS-PAGE did not improve the purity of bank 105K, but increased the ratio of 21K to 28K. Compared with P0 protein, band 105K has a very similar peptide map pattern and amino acid composition, as well as the identical NH2 terminal residue, isoleucine. These findings suggest that band 105K is an aggregate form of P0 protein and its fragment, 21K. The 21K protein is a distinct entity from X protein. The quantitative and qualitative alterations in myelin proteins, as we report here, may reflect continuing demyelination and remyelination in aged peripheral nerves.
采用十二烷基硫酸钠（SDS）-聚丙烯酰胺凝胶电泳（PAGE）分析大鼠坐骨神经或脊神经根中髓鞘蛋白含量的年龄相关性变化。在老年周围神经髓鞘中，105K条带以及蛋白X和Y的相对含量增加，而蛋白P0和P1以及190K条带的相对含量减少。通过制备性SDS-PAGE纯化的105K条带在第二次电泳时呈现出105K、28K和21K三条带。重复进行SDS-PAGE并没有提高105K条带的纯度，但增加了21K与28K的比例。与P0蛋白相比，105K条带具有非常相似的肽图模式和氨基酸组成，以及相同的氨基末端残基异亮氨酸。这些发现表明，105K条带是P0蛋白及其片段21K的聚集形式。21K蛋白是一种与X蛋白不同的实体。正如我们在此报道的，髓鞘蛋白的定量和定性改变可能反映了老年周围神经中持续的脱髓鞘和再髓鞘化过程。
