微管相关蛋白2的可变剪接变体MAP2a。

MAP2a, an alternatively spliced variant of microtubule-associated protein 2.

作者信息

Chung W J, Kindler S, Seidenbecher C, Garner C C

机构信息

Neurobiology Research Center, University of Alabama at Birmingham 35213-0021, USA.

出版信息

J Neurochem. 1996 Mar;66(3):1273-81. doi: 10.1046/j.1471-4159.1996.66031273.x.

DOI:10.1046/j.1471-4159.1996.66031273.x

Abstract

MAP2, a dendritically localized microtubule-associated protein (MAP), consists of a pair of high molecular mass (280 kDa) polypeptides, MAP2a and MAP2b, and several low molecular mass (70 kDa) proteins called MAP2c. Although MAP2b and MAP2c have been shown to arise via alternative splicing. It was not clear whether MAP2a is also created by alternative splicing or by posttranslational modification. Using epitope peptide mapping, we have demonstrated that an element specific to MAP2a is situated at its N-terminal end. A cDNA clone from an adult rat brain library was found to contain an additional 246 nucleotides situated at the 5' end of the 9-kb MAP2 mRNA. Antibodies generated against the encoded protein sequence recognize specifically MAP2a in rat brain homogenates. Moreover, although MAP2a, like MAP2b, is found in dendrites and cell bodies, its temporal appearance and cell type-specific distribution in rat brain differs from MAP2b.

摘要

微管相关蛋白2（MAP2）是一种定位于树突的微管相关蛋白，由一对高分子量（280 kDa）的多肽MAP2a和MAP2b以及几种低分子量（70 kDa）的蛋白（称为MAP2c）组成。尽管已表明MAP2b和MAP2c是通过可变剪接产生的。但尚不清楚MAP2a是通过可变剪接还是通过翻译后修饰产生的。利用表位肽图谱分析，我们已经证明MAP2a特有的一个元件位于其N末端。从成年大鼠脑文库中获得的一个cDNA克隆被发现包含位于9 kb MAP2 mRNA 5'端的另外246个核苷酸。针对编码蛋白序列产生的抗体在大鼠脑匀浆中特异性识别MAP2a。此外，尽管MAP2a与MAP2b一样存在于树突和细胞体中，但其在大鼠脑中的出现时间和细胞类型特异性分布与MAP2b不同。