Gupta R S, Soltys B J
Department of Biochemistry, McMaster University, Hamilton, ON, Canada.
Biochem Mol Biol Int. 1996 May;38(6):1211-21.
The bacterial FtsZ protein has recently been suggested as a probable prokaryotic homolog of the tubulin family of proteins (Cell 80, 1995, 367-370). We have compared the sequence similarity of tubulins to FtsZ and another protein glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Both these proteins exhibited similar levels of sequence identity to the tubulins, which in a few cases was indicated to be significant. We report that incubation of the GAPDH in microtubule assembly buffer causes its polymerization into filamentous structures. In eukaryotic cells, GAPDH is known to be associated with cytoskeletal structures and it binds specifically to both tubulins and colchicine. The latter is a distinctive characteristic of the tubulin family of proteins. These observations indicate that similar to the FtsZ proteins, GAPDH also exhibits a number of intriguing similarities to the tubulins. Whether any of these proteins truly represent the prokaryotic homolog of tubulin, however, is unclear at present.
细菌FtsZ蛋白最近被认为可能是微管蛋白家族蛋白的原核同源物（《细胞》80卷，1995年，367 - 370页）。我们比较了微管蛋白与FtsZ以及另一种蛋白甘油醛 - 3 - 磷酸脱氢酶（GAPDH）的序列相似性。这两种蛋白与微管蛋白的序列一致性水平相似，在少数情况下显示出显著意义。我们报告称，将GAPDH在微管组装缓冲液中孵育会使其聚合成丝状结构。在真核细胞中，已知GAPDH与细胞骨架结构相关，并且它能特异性地结合微管蛋白和秋水仙碱。后者是微管蛋白家族蛋白的一个显著特征。这些观察结果表明，与FtsZ蛋白类似，GAPDH也与微管蛋白表现出许多有趣的相似之处。然而，目前尚不清楚这些蛋白中是否有任何一种真正代表微管蛋白的原核同源物。
