Wang J, Tolan D R, Pagliaro L
Center for Bioengineering, University of Washington, Seattle 98195, USA.
Exp Cell Res. 1997 Dec 15;237(2):445-51. doi: 10.1006/excr.1997.3811.
The glycolytic enzyme aldolase is concentrated in a domain around stress fibers in living Swiss 3T3 cells, but the mechanism by which aldolase is localized has not been revealed. We have recently identified a molecular binding site for F-actin on aldolase, and we hypothesized that this specific binding interaction, rather than a nonspecific mechanism, is responsible for localizing aldolase in vivo. In this report, we have used fluorescent analog cytochemistry of a site-directed mutant of aldolase to demonstrate that actin-binding activity localizes this molecule along stress fibers in quiescent cells and behind active ruffles in the leading edge of motile cells. The specific cytoskeletal association of aldolase could play a structural role in cytoplasm, and it may contribute to metabolic regulation, metabolic compartmentation, and/or cell motility. Functional duality may be a widespread feature among cytosolic enzymes.
糖酵解酶醛缩酶在活的瑞士3T3细胞中集中于应力纤维周围的区域，但醛缩酶的定位机制尚未揭示。我们最近在醛缩酶上鉴定出一个F-肌动蛋白的分子结合位点，并且我们推测这种特异性结合相互作用而非非特异性机制负责醛缩酶在体内的定位。在本报告中，我们使用醛缩酶定点突变体的荧光类似物细胞化学来证明肌动蛋白结合活性使该分子沿着静止细胞中的应力纤维以及运动细胞前缘的活跃褶皱后方定位。醛缩酶与细胞骨架的特异性结合可能在细胞质中起结构作用，并且它可能有助于代谢调节、代谢区室化和/或细胞运动。功能双重性可能是胞质酶中的一个普遍特征。
