Liu Y C, Storm D R
Department of Pharmacology, University of Washington School of Medicine, Seattle 98195.
Mol Cell Biochem. 1991;104(1-2):29-34.
Cultured embryonic neurons share a number of characteristic morphological and physiological properties with their counterparts in vivo. For example, differentiating hippocampal neurons in culture develop two distinct classes of processes that serve as dendrites and axons. It has also been shown that the microtubule organization and composition in axons differs from those in dendrites, which may contribute to differential transport of macromolecules into axons or dendrites. We have expressed a neuromodulin-beta-galactosidase fusion gene in cultured mesencephalic neurons in order to study the transport of the neurospecific protein neuromodulin into neurite growth cones. When beta-galactosidase alone was expressed in neurons, it was found in the cell bodies with diffuse neurite staining. In marked contrast, the neuromodulin-beta-galactosidase fusion protein was rapidly transported into neurites and was concentrated in the growth cones. This system may provide a useful model for studying the structural domain(s) of neuromodulin that are required for transport and accumulation of neuromodulin in the growth cones of neurons.
培养的胚胎神经元与其在体内的对应物具有许多特征性的形态和生理特性。例如，培养中分化的海马神经元会形成两类不同的突起，分别作为树突和轴突。研究还表明，轴突中的微管组织和组成与树突中的不同，这可能有助于大分子向轴突或树突的差异运输。我们在培养的中脑神经元中表达了神经调节蛋白-β-半乳糖苷酶融合基因，以研究神经特异性蛋白神经调节蛋白向神经突生长锥的运输。当仅在神经元中表达β-半乳糖苷酶时，它存在于细胞体中，神经突呈弥漫性染色。与之形成鲜明对比的是，神经调节蛋白-β-半乳糖苷酶融合蛋白迅速运输到神经突中，并集中在生长锥中。该系统可能为研究神经调节蛋白在神经元生长锥中运输和积累所需的结构域提供一个有用的模型。
