Regulation of Neurite Outgrowth in N1E-115 Cells through PDZ-Mediated Recruitment of Diacylglycerol Kinase ζ
Regulation of Neurite Outgrowth in N1E-115 Cells through PDZ-Mediated Recruitment of Diacylglycerol Kinase ζ
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通过 PDZ 介导的二酰基甘油激酶募集调节 N1E-115 细胞中的神经突生长
DOI：
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发表时间：
2005
影响因子：
5.3
通讯作者：
S. Gee
中科院分区：
文献类型：
--
作者：
Yury Yakubchyk;H. Abramovici;Jean;Elias Daher;Christopher Obagi;R. Parks;M. Topham;S. Gee
合成营养蛋白是调节二酰基甘油激酶β（DGK-PKD）亚细胞定位的支架蛋白，DGK-PKD是一种磷酸化脂质第二信使二酰基甘油以产生磷脂酸的酶。DGK-β和突触营养蛋白在发育和成年脑的神经元中大量表达，但它们的功能尚不清楚。在这里，我们表明，它们存在于细胞体，神经突，生长锥培养的皮层神经元和分化的N1 E-115神经母细胞瘤细胞。在血清存在的情况下，N1 E-115细胞中DGK-β的过表达诱导神经突形成，这通常阻止神经突生长。这种作用不依赖于DGK-PDZ激酶活性，但依赖于功能性C-末端PDZ结合基序，其特异性地与促突触蛋白PDZ结构域相互作用。具有封闭C末端的DGK-BK 3突变体作为显性负抑制剂，抑制来自血清剥夺的N1 E-115细胞和皮层神经元的生长。有几条证据表明DGK-β通过与GTK Rac 1结合促进神经突生长。DGK-β与Rac 1共定位于神经元突起，DGK-β诱导的生长被显性负性Rac 1抑制。此外，DGK-Rac通过位于其C1结构域内的结合位点直接与Rac 1相互作用。这些蛋白质与促突触蛋白一起在N1 E-115细胞中形成三级复合物。模拟MARCKS结构域磷酸化的DGK-Rac突变体不能结合活化的Rac 1突变体（Rac 1V 12），并且佛波醇肉豆蔻酸酯乙酸酯诱导的蛋白激酶C活化抑制DGK-Rac与Rac 1V 12的相互作用，表明蛋白激酶C介导的MARCKS结构域磷酸化负调节DGK-Rac与活性Rac 1的结合。总的来说，这些发现表明DGK-β，syntrophin和Rac 1形成了一个受调节的信号复合物，控制神经元细胞的极化生长。
ABSTRACT Syntrophins are scaffold proteins that regulate the subcellular localization of diacylglycerol kinase ζ (DGK-ζ), an enzyme that phosphorylates the lipid second-messenger diacylglycerol to yield phosphatidic acid. DGK-ζ and syntrophins are abundantly expressed in neurons of the developing and adult brain, but their function is unclear. Here, we show that they are present in cell bodies, neurites, and growth cones of cultured cortical neurons and differentiated N1E-115 neuroblastoma cells. Overexpression of DGK-ζ in N1E-115 cells induced neurite formation in the presence of serum, which normally prevents neurite outgrowth. This effect was independent of DGK-ζ kinase activity but dependent on a functional C-terminal PDZ-binding motif, which specifically interacts with syntrophin PDZ domains. DGK-ζ mutants with a blocked C terminus acted as dominant-negative inhibitors of outgrowth from serum-deprived N1E-115 cells and cortical neurons. Several lines of evidence suggest DGK-ζ promotes neurite outgrowth through association with the GTPase Rac1. DGK-ζ colocalized with Rac1 in neuronal processes and DGK-ζ-induced outgrowth was inhibited by dominant-negative Rac1. Moreover, DGK-ζ directly interacts with Rac1 through a binding site located within its C1 domains. Together with syntrophin, these proteins form a tertiary complex in N1E-115 cells. A DGK-ζ mutant that mimics phosphorylation of the MARCKS domain was unable to bind an activated Rac1 mutant (Rac1V12) and phorbol myristate acetate-induced protein kinase C activation inhibited the interaction of DGK-ζ with Rac1V12, suggesting protein kinase C-mediated phosphorylation of the MARCKS domain negatively regulates DGK-ζ binding to active Rac1. Collectively, these findings suggest DGK-ζ, syntrophin, and Rac1 form a regulated signaling complex that controls polarized outgrowth in neuronal cells.
DOI：
10.1364/josaa.9.000154
发表时间：
1991-10
期刊：
Journal of the Optical Society of America. A, Optics and image science
影响因子：
--
作者：
S. Gibson;Frederick Lanni
通讯作者：
S. Gibson;Frederick Lanni
影响因子：
2.9
作者：
Gee, SH;Quenneville, S;Chabot, J
通讯作者：
Chabot, J
DOI：
10.1073/pnas.95.5.2509
发表时间：
1998-03-03
影响因子：
11.1
作者：
He, TC;Zhou, SB;Vogelstein, B
通讯作者：
Vogelstein, B