Functional comparisons of the lysophosphatidic acid receptors, LPA1NVZG-1/EDG-2, LPA2/EDG-4, and LPA3/EDG-7 in neuronal cell lines using a retrovirus expression system
Functional comparisons of the lysophosphatidic acid receptors, LPA1NVZG-1/EDG-2, LPA2/EDG-4, and LPA3/EDG-7 in neuronal cell lines using a retrovirus expression system
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DOI：
10.1124/mol.58.5.895
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发表时间：
2000-11-01
影响因子：
3.6
通讯作者：
Chun, J
中科院分区：
文献类型：
--
作者：
Ishii, I;Contos, JJA;Chun, J
溶物磷脂酸（LPA）是一种有效的脂质介质，对各种细胞和组织具有多种生理作用。三个同源G蛋白偶联受体已被鉴定为哺乳动物LPA受体：LPA1/VZG-1/EDG-2，LPA2/EDG-4和LPA3/EDG-7。这些基因的小鼠形式在源自神经系统细胞的啮齿动物细胞系中进行了分析，这些细胞可以在功能上表达这些受体。使用了有效的逆转录病毒表达系统，并在B103大鼠神经母细胞瘤细胞中异源表达，在所有测试的测定中既不表达这些受体也不反应LPA。进行了在配体递送几分钟内激活的信号通路的比较分析。 LPA在LPA1和LPA2表达细胞中诱导细胞舍入。相比之下，LPA3表达导致B103细胞中的神经突伸长，并抑制了TR小鼠神经细胞细胞中LPA依赖性细胞的圆形，内源表达LPA1和LPA2，但未抑制LPA3。每个受体都可以将其与多种G蛋白相结合，并诱导LPA磷酸磷酸肌醇的产生，有丝分裂原激活的蛋白激酶激活和花生四烯酸释放，同时抑制Forskolin诱导的校园积累，尽管LPA的效果和效果从受体到受体变化。这些结果表明三种哺乳动物LPA受体之间的共享和不同功能。本研究中开发的逆转录病毒应提供用于在体内解决这些功能的工具。
Lysophosphatidic acid (LPA) is a potent lipid mediator with diverse physiological actions on a wide variety of cells and tissues. Three cognate G-protein-coupled receptors have been identified as mammalian LPA receptors: LPA1/VZG-1/EDG-2, LPA2/EDG-4, and LPA3/EDG-7. The mouse forms of these genes were analyzed in rodent cell lines derived from nervous system cells that can express these receptors functionally. An efficient retrovirus expression system was used, and each receptor was heterologously expressed in B103 rat neuroblastoma cells that neither express these receptors nor respond to LPA in all assays tested. Comparative analyses of signaling pathways that are activated within minutes of ligand delivery were carried out. LPA induced cell rounding in LPA1- and LPA2 expressing cells. By contrast, LPA3 expression resulted in neurite elongation in B103 cells and inhibited LPA-dependent cell rounding in TR mouse neuroblast cells that endogenously express LPA1 and LPA2 but not LPA3. Each of the receptors could couple to multiple G-proteins and induced LPA-dependent inositol phosphate production, mitogen-activated protein kinase activation, and arachidonic acid release while inhibiting forskolin-induced cAMP accumulation, although the efficacy and potency of LPA varied from receptor to receptor. These results indicate both shared and distinct functions among the three mammalian LPA receptors. The retroviruses developed in this study should provide tools for addressing these functions in vivo.