TARGET CELL ACTIVATION BY TERMINAL COMPLEMENT COMPLEXES

描述(调查人员摘要)：我们的研究目标是了解 补体末端复合体(C5b-7、C5b-8、C5b-9)的生物学作用 炎症和免疫反应。我们和其他人已经证明了真核生物 保护细胞免受溶细胞性C5b-9h的物种特异性限制 C5b-9的组装和通孔消除了膜插入的TCC。暴露于 因此，有限的C5b-9存活了下来，但伴随着细胞表型的变化。 亚溶体C5b-9起着有丝分裂原的作用，这从诱导 原癌基因和DNA合成随着细胞的生长而增加。RAS，RAF-1， TCC激活ERK1通路。这是一种转导途径 向原子核发出信号。我们克隆了一个新的基因RGC-32(对 补体)，由C5b-9激活，参与细胞周期。研资局-32 过表达增加了DNA的合成。RGC-32与cdc2在细胞内的复合体， 增加了C5b-9。在无细胞系统中，cdc2激酶活性是 RGC-32显著增加。在终末分化的细胞中 少突胶质细胞，C5b-9在没有细胞生长的情况下增加细胞存活率，通过 抑制细胞凋亡。我们的初步数据显示支持和支持 抗细胞凋亡的bcl2家族蛋白受C5b-9调控。这些小说 C5b-9的功能可能参与了细胞表型的改变 炎症和免疫反应。提出了两个具体的假设。目标1。 RGC-32通过调节细胞周期参与细胞周期激活 激活剂。为了测试这一点，我们将检测(I)DNA合成和细胞生长 受RGC-32过表达和内源性RGC-32抑制的影响， (Ii)通过使用突变和缺失的基因与cdc2结合和激活 重组RGC-32蛋白，以及(Iii)TCC信号在细胞周期中的作用 RGC-32的活性。目的2.C5b-9通过以下途径提高少突胶质细胞的存活率 抑制线粒体途径的细胞凋亡。这一假说将由 确定C5b-9影响线粒体途径凋亡的步骤，以及 通过研究C5b-9对促凋亡和抗凋亡bcl2的调节 蛋白质家族。

DESCRIPTION (investigator's abstract): Our research goal is to understand the biological role of terminal complement complexes (C5b-7, C5b-8, C5b-9) in inflammation and immune reaction. We and others have shown that eukaryotic cells are protected from the cytolytic C5b-9 h species-specific restriction of C5b-9 assembly and via elimination of membrane-inserted TCC. Cells exposed to limited C5b-9 are therefore survive, but with cell phenotype alteration. Sublytic C5b-9 acts as a mitogen, and this is shown by induction of proto-oncogenes and increased DNA synthesis with cell growth. The Ras, Raf-1, and ERK1 pathway is activated by TCC. and this is one pathway transducing signaling to nucleus. We have cloned a novel gene RGC-32 (Response Gene to Complement), which is activated by C5b-9 and involved in cell cycle. RGC-32 overexpression increased DNA synthesis. RGC-32 complexes with cdc2 in cells, which is increased by C5b-9. In cell-free systems, the cdc2 kinase activity is markedly increased by RGC-32. In terminally differentiated cells such as oligodendrocytes, C5b-9 increases cell survival without cell growth, through inhibition of apoptosis. Our preliminary data indicated both pro- and anti-apoptotic BCL-2 family proteins are regulated by C5b-9. These novel functions of C5b-9 may be involved in cell phenotype alteration during inflammation and immune reactions. Two specific hypotheses are proposed. Aim 1. RGC-32 is involved in cell cycle activation through regulation of cell cycle kinases. To test this, we will examine (i) DNA synthesis and cell growth affected by overexpression of RGC-32 and by inhibition of endogenous RGC-32, (ii) the binding to and activation of cdc2 by using mutated and deleted recombinant RGC-32 proteins, and (iii) the role of TCC signaling on the activity of RGC-32. Aim 2. C5b-9 increases survival of oligodendrocytes by inhibiting mitochondrial pathway apoptosis. This hypothesis will be explored by identifying the steps of mitochondrial pathway apoptosis affected by C5b-9, and by investigating C5b-9-mediated regulation of the pro- and anti-apoptotic BCL-2 family of proteins.