Mechanisms of virus-induced apoptosis in neurons and CNS

描述(申请人提供)：中枢神经系统(CNS)病毒感染是由于病毒损伤大脑和脊髓内的神经元和其他非神经元细胞的能力造成的。一组不同的嗜神经病毒损伤中枢神经系统中的靶细胞的一个共同机制是通过细胞凋亡。尽管如此，人们对导致病毒诱导的神经细胞凋亡的确切机制和特定的细胞通路知之甚少。在这项建议中，我们将利用原代神经元培养中的呼肠孤病毒感染和呼肠孤病毒诱导的脑炎小鼠模型来研究病毒诱导神经元凋亡所涉及的细胞途径。我们先前已经证明，死亡受体凋亡信号有助于呼肠孤病毒诱导的神经细胞凋亡。我们推测，线粒体和内质网细胞应激、凋亡信号通路在呼肠孤病毒诱导的神经细胞死亡中也起着关键作用。在目标1中，我们将确定内质网(ER)和细胞应激(GADD)通路在呼肠孤病毒诱导的神经细胞凋亡中所起的作用，并对相关因素进行表征。在目标2中，我们将确定线粒体和线粒体因子在呼肠孤病毒诱导的细胞凋亡中的作用。最后，在目标3中，我们将在体内测试调控凋亡通路在呼肠孤病毒诱导的中枢神经系统感染发病机制中的作用。拟议研究的一个关键方面是将体外原代神经元培养研究获得的结果转化为中枢神经系统病毒感染的体内模型的能力。之所以选择呼肠孤病毒感染进行这些研究，是因为它是最广泛描述的病毒诱导的细胞凋亡模型之一，并且提供了关于病毒诱导的凋亡决定因素和所涉及的细胞通路的大量现有知识基础，以及易于在小鼠体内建立的中枢神经系统细胞凋亡模型，该模型允许快速检测在细胞培养中获得的结果在体内中枢神经系统病毒病的发病机制中的意义。

DESCRIPTION (provided by applicant): Central nervous system (CNS) viral infections result from the capacity of viruses to injure neurons and other non-neuronal cells within the brain and spinal cord. A common mechanism by which a diverse group of neurotropic viruses injure target cells in the CNS is through apoptosis. Despite this fact, little is known about the precise mechanisms and specific cellular pathways leading to virus-induced apoptotic neural cell death. In this proposal we will utilize reovirus infection of primary neuronal cultures and a murine model of reovirus- induced encephalitis to examine the cellular pathways involved in virus-induced neuronal apoptosis. We have previously shown that death receptor apoptotic signaling contributes to reovirus-indced neuronal apoptosis. We hypothesize that both mitochondrial and endoplasmic reticulum cell stress apoptotic signaling pathways are also critical to reovirus-induced neuronal cell death. In Aim 1 we will determine the role played by endoplasmic reticulum (ER) and cellular-stress (GADD) pathways on reovirus-induced neuronal apoptosis and characterize the factors involved. In Aim 2 we will determine the role of mitochondria and mitochondrial factors in reovirus-induced apoptosis. Finally, in Aim 3 we will test the effects of manipulating apoptotic pathways on the pathogenesis of reovirus-induced CNS infection in vivo. A key aspect of the proposed studies is the ability to translate results obtained in studies of primary neuronal cultures in vitro, into an in vivo model of CNS viral infection. Reovirus infection was selected for these studies because it is one of the most extensively characterized models of virus-induced apoptosis and offers the advantage of a large pre- existing base of knowledge concerning viral determinants of apoptosis and the cellular pathways involved, as well as an easily accessible in mouse model of CNS apoptosis that allows rapid testing of results obtained in cell culture for their significance on the pathogenesis of CNS viral disease in vivo