Pathological retrograde signaling in ALS

ALS 中的病理逆行信号传导

基本信息

批准号：
7916362
负责人：
Robert G Kalb
金额：
$ 24.43万
依托单位：
CHILDREN'S HOSP OF PHILADELPHIA
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-09-01 至 2012-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7916362
关键词：
Address Amyotrophic Lateral Sclerosis Axon Binding Biological Biological Models Brain-Derived Neurotrophic Factor Candidate Disease Gene Cell Surface Receptors Cell Survival Cell membrane Cells Clinical Trials Control Groups Dendrites Disease Progression Distal Dose Endocytosis Engineering Event Familial Motor Neuron Disease Forced expiratory volume function Genes Goals Growth In Vitro Individual Lesion Light Location Measures Microarray Analysis Molecular Motor Neuron Disease Motor Neurons Mutate Nature Neurites Neurodegenerative Disorders Neurotrophic Tyrosine Kinase Receptor Type 2 Pathogenesis Patients Predisposition Presynaptic Terminals Process Property Protein Biosynthesis Proteins Receptor Activation Rodent Model Signal Transduction Surface System Testing Toxic effect high risk in vivo insight interest mutant neuronal cell body novel patient assistance public health relevance research study retrograde transport

项目摘要

DESCRIPTION (provided by applicant): The activation of the receptor TrkB by brain derived neurotrophic factor (BDNF) supports the survival of pure motor neurons in vitro and rescues motor neurons in some in vivo lesion paradigms. In addition, growing motor neurons in the presence of BDNF will induce a state of vulnerability to toxic insults. For example, when motor neurons are grown in a cocktail of trophic factors including BDNF, TrkB antagonism (genetically or pharmacologically) protects against excitotoxic and proteotoxic insults relevant to ALS. The mechanism of this adverse property of BDNF-TrkB signaling is incompletely understood but is known to depend on de novo protein synthesis. TrkB is displayed on the plasma membrane of axons, dendrites and the cell soma. Using Campenot compartment culture system, we find that activation of Trk in the axo- dendritic domain (not the cell soma) renders motor neurons vulnerable to toxic insult. Since axons and dendrites differ dramatically at the cell and molecular biological level it is essential to determine from which compartment the vulnerability signal originates. In Specific aim #1, we will generate chimeric TrkB proteins that target its expression to either the axonal or the dendritic domain. Next we will determine in which compartment TrkB activation leads to vulernability mutant SOD toxicity. The repertoire of mRNAs in the axo-dendritic domain is at least partially distinct from those present in the cell body. A microarray analysis provides us with candidate molecules that might underlie the molecular mechanism of the effect of BDNF. In Specific aim #2, we will manipulate the expression strong candidate molecules and determine if they abrogate the capacity of BDNF to render motor neurons vulnerable to insult. These high-risk-high gain experiments will provide novel insight into the pathogenesis of motor neuron disease. PUBLIC HEALTH RELEVANCE: Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease in which motor neurons die and individuals become progressively weak. In rodent model systems, activation of a cell surface receptor called TrkB can make motor neurons vulnerable to insults relevant to ALS. In this proposal we will determine where on the surface of a motor neuron (e.g., axons versus dendrites) activation of TrkB renders them vulnerable to insult. Next we will study the importance of candidate molecules in axons or dendrites that undergo new synthesis upon activation of TrkB. These studies will bring mechanistic insight into why motor neurons die in ALS.

描述（由申请人提供）：脑衍生的神经营养因子（BDNF）激活受体TRKB（BDNF）在某些体内病变范式中支持纯运动神经元的存活，并挽救运动神经元。此外，在BDNF存在下生长的运动神经元将引起对有毒侮辱的脆弱状态。例如，当运动神经元以营养因素的鸡尾酒生长时，包括BDNF，TRKB拮抗作用（遗传学或药理上）可以防止与ALS相关的兴奋性毒性和蛋白质毒性损伤。 BDNF-TRKB信号传导的这种不良特性的机制尚不完全理解，但已知取决于从头蛋白质的合成。 TRKB显示在轴突，树突和细胞体的质膜上。使用Campenot隔室培养系统，我们发现轴突树状结构域（而非细胞体）中TRK的激活使运动神经元容易受到有毒损伤的影响。由于轴突和树突在细胞和分子生物学水平上发生巨大不同，因此必须确定脆弱性信号源于哪个隔室。在特定的目标＃1中，我们将生成嵌合TRKB蛋白，将其表达靶向轴突或树突状结构域。接下来，我们将确定哪种隔室TRKB激活导致脆弱性突变SOD毒性。 Axo树枝状结构域中mRNA的曲目至少部分与细胞体中存在的曲线不同。微阵列分析为我们提供了候选分子，这些分子可能是BDNF作用的分子机制的基础。在特定的目标＃2中，我们将操纵表达强的候选分子，并确定它们是否消除了BDNF使运动神经元容易受到侮辱的能力。这些高风险的增益实验将为运动神经元疾病的发病机理提供新的见解。公共卫生相关性：肌萎缩性侧索硬化症（ALS）是一种神经退行性疾病，运动神经元死亡，个体变得逐渐弱。在啮齿动物模型系统中，称为TRKB的细胞表面受体的激活可以使运动神经元容易受到与ALS相关的侮辱。在此提案中，我们将确定trkb的运动神经元（例如轴突与树突）的表面在哪里，使它们容易受到侮辱的影响。接下来，我们将研究候选分子在激活TRKB后经历新合成的轴突或树突中的重要性。这些研究将使机械性洞察运动神经元为什么在ALS中死亡。