Identification of Synaptic remodeling Genes in C. elegans

描述（由申请人提供）：在神经系统中，突触输入和输出的模式定义了信息流的方向。神经元通过被称为树突的细长过程来检测刺激，并从被称为轴突的形态学上不同的一类细胞质延伸中释放信号。神经元的这些不对称特征是发育控制的，对大脑功能至关重要。在线虫中，C.在elegans中，GABA运动神经元的DD类经历发育调节的突触极性逆转，其中树突转换成轴突并且轴突采用树突的性质。值得注意的是，DD神经元的过程并没有撤回，以适应这种变化，但在原位重塑相互转换前和突触后的专业化。该程序的实施受COUP核激素受体转录因子家族的保守成员EST- 55的调节。因此，我们推测DD运动神经元的极性逆转和突触重塑是转录控制的。我们将使用新的、强大的、细胞特异性的微阵列技术来（1）在发生变态的发育期间对DD运动神经元进行分析，以及（2）利用unc-55突变体来鉴定unc-55调节的转录物。这些数据集的比较，应该揭示强有力的候选基因，编排极性逆转和随之而来的突触重塑的DD运动神经元。脊椎动物神经元不对称性的明显可塑性和指定神经元极性的分子的进化保守性表明，我们在线虫模型系统中的发现将揭示在调节这些事件中具有重要作用的基因。

DESCRIPTION (provided by applicant): In the nervous system, the pattern of synaptic inputs and outputs defines the direction of information flow. A neuron detects stimuli via elongated processes called dendrites and releases signals from a morphologically distinct class of cytoplasmic extensions called axons. These asymmetric features of neurons are developmentally controlled and fundamentally important to brain function. In the nematode, C. elegans, the DD class of GABA motor neurons undergoes a developmentally regulated reversal of synaptic polarity in which a dendrite switches to become an axon and an axon adopts the properties of a dendrite. Remarkably, DD neuronal processes are not withdrawn to accommodate this change but are remodeled in situ to interconvert pre- and post-synaptic specializations. The implementation of this program is regulated by UNC- 55, a conserved member of the COUP family of nuclear hormone receptor transcription factors. Therefore, we hypothesize that polarity reversal and synaptic remodeling of the DD motor neurons are transcriptionally controlled. We will use new, powerful, cell-specific microarray technology to (1) profile DD motor neurons during the developmental period in which metamorphosis occurs and (2) exploit unc-55 mutants to identify UNC-55 regulated transcripts. A comparison of these data sets should reveal strong candidates for genes that orchestrate polarity reversal and the consequent synaptic remodeling of DD motor neurons. The evident plasticity of vertebrate neuronal asymmetry and the evolutionary conservation of molecules that specify neuronal polarity suggest that our discoveries in a nematode model system will reveal genes with fundamental roles in regulating these events.