Heterotrimeric G-protein regulation of neurotransmission in C. elegans

异源三聚体 G 蛋白对线虫神经传递的调节

基本信息

批准号：
7219194
负责人：
Kevin Michael Collins
金额：
$ 4.48万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-02-01 至 2010-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7219194
关键词：
1,2-diacylglycerol Adult Affect Anabolism Animal Feed Behavior Biochemical Biological Biological Assay Brain Caenorhabditis elegans Cell division Cells Diglycerides Embryo Endocytosis Enzymes Eukaryota Eukaryotic Cell Exocytosis Family member Frequencies G-Protein-Coupled Receptors GTP-Binding Proteins Gene Expression Genes Genetic Genetic Screening Genetic Transcription Guanosine Triphosphate Phosphohydrolases Heterotrimeric GTP-Binding Proteins Human Hydrolysis Imagery In Situ Inositol 1,4,5-Trisphosphate Ion Channel Light Maps Microarray Analysis Microtubules Mitotic Mitotic spindle Molecular Molecular Profiling Muscle Contraction Muscle Tremors Mutation Nematoda Nervous system structure Neurodegenerative Disorders Neurons Parkinson Disease Perception Pharmacologic Substance Phenotype Phosphatidylinositols Phospholipase C Phospholipids Positioning Attribute Protein Biosynthesis Rate Regulation Research Second Messenger Systems Seizures Sensory Serotonin Signal Pathway Signal Transduction Soil Suppressor Mutations Synapses Synaptic Vesicles Syndrome Testing Transducers Tryptophan 5-monooxygenase base cell growth cell motility egg in vivo member mutant neurotransmission novel phosphatidylinositol phosphate receptor research study response second messenger sensor

项目摘要

DESCRIPTION (provided by applicant): Signaling through heterotrimeric GTPases (G-proteins) activates cellular effector enzymes and ion channels to regulate cell growth, mitotic division, and sensory perception. G-protein coupled receptors are among the most commonly used signal transducers in eukaryotes and are the targets of about half of prescribed Pharmaceuticals. The soil nematode, Caenorhabditis elegans, offers many experimental advantages to investigate the conserved features of heterotrimeric G-protein signaling. In embryos, G- proteins regulate microtubule forces that control mitotic spindle positioning during asymmetric cell division. In adults, G-proteins coordinate animal feeding, motility, and other behaviors by altering synaptic activity and the frequency of muscle contractions. These behaviors offer convenient and quantitative assays to study intracellular and intercellular signaling genetically. Through three independent lines of experimentation, I will study the molecular and cellular consequences of signaling through two G-proteins, EGL-30 (Gctq) and GOA-1 (Ga0). Activated EGL-30 interacts with EGL- 8, the phosphatidylinositol (4,5) bisphosphate (PlPz)-specific Phospholipase C (p) family member. Hydrolysis of PIP? by EGL-8 releases the second messengers inositol 1,4,5-triphosphate (IP3) and 1,2- diacylglycerol (DAG). In contrast, direct effectors of activated GOA-1 remain unknown. To find these, I will isolate mutants that suppress hyperactivated GOA-1 signaling phenotypes. One suppressor has already been mapped by members of the Koelle lab, and I will map additional suppressor mutations, determine how the encoded factors regulate signaling, and test whether they act as direct effectors for GOA-1. Second, to study how GOA-1 antagonizes EGL-30 signaling to modulate synaptic activity, I will visualize EGL-8 activity in vivo using established fluorescent sensors of Ca+2 and specific phospholipids. I will test how mutations that impair or stimulate inhibitory GOA-1 signaling affect the behavior and distribution of these indicators. These in situ biochemical experiments will reveal the cell biological consequences of the signaling pathways defined genetically. Finally, to find genes whose expression is regulated by signaling, I will compare gene expression profiles in goa-1 and egl-30 mutants by microarray analysis. This research will shed light on how the nervous system controls the frequency of muscle contractions. As these functions are perturbed during human brain seizures, muscle tremors, and neurodegenerative diseases such as Parkinson's, these studies should inform a rational basis for targeted therapies.

描述（由申请人提供）：通过异三聚体 GTP 酶（G 蛋白）发出的信号激活细胞效应酶和离子通道，以调节细胞生长、有丝分裂和感觉知觉。 G 蛋白偶联受体是真核生物中最常用的信号转导器之一，也是大约一半处方药物的靶标。土壤线虫秀丽隐杆线虫为研究异源三聚体 G 蛋白信号传导的保守特征提供了许多实验优势。在胚胎中，G 蛋白调节微管力，从而控制不对称细胞分裂期间有丝分裂纺锤体的定位。在成人中，G 蛋白通过改变突触活动和肌肉收缩频率来协调动物进食、运动和其他行为。这些行为为研究细胞内和细胞间信号转导提供了方便和定量的方法。通过三个独立的实验，我将研究通过两种 G 蛋白 EGL-30 (Gctq) 和 GOA-1 (Ga0) 信号传导的分子和细胞后果。活化的 EGL-30 与 EGL-8（磷脂酰肌醇 (4,5) 二磷酸 (PlPz) 特异性磷脂酶 C (p) 家族成员）相互作用。 PIP的水解？ EGL-8释放第二信使肌醇1,4,5-三磷酸（IP3）和1,2-二酰基甘油（DAG）。相比之下，激活 GOA-1 的直接效应子仍然未知。为了找到这些，我将分离出抑制过度激活的 GOA-1 信号表型的突变体。 Koelle 实验室的成员已经绘制了一种抑制基因图谱，我将绘制其他抑制基因突变图谱，确定编码因子如何调节信号传导，并测试它们是否充当 GOA-1 的直接效应子。其次，为了研究 GOA-1 如何拮抗 EGL-30 信号传导以调节突触活性，我将使用已建立的 Ca+2 和特定磷脂荧光传感器来可视化体内 EGL-8 活性。我将测试损害或刺激抑制性 GOA-1 信号传导的突变如何影响这些指标的行为和分布。这些原位生化实验将揭示遗传定义的信号通路的细胞生物学后果。最后，为了找到表达受信号传导调节的基因，我将通过微阵列分析比较 goa-1 和 egl-30 突变体的基因表达谱。这项研究将揭示神经系统如何控制肌肉收缩的频率。由于这些功能在人类大脑癫痫发作、肌肉震颤和帕金森氏症等神经退行性疾病期间受到干扰，因此这些研究应该为靶向治疗提供合理的基础。