Deciphering Caenorhabditis elegans molecular nociception using mass spectrometry-based proteomics and network biology

秀丽隐杆线虫（秀丽隐杆线虫）是与哺乳动物生物学相关的功能基因组学的强大动物模型系统，被广泛用于研究伤害性行为。有趣的是，成年秀丽隐杆线虫由959个细胞组成，其中302个是神经元，这使得该模型在生理和分子水平上研究伤害感觉具有吸引力。瞬时受体电位（TRP）通道在伤害性化学刺激和热刺激的加工过程中起着核心作用。在哺乳动物中，TRP通道的激活触发了感觉信息向中枢神经系统的传播，从而导致痛觉。促炎感觉神经肽，如速激肽从这些激活的神经末梢释放，导致神经源性炎症。在脊髓水平，神经肽在疼痛传递和突触化学中起着核心作用。秀丽隐杆线虫基因组编码多个TRP通道，涵盖所有7个TRP亚家族，包括TRPV类似物（如OSM-9和ocr - 1-4）。最近已经确定秀丽隐杆线虫的TRP通道与行为和生理过程有关，包括感觉转导。秀丽隐杆线虫的许多TRP通道与脊椎动物的TRP通道具有相似的激活和调节机制。此外，最近的研究表明，来自MSFamide家族的神经肽（nlp）和fmramide相关肽（FLPs）与哺乳动物神经肽具有功能相似性，但很少被彻底表征。神经肽参与了包括运动、机械和化学感觉在内的所有行为的调节。神经肽作为神经调节剂和快速神经递质。这些神经肽在线虫中的广泛存在表明神经肽能信号在秀丽隐杆线虫中的基本作用，但其机制知识仍然非常有限。拟议研究的目标将是：(1)量化野生型和靶向突变（如OSM-9， OCR1-4）秀丽隐杆线虫与热和化学刺激相关的伤害性行为；(2)采用自下而上的蛋白质组学方法和SILAC归一化的质谱方法对秀丽隐杆线虫进行表征；(3)利用蛋白质组学数据进行全面的生物信息学分析（如独创性途径分析、GeneMANIA），以确定相关的关系、机制、功能、生物网络和途径。我们相信这将为秀丽隐杆线虫伤害行为和化学突触的分子事件提供重要的见解。更好地理解秀丽隐杆线虫的这些机制将改变我们的研究能力，使我们和其他人能够在分子水平上对伤害感觉进行更全面的研究

Caenorhabditis elegans (C.elegans) is a powerful animal model system for functional genomics relevant to mammalian biology and it is extensively used to study nociceptive behavior. Interestingly, adult C.elegans consists of 959 cells, of which 302 are neurons, which make this model attractive to study nociception at the physiological and molecular levels. Transient receptor potential (TRP) channels have a central role in the processing of nociceptive chemical and thermal stimuli. In mammals, the activation of TRP channels triggers the propagation of sensory information back to the central nervous system, which leads to pain sensation. Pro-inflammatory sensory neuropeptides, such as tachykinins are released from these activated nerve endings resulting in neurogenic inflammation. At the spinal level, neuropeptides play a central role in pain transmission and in the synaptic chemistry. The C.elegans genome encodes several TRP channels covering all of the seven TRP subfamilies including TRPV analogs (e.g. OSM-9 and OCR1-4). It has been recently established that C.elegans TRP channels are associated with behavioral and physiological processes, including sensory transduction. Many C.elegans TRP channels share similar activation and regulatory mechanisms with their vertebrate counterparts. Moreover, recent studies revealed that neuropeptides from the MSFamide family (NLPs) and FMRamide-related peptides (FLPs) share functional similarities with mammal neuropeptides but very few have been thoroughly characterized. Neuropeptides are involved in the modulation of essentially all behaviors including locomotion, mechano- and chemosensation. Neuropeptides are acting as neuromodulators and as fast neurotransmitters. The broad existence of these neuropeptides in nematodes suggests a fundamental role of neuropeptidergic signalling in C.elegans but the mechanistic knowledge remains very limited. The objectives of the proposed research will be to (1) Quantify nociceptive behaviors of wild type and targeted mutant (e.g. OSM-9, OCR1-4) C.elegans associated with thermal and chemical stimuli; (2) Characterize C.elegans by mass spectrometry using proteomic bottom-up approaches and SILAC normalization; (3) Generate comprehensive bioinformatics analyses (e.g. Ingenuity Pathway Analysis, GeneMANIA) using the proteomic data to identify relationships, mechanisms, functions, biological networks and pathways of relevance. We believed it will provide significant insight in the molecular events implicated in C.elegans nociceptive behaviors and chemical synapses. A better comprehension of these mechanisms in C.elegans will transform our powers of investigation, allowing us, and others, to pursue more comprehensive study of nociception at the molecular level.**