Intraspecific chemosignals in the main olfactory system

主嗅觉系统中的种内化学信号

• 批准号: 7856094
• 负责人: WEIHONG LIN
• 金额: $ 24.91万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE COUNTY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-17 至 2012-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7856094
• 关键词: Aging; Animals; Axon; Cessation of life; Chemicals; Clinical Treatment; Code; Cues; Cyclic AMP; Data; Disease; Enzymes; Exhibits; Female; Functional disorder; Genetic; Genetic Status; Image; Ion Channel; Knock-out; Knockout Mice; Knowledge; Maps; Mediating; Methods; Monitor; Mus; Neurons; Olfactory Epithelium; Pathway interactions; Pattern; Perception; Pheromone; Phospholipase C; Physiological; Population; Property; Proteins; Records; Relative (related person); Reproduction; Role; Sensory; Signal Transduction; Social Interaction; System; Testing; Tyrosine 3-Monooxygenase; Urine; computerized data processing; cyclic-nucleotide gated ion channels; falls; novel; olfactory bulb; programs; public health relevance; receptor; research study; response; social; urinary

DESCRIPTION (provided by applicant): Olfactory perception of intraspecific chemosignals provides sensory information about social and sexual status, genetic makeup, and species identity. In this proposal we describe experiments to investigate activities induced by these chemosignals and their underlying transduction mechanisms. Previously we have shown that the main olfactory system employs both cAMP- and phospholipase C- mediated pathways in pheromone signaling. Genetic knockout of the cyclic nucleotide-gated channel subunit 2 (CNGA2), which eliminates the cAMP signaling, does not eliminate pheromone-induced activation. In our preliminary study, we find that a novel signaling component, Transient Receptor Potential channel M5 (TRPM5), is present in a subset of mouse mature OSNs involved in olfactory signaling of pheromones and urinary components. Knockout of both CNGA2 and TRPM5 results in profound aberration in the main olfactory epithelium and bulbs, indicating the functional importance of TRPM5 in olfactory signaling. We hypothesize that TRPM5 is involved in signaling of intraspecific chemical cues in the main olfactory system. The proposed experiments fall into 3 aims. 1) We will test whether functional TRPM5 is crucial for intraspecific signal-evoked glomerular activation patterns. We will examine intraspecific chemosignals-induced activation in olfactory bulbs use immunolabeling of Fos protein as a neuronal activation marker and construct glomerular activation maps using a glomerular mapping program. We will then determine whether activated glomeruli receive input from the TRPM5-expressing OSNs, and whether knockout of TRPM5 alters the activation patterns. 2) We will test whether TRPM5-expressing OSNs provide sensory input to sustain tyrosine hydroxylase activity found in single CNGA2 knockout mice and whether double- knockouts of both CNGA2 and TRPM5 result in abnormality and neuronal death in the main olfactory system using anatomical and immunocytochemical approaches. 3) We will test whether TRPM5 is involved in signal transduction of intraspecific chemosignals in OSNs. We will characterize electrical and Ca2+ responses to pheromones and urine components in OSNs from TRPM5-GFP, TRPM5 knockout-GFP, CNGA2 knockout-TRPM5GFP mice and determine the functions of TRPM5 and associated pathways using Ca2+ imaging and electrophysiological recording methods. Taken together, the proposed studies will provide fundamental knowledge on signaling processing of intraspecific chemical cues and functional roles of TRPM5 in the main olfactory system. PUBLIC HEALTH RELEVANCE: In this application, we propose to investigate olfactory signaling mechanisms and the abnormality resulted from dysfunction of ion channels in the olfactory epithelium. Olfactory deficits are known to associate with aging and diseases. Our studies will provide knowledge ultimately useful for clinical treatment of olfactory dysfunctions.

描述（由申请人提供）：种内化学信号的嗅觉感知提供了有关社会和性地位、遗传组成和物种身份的感官信息。在这个建议中，我们描述了实验，以调查这些化学信号及其潜在的转导机制诱导的活动。以前，我们已经表明，主要的嗅觉系统采用cAMP和磷脂酶C介导的信息素信号转导途径。基因敲除环核苷酸门控通道亚基2（CNGA 2），消除cAMP信号，不消除信息素诱导的激活。在我们的初步研究中，我们发现一种新的信号成分，瞬时受体电位通道M5（TRPM 5），是目前在一个子集的小鼠成熟OSN参与嗅觉信号的信息素和尿液成分。CNGA 2和TRPM 5两者的敲除导致主要嗅上皮和嗅球中的深刻畸变，表明TRPM 5在嗅觉信号传导中的功能重要性。我们推测TRPM 5参与了主要嗅觉系统中种内化学信号的传递。所提出的实验分为3个目标。1)我们将测试功能性TRPM 5是否对种内信号诱发的肾小球激活模式至关重要。我们将研究种内化学信号诱导的激活嗅球使用免疫标记的Fos蛋白作为神经元激活标记物和构建肾小球激活地图使用肾小球映射程序。然后，我们将确定激活的肾小球是否接受来自TRPM 5表达OSN的输入，以及TRPM 5的敲除是否改变了激活模式。2)我们将使用解剖学和免疫细胞化学方法测试表达TRPM 5的OSN是否提供感觉输入以维持在单一CNGA 2敲除小鼠中发现的酪氨酸羟化酶活性，以及CNGA 2和TRPM 5两者的双敲除是否导致主要嗅觉系统中的异常和神经元死亡。3)我们将测试TRPM 5是否参与OSN中种内化学信号的信号转导。我们将表征TRPM 5-GFP、TRPM 5敲除-GFP、CNGA 2敲除-TRPM 5GFP小鼠的OSN中对信息素和尿液组分的电和Ca 2+响应，并使用Ca 2+成像和电生理记录方法确定TRPM 5和相关通路的功能。总之，拟议的研究将提供种内化学线索的信号处理和TRPM 5在主要嗅觉系统中的功能作用的基础知识。 公共卫生相关性：在本研究中，我们拟探讨嗅觉信号转导机制以及嗅觉上皮细胞中离子通道功能障碍所导致的异常。已知嗅觉缺陷与衰老和疾病有关。我们的研究将为嗅觉功能障碍的临床治疗提供最终有用的知识。