团头鲂对两种气味的行为响应、嗅觉电生理及OR表达模式分析

Study of Two Olfactory Stimuli on Electrophysiological Responses, Behavioral Patterns, and Olfactory Receptor Gene Expression in Megalobrama amblycephala

  • 摘要:
    目的 为探究鱼类的嗅觉在社会气味((氯化铵))和警戒气味(团头鲂血液)识别中的作用,
    方法 实验借助嗅电反应和行为学研究了团头鲂对不同气味的敏感度和行为偏好性,并采用实时荧光定量PCR(RT-qPCR)研究了不同气味刺激后10个代表性嗅觉受体基因(ORs)在团头鲂嗅囊(OE)、嗅球(OB)和脑(brain)中的表达差异。
    结果 嗅觉电生理研究结果发现,团头鲂在两种气味刺激后的嗅电反应幅值随刺激浓度增加而增强,呈明显的剂量-效应关系。行为学实验结果表明,团头鲂对氯化铵表现为适应,对血液气味表现为躲避反应。氯化铵和血液刺激诱导ORs基因在团头鲂OE、OB及Br中的表达模式存在显著差异。二者均能诱导OE中Beta-2、Epsilon-10、Delta-58显著上调;氯化铵仅上调OB中Beta-2,血液则特异性上调OB中Beta-9、Beta-10、Epsilon-10、Delta-58;Br中二者均上调Beta-2、Beta-11、Epsilon-13,且氯化铵额外上调Beta-9、Epsilon-10。
    意义 研究构建了鱼类水下嗅电反应与行为学研究装置,分别在电生理和行为学水平证实了团头鲂对社会气味和警戒气味的敏感性和差异性行为,结果为后续深入探究鱼类的嗅觉识别机制奠定了基础。

     

    Abstract: Social odor and alarm odor are key chemical signals for fish to perceive the environment and regulate behavior. The olfactory system underlies the sensitivity and behavioral response differences of fish to different odors, a process that initiates with the specific recognition and signal transduction of olfactory receptors. The molecular and behavioral mechanisms of this process are one of the core contents for analyzing chemical communication in fish. To explore the recognition patterns of the fish olfactory system towards such cues, we assessed the sensitivity and behavioral preference of the M. amblycephala to these odorants were assessed using electro-olfactogram recordings and behavioral assays. Furthermore, quantitative real-time PCR (RT-qPCR) was employed to compare the expression levels of 10 representative olfactory receptors (ORs) in the olfactory epithelial, olfactory bulb and brain. EOG results demonstrated that EOG amplitudes increased exponentially in response to both odorants across concentrations, indicating a clear dose-response relationship. Behavioral tests have shown that M. amblycephala exhibits adaptive responses to ammonium chloride (without significant attraction or avoidance) and displays avoidance behavior towards conspecific blood. Following ammonium chloride stimulation, the expression levels of Beta-2, Epsilon-10 and Delta-58 was significantly up-regulated in the olfactory epithelium. Beta-2 was significantly up-regulated in the olfactory bulb, and Beta-2, Beta-9, Beta-11, Epsilon-10 and Epsilon-13 was significantly up-regulated in the brain (P<0.05). Following blood stimulation, the expression of Beta-2, Epsilon-10 and Delta-58 was significantly up-regulated in the olfactory epithelial, while Beta-9, Beta-10, Epsilon-10 and Delta-58 were significantly up-regulated in the olfactory bulb, and Beta-2, Beta-11 and Epsilon-13 were significantly up-regulated in the brain (P<0.05). This study developed an integrated underwater system for recording olfactory-electrophysiological responses and behavioral behaviors in fish. At both electrophysiological and behavioral levels, M. amblycephala was demonstrated sensitivity to social odorants and alarm stimuli and exhibited significant avoidance responses. These findings provide a foundational basis for further investigation into the mechanisms of olfactory recognition in fish.

     

/

返回文章
返回